Search

Abstract Largemouth bass (Micropterus salmoides, LMB) is an important aquaculture species due to its excellent flesh quality and environmental adaptability. It has been continuously introduced to many countries and cultured for decades. Here, an LMB population was used for selective breeding to improve growth rate and feed adaptability. After five generations of breeding, the growth rate improved by 38%, and feed adaptability improved by 22% compared to the non-breeding population. To study the underlying genetic mechanism, 100 LMB from the breeding population and 100 from the non-breeding population were sampled for whole-genome resequencing. The population genetics analysis shows that the breeding population has a higher inbreeding coefficient and linkage disequilibrium (LD) level, a lower nucleic acid diversity and effective population size (Ne). Using $$F_{ST}$$ (fixation index), we found that the average $$F_{ST}$$ value between the two populations was 0.07, with the highest $$F_{ST}$$ value reaching 0.38, which overlaps with the trypsin gene. Additionally, other genes exhibiting high $$F_{ST}$$ values are associated with functions such as neural development, glucose metabolism, and growth. Using $$F_{ST}$$ and nucleic acid diversity as criteria, we identified 698 genes that are positively selected in the breeding population, and gene functional enrichment analysis shows that 36 genes are related to the olfactory receptor pathway. Overall, our study found that multiple genes were selected in the LMB breeding population. These genes may be associated with adaptation and digestion of artificial feed in fish.

Color vision, which is mediated by cone photoreceptors in vertebrates, is essential for perceiving the external environment. Bisphenol A (BPA) and its substitute bisphenol S (BPS) have been widely used worldwide, while the evaluation of their safety, especially the newly discovered visual toxicity mechanism caused by them in recent years, has not been clearly explored. In the present study, we investigated the effects of BPA treatment (1, 10, and 100 μg/L) on cone cell development and function to evaluate visual toxicity. We also compared the mechanisms of color deficiency induced by BPA and BPS at the same concentrations. The results indicated that BPA (10 and 100 μg/L) caused the abnormal proliferation (increased number of cone cells), morphological abnormalities (increased height of cone cells), mosaic pattern disorder, and depressed expression of key genes related to the photo-transduction pathway, and impaired the light perception ability of both red and UV cones ultimately. Similar to the BPA exposure group, BPS (1, 10, and 100 μg/L) exposure resulted in structural damage and mosaic arrays disorder of red and UV cone photoreceptors. In contrast to BPA exposure, BPS exposure resulted in significant activation of key genes involved in the phototransduction pathway. Our data indicate that both BPS and BPA exposure can interfere with the development of cone cells, and two types of compounds disturb the transduction of photon signals within cone cells in different ways, which further impaired the retinal spectral sensitivity to the light signal. This study clarifies the root cause for color vision impairment induced by BPA from the perspective of cone-mediated color vision. It also clarified that the BPA and its substitute BPS may not be entirely safe at the single-cell level.

Understanding the diversity and function of fish gut microbiomes has advanced substantially, yet many aspects remain poorly understood, particularly the interplay among microbiota, host species, and environmental factors in the context of conservation. This review explores the composition and abundance of gut bacterial communities in key aquaculture fish groups—cyprinids, ictalurids (catfish), salmonids, and cichlids (tilapia)—alongside the model organism zebrafish, across diverse geographic regions. The findings highlight environmental habitats and host species as primary determinants of gut microbiome structure, offering a global perspective on these microbial communities. Across all fish groups, the phyla Firmicutes, Fusobacteria, and Proteobacteria consistently dominated, while temperate, sub-equatorial, and sub-tropical regions exhibited the highest microbiome diversity, underscoring the contribution of taxonomic and environmental factors. The gut bacterial diversity of farm-raised fish shows a significant divergence from that of wild-caught fish, reflecting the impacts of ecological and management differences. Understanding the dynamic responses of fish gut microbiota is vital for guiding conservation efforts, safeguarding aquatic biodiversity, and advancing sustainable aquaculture practices. Future research should leverage innovative techniques and integrative approaches, both experimental and theoretical, to uncover the functional roles of microbiomes and predict their responses to environmental changes. Expanding geographic and taxonomic coverage will be critical for creating a comprehensive framework to inform global aquaculture and conservation strategies. Collectively, this perspective highlights the transformative potential of microbiome research in addressing global challenges in aquaculture and conservation biology.

Polo-like kinase 1 (PLK1), a key regulator of the G2/M phase in mitosis, is frequently overexpressed in numerous tumors. Although PLK1 inhibitors have emerged as promising therapeutic agents for cancer, their use has been linked to significant anemia in a subset of patients, yet the underlying mechanisms remain poorly understood. In this study, we utilized an in vitro human umbilical cord blood-derived CD34+ cell-based erythroid differentiation system, alongside a murine model, to investigate the impact of PLK1 inhibitors on erythropoiesis. Our results indicate that PLK1 inhibitors, specifically GSK461364 and BI6727, significantly suppress the proliferation of erythroid cells, resulting in G2/M phase cell cycle arrest, increased apoptosis in erythroid cells, and the formation of abnormally nucleated late-stage erythroblasts. In vivo, administration of PLK1 inhibitors in mice induced severe anemia, as evidenced by a marked reduction in red blood cells and hemoglobin levels. More specifically, PLK1 inhibition impaired the differentiation and erythroid commitment of hematopoietic stem cells in the bone marrow, resulting in abnormal accumulation of BFU-E cells and reduced proliferation and differentiation of CFU-E, and a decrease in the number of terminal erythrocytes. Mechanistically, PLK1 inhibitors primarily induce apoptosis in erythroid cells by reducing Mitochondrial membrane potential and arresting the cell cycle at the G2/M phase. Overall, our findings underscore the critical role of PLK1 in erythropoiesis and shed light on the mechanisms underlying PLK1 inhibitor-induced anemia, providing essential guidance for developing strategies to prevent and manage anemia in clinical applications of PLK1-targeted therapies.

Developing innovative sonoreactors to enhance acoustic processing efficiency holds immense importance in the field of sonochemistry. Traditional immersed sonoreactors (TISs) mainly produce cavitation at the probe tip, with a relatively weak cavitation around the probe, resulting in posing challenges for high-efficiency cavitation treatment. Here we propose an acoustic black hole immersed sonoreactor (ABHIS) in longitudinal-flexural coupled vibration, enabling high-efficiency cavitation treatment by unleashing the cavitation potential of the probe. The symmetrical structure of the probe is altered to introduce a coupling of flexural vibration mode, and an acoustic black hole (ABH) profile is integrated to further enhance both flexural wave number and amplitude. In this paper, we present a systematic theoretical design method for ABHIS and compare its performance with TIS using finite element method (FEM). An ABHIS prototype is fabricated and subjected to experimental tests and cavitation observation. The results demonstrate that our theoretical analysis model accurately predicts the frequency characteristics of ABHIS. The proposed ABHIS exhibits satisfactory dynamic characteristics, with significantly increased vibration displacement and acoustic radiation ability compared to TIS. Importantly, the ABH design significantly expands ultrasonic cavitation regions and enhances acoustic radiation intensity of ABHIS, resulting in a substantial improvement in acoustic processing efficiency.

Geographically separated populations of Culter alburnus in China exhibit marked physiological and behavioral characteristics, particularly between populations inhabiting the northern and southern part of Huai River (HR), indicating their adaptation to local environments. In this study, the morphological characteristics of C. alburnus were measured, and restriction site associated DNA (RAD) sequencing was used for C. alburnus to investigate the genomic features of the Xingkai Lake (XKL) population from the northern part and HR, Yangtze River (YR), and Dianshan Lake (DSL) populations from the southern part of China. Analyses results revealed significant morphological differences and population genetic structure among these populations, with pronounced genetic differentiation between the northern and the southern part. Notably, the northern (XKL) population exhibited significantly lower genetic diversity than the other three southern populations. Furthermore, genes involved in synaptic vesicle transmission regulation, androgen receptor signaling, and behavior regulation pathways, including oligophrenin 1, ch25h13, androgen receptor, and Rho kinase genes, showed selection signals with high genetic differentiation indices (Fst), significant nucleotide diversity (Pi) differences, and significantly differential expression values in the northern (XKL) population compared with southern populations. These findings indicate that these genes may influence the different adaptive reflex behavioral responses of northern and southern C. alburnus populations. This study highlights the genetic structure and adaptations of C. alburnus, providing important resources for its management and aquaculture.

Abstract Background Neither a TYRP1-mediated highly conserved genetic network underlying skin color towards optimum defense nor the pathological tendency of its mutation is well understood. The Oujiang Color Common Carp (Cyprinus carpio var. color) as a model organism, offering valuable insights into genetics, coloration, aquaculture practices, and environmental health. Here, we performed a comparative skin transcriptome analysis on TYRP1 mutant and wild fishes by applying a conservative categorical approach considering different color phenotypes. Results Our results reveal that an unusual color phenotype may be sensitized with TYRP1 mutation as a result of upregulating several genes related to an anti-inflammatory autoimmune system in response to the COMT-mediated catecholamine neurotransmitters in the skin. Particularly, catecholamines-derived red/brown, red with blue colored membrane attack complex, and brown/grey colored reduced eumelanin are expected to be aggregated in the regenerated cells. Conclusions It is, thus, concluded that the regenerated cells with catecholamines, membrane attack complex, and eumelanin altogether may contribute to the formation of the unusual (coffee-like) color phenotype in TYRP1 mutant.

The black patches in Oujiang color common carp (Cyprinus carpio var. color) encompasses both the formation of patches and their intricate color distribution, and has been considered as the qualitative trait. Using the crossing families of the two kinds of body color patterns in this carp, ''RB'' (red with big black patches) and ''WW'' (white body), we found Mendel's laws of inheritance patterns of black patches in Oujiang color common carp, suggesting the black patches would be controlled by single dominant gene and looked as a qualitative trait. The coverage ratio of the black patches (CRB) in the hybrid was found continuous and nearly normal distribution. Compared with the parent RB, the sizes of melanocytes were significantly smaller, but the number of melanocytes was significantly higher in the hybrid. The melanin layer under the epidermis (Ep) in the hybrid was nearly one-half of that in the parent RB. The melanin content and tyrosinase activity, melanin metabolic enzyme activity of the skin in the hybrid were in the middle between the parents RB and WW. Furthermore, the six relative gene expression levels of the melanogenesis pathway, Ednrb, Tyr, Tyrp1, Mc1r, Kit and Asip, in the skin of the hybrid were between the parent RB and WW. These results demonstrated that the black patches exhibits quantitative traits in nature. Gene editing on Ednrb by using the CRISPR/Cas9 system showed that the mutants displayed a significantly reduced number of black patches in comparison to the wild-type RB, accompanied by noticeably smaller melanocytes. Generally, our study uncovers the dual nature of the black patches: the presence of black patches is categorized as a qualitative trait, whereas the number of black patches is classified as a quantitative trait.

ObjectiveCognitive impairment represents a notable feature of depressive disorders. Comprehending its characteristics and influencing factors is vital for patient rehabilitation.MethodsThis study is based on the 2015 Shandong Province epidemiological survey of mental disorders, from which 871 individuals meeting DSM-IV criteria for depressive disorders were selected as the research group. Using 1:1:1 matching by sex, age, and residence, we randomly selected 825 individuals with no DSM-IV diagnosis but positive on GHQ-12 and additional risk assessments as the elevated risk control group, and 825 with negative screenings as the minimal risk control group. In 2020, a follow-up survey was conducted, resulting in a final analysis of 1,855 cases. The survey included demographic data, various clinical information, and a series of screening and questionnaire assessments.ResultsThe current depressive group scored lower on the MoCA than the non-depressive group (t=8.86, P

The ROCO family is a family of GTPases characterized by a central ROC-COR tandem domain. Interest in the structure and function of ROCO proteins has increased with the identification of their important roles in human disease. Nevertheless, the functions of most ROCO proteins are still unknown. In the present study, we characterized the structure, evolution, and expression of ROCOs in four species of brown algae. Brown algae have a larger number of ROCO proteins than other organisms reported to date. Phylogenetic analyses showed that ROCOs have an ancient origin, likely originated in prokaryotes. ROCOs in brown algae clustered into four groups and showed no strong relationship with red algae or green algae. Brown algal ROCOs retain the ancestral LRR-ROC-COR domain arrangement, which is found in prokaryotes, plants and some basal metazoans. Remarkably, individual LRR motifs in ROCO genes are each encoded by separate exons and exhibit intense exon shuffling and diversifying selection. Furthermore, the tandem LRR exons exhibit alternative splicing to generate multiple transcripts. Both exon shuffling and alternative splicing of LRR repeats may be important mechanisms for generating diverse ligand-binding specificities as immune receptors. Besides their potential immune role, expression analysis shows that many ROCO genes are responsive to other stress conditions, suggesting they could participate in multiple signal pathways, not limited to the immune response. Our results substantially enhance our understanding of the structure and function of this mysterious gene family.

Gentiana szechenyii Kanitz. and Gentiana veitchiorum Hemsl. are two wild medicinal plants widely used in Tibetan medicine. In recent decades, their wild populations have declined rapidly due to persistent over-harvesting of their flowers. Because their flowers are small and dense, it is difficult to rely on manual counting under wild conditions. The combination of deep learning and unmanned aerial vehicle remote sensing (UAVRS) is a new method for plant surveys. We trained 12 of the most advanced or widely used YOLO models on a custom dataset to achieve quantitative detection of both plant flowers in UAVRS images. The accuracy, precision and recall of G. szechenyii Flower (GSF) detection can reach 97.00%, 90.40% and 95.40%, respectively (based on YOLOv7). Similarly, those of G. veitchiorum Flower (GVF) detection can reach 93.40%, 91.30% and 90.60%, respectively (based on YOLOv5n), and the highest mAP can reach 94.90% (based on YOLOv5m). Based on the detection results, it is calculated that the total yield of dried GSF and GVF that can be harvested as medicinal materials in study area ranges from 1.88 to 2.10 g·m−2 and 4.42–4.62 g·m−2, respectively. The results show that deep learning and UAVRS can be used for quantitative detection of GSF and GVF, which is helpful for further research and protection of these two plants.

Tetracycline has received a great deal of interest for the harmful effects of substance abuse on ecosystems and humanity. The effects of different processes on the degradation of tetracycline were compared, with dual-frequency ultrasound (DFUS) in combination with peroxymonosulfate (PMS) being the most effective for the tetracycline degradation. Free radical scavenging experiments showed that O2∙-, SO4∙- and •OH were the main reactive radicals in the degradation of tetracycline. According to the major intermediates of tetracycline degradation identified, three possible degradation pathways were proposed, which are of significance for translational studies of tetracycline degradation. Notably, these intermediates were found to be significantly less toxicity. The number of active bubbles in the degradation vessel was calculated using a semi-empirical formula, and a higher value of 1.44 × 108 L-1s−1 of bubbles was obtained when using dual-frequency ultrasound at 20 kHz (210 W/L) and 80 kHz (85.4 W/L). Therefore, compared to 20 kHz, although the yield of strong oxidizing substances from individual active bubbles decreased slightly, a significant increment of the number of active bubbles still resulted in a higher synergistic effect, and the combination of DFUS and PMS should be effective in promoting the generation of reactive free radicals and mass transfer processes within the degradation vessel, which provides a method for efficient removal of tetracycline from wastewater.

Abstract As research progresses, the intricate metabolic connections between depression and tryptophan, as well as kynurenine (KYN), have become increasingly evident. In studies investigating the relationship between KYN and depression, the conclusions reached thus far have been inconsistent. Therefore, we propose employing a two-sample mendelian randomization (MR) approach to further elucidate the relationship between KYN and depression. We utilized extensive data from large-scale genome-wide association studies to identify single nucleotide polymorphisms that act as instrumental variables for kynurenine and depression in European ancestry populations, ensuring compliance with MR assumptions. We employed five MR algorithms, namely, weighted median, MR-Egger, inverse variance weighted (IVW), simple mode, and weighted mode, with IVW as the primary analysis method. Sensitivity tests were conducted using Cochran’s Q test, MR-Egger intercept test, MR Pleiotropy Residual Sum and Outlier, and Leave-one-out analysis.The IVW analysis revealed that each standard deviation increase in kynurenine corresponded to a 1.4-fold increase in the risk of depression (OR = 1.351, 95% CI 1.110–1.645, P = 0.003). The direction of the effect size (positive or negative) was consistent with the findings from the other four algorithms. Sensitivity tests indicated no heterogeneity or horizontal pleiotropy among the instrumental variables. Elevated levels of kynurenine have a causal relationship with an increased risk of developing depression.

The cssR gene (ncgl1578) of Corynebacterium glutamicum encodes a repressor of the TetR (tetracycline regulator) family. Its role in the stress response to antibiotics/heavy metals has been investigated, but how CssR functions in response to phenolic compounds in C. glutamicum has been rarely studied. In this study, we applied transcriptomic analysis, β-galactosidase analysis, qRT-PCR, and EMSAs to analyze the target genes and functions of CssR in response to phenolic compounds. Consistent with the upregulation of genes involved in the degradation of phenolic compounds, the ΔcssR mutant was more resistant to various phenolic compounds than was the wild-type strain. Furthermore, the addition of phenolic compounds induced the expression of corresponding genes (ncgl0283, ncgl1032, ncgl1111, ncgl2920, ncgl2923, and ncgl2952) in vivo. However, the DNA binding activity of CssR to the promoter of phenolic compound-degrading genes was undetected in vitro. Additionally, we also found that CssR indirectly negatively regulates the expression of cell wall/membrane/envelope biogenesis-related genes, which may enhance resistance to stress caused by phenolic compounds. Together, our findings demonstrate that CssR is a key regulator that copes with stress conditions induced by phenolic compounds, thus greatly expanding our understanding of the functions of TetR family transcription factors.

Abstract Background The identification and enumeration of medicinal plants at high elevations is an important part of accurate yield calculations. However, the current assessment of medicinal plant reserves continues to rely on field sampling surveys, which are cumbersome and time-consuming. Recently, unmanned aerial vehicle (UAV) remote sensing and deep learning (DL) have provided ultrahigh-resolution imagery and high-accuracy object recognition techniques, respectively, providing an excellent opportunity to improve the current manual surveying of plants. However, accurate segmentation of individual plants from drone images remains a significant challenge due to the large variation in size, geometry, and distribution of medicinal plants. Results In this study, we proposed a new pipeline for wild medicinal plant detection and yield assessment based on UAV and DL that was specifically designed for detecting wild medicinal plants in an orthomosaic. We used a drone to collect panoramic images of Lamioplomis rotata Kudo (LR) in high-altitude areas. Then, we annotated and cropped these images into equally sized sub-images and used a DL model Mask R-CNN for object detection and segmentation of LR. Finally, on the basis of the segmentation results, we accurately counted the number and yield of LRs. The results showed that the Mask R-CNN model based on the ResNet-101 backbone network was superior to ResNet-50 in all evaluation indicators. The average identification precision of LR by Mask R-CNN based on the ResNet-101 backbone network was 89.34%, while that of ResNet-50 was 88.32%. The cross-validation results showed that the average accuracy of ResNet-101 was 78.73%, while that of ResNet-50 was 71.25%. According to the orthomosaic, the average number and yield of LR in the two sample sites were 19,376 plants and 57.93 kg and 19,129 plants and 73.5 kg respectively. Conclusions The combination of DL and UAV remote sensing reveals significant promise in medicinal plant detection, counting, and yield prediction, which will benefit the monitoring of their populations for conservation assessment and management, among other applications.

The complexity and fragmentation of people's activity space are challenging to planners. However, the relevant studies are mostly concerned on the relationship between the social attributes and the activity space of residents in a single or several communities, or the spatiotemporal laws of activity space on a macro scale. The research on the spatial characteristics of residents' activity space still needs to be strengthened. The present study analyses the spatial patterns of residents' activity space based on mobile phone signaling data to fill the gap of previous studies that assessed residents' activity space across small geographic areas. First, according to the spatial scope and direction of an activity space and residents' activity coverage rate, spatial patterns can be divided into three types: compact, extended, and directional extension patterns. The CatBoost method is then used to statistically analyze the influencing variables of spatial patterns, and the order of importance of the following influencing factors is determined: the built environment is more influential than social and economic situations. This study aims to strengthen the understanding of residents' activity space at the spatial level and provide a basis for the optimization of communities with different spatial patterns.

PurposeMolting is a pivotal biological process regulated by the ecdysteroid signaling pathway that requires molecular coordination of two transcription factors, Ecdysone receptor (EcR) and ultraspiracle (USP) in arthropods. However, the molecular interplay of EcR and Retinoid X receptor (RXR), the crustacean homolog of USP in the ecdysteroid signaling pathway, is not well understood.MethodsIn this study, we conducted temporal and spatial expression, co-immunoprecipitation (CO-IP), and luciferase reporter assay experiments to investigate the molecular function and interplay of EcR and RXR during the molting process of the Chinese mitten crab, Eriocheir sinensis.ResultsThe results showed that the expression level of RXR was more stable and significantly higher than EcR during the entire molting process. However, the expression level of EcR fluctuated dynamically and increased sharply at the premolt stage. The CO-IP and luciferase reporter assay results confirmed the molecular interplay of EcR and RXR. The heterodimer complex formed by the two transcription factors significantly induced the transcription of E75, an essential gene in the ecdysteroid signaling pathway.ConclusionsOur study unveiled the diverse molecular function and molecular interplay of EcR and RXR; RXR is possibly a “constitutive-type” gene, and EcR is possibly a vital speed-limiting gene while both EcR and RXR are required to initiate the ecdysteroid signaling cascade, which may be indispensable for molting regulation in E. sinensis. The results provide a theoretical basis for the endocrine control of molting in E. sinensis and novel insights into the molecular mechanism of molting mediated by the ecdysteroid signaling pathway in crustaceans.

We studied the layer structure of bubbles just below water/air and water/EPE (Expand aple poly ephylene) interfaces using high-speed photography. The layer structure was generated by floating spherical clusters, the source bubbles of which were identified to come from the attachment of bubble nuclei at the interface, the floating of bubbles in the bulk liquid, or bubbles generated on the surface of the ultrasonic transducer. The boundary shape affected the layer structure, which assumed a similar profile below the water/EPE interface. We developed a simplified model composed of a bubble column and bubble chain to describe interface impacts and the interaction of bubbles in a typical branching structure. We found that the resonant frequency of the bubbles is smaller than that of an isolated single bubble. Moreover, the primary acoustic field plays an important role in the generation of the structure. A higher acoustic frequency and pressure were found to shorten the distance between the structure and the interface. A hat-like layer structure of bubbles was more likely to exist in the low-frequency (28 and 40 kHz) intense inertial cavitation field, in which bubbles oscillate violently. By contrast, structures composed of discrete spherical clusters were more likely to form in the relatively weak cavitation field at 80 kHz, in which stable and inertial cavitation coexisted. The theoretical predictions were in good agreement with the experimental observations.

Gene duplication plays an important role in the regulation of biological traits. The Tyr inactivation have been confirmed to hinder melanin synthesis, but the research of duplicated Tyr function and evolution in fish, especially in ornamental farm fish, is insufficient. To test whether the duplicated Tyr has effect on black patches formation in Oujiang color common carp (Cyprinus carpio var. color), we obtained duplicated Tyr gene (Tyr1 and Tyr2), each of them possesses biased expression in melanocyte-rich skin, indicating existence of function. The various mutants by disrupting Tyr in white-black (WB) types of Oujiang color common carp using the CRISPR/Cas9 tool were generated. The Tyr2 mosaic mutant WB exhibited shallow black patches, while simultaneously disrupting two Tyr genes caused different levels of melanin loss in the eyes and on black patches. Most obviously, the complete albino individuals were obtained with non-wild type sequence and distinguished from whole white (WW) in the pigmentation of eyes. The correlation analysis between the gene mutation type and phenotype revealed that duplicated Tyr were co-involved in melanogenesis, where Tyr1 was the key factor, and Tyr2 might have been playing compensatory roles on the melanin synthesis in Oujiang color common carp. Our study provided insight into regulation mechanism of black patches formation in fish and breeding of special traits in future.

Introduction: The Abunabu antimony mining area is located between the Indus–Yarlung Tsangpo suture and the southern Tibetan detachment system. Ore deposits in the mining area provide an excellent opportunity to understand the nature and genesis of antimony mineralisation in the Tethys Himalayan metallogenic belt.Methods: In this study, we analysed the He–Ar and S isotopic compositions of stibnite-hosted fluid inclusions as a basis for investigating the sources of ore-forming fluids in the Abunabu mining area and the Tethys Himalayan metallogenic belt.Results: The analysed stibnites have 4He contents of 0.016 × 10−7–1.584 × 10–7 cm3 STP/g, 40Ar contents of 1.37 × 10−7–2.94 × 10–7 cm3 STP/g, 40Ar/36Ar ratios of 303.8–320.7, and 3He/4He (Ra) ratios of 0.021–0.351. These isotopic features indicate that the ore-forming fluids were primarily metamorphic fluids of crustal origin, with small amounts of magmatic-derived materials and modified air-saturated water with low 40Ar*/4He ratios. The δ34S values of stibnite vary within a narrow range of −4.9‰ to −3.5‰, with a mean value of −4.31‰, indicating a deep magmatic origin.Discussion: On the basis of these results and a compilation of data for sulphide deposits in the metallogenic belt, we infer that compositional variations in the He and Ar isotopes of the ore-forming fluids of each antimony deposit in the Tethys Himalayan metallogenic belt are independent of each other. This suggests that antimony deposits in the belt had similar ore-forming fluid sources and mixing processes and that differences in the metallogenic tectonic setting within the belt emerged only in the later stages of deposit evolution. Our new results and compiled data also show that antimony–gold deposits and lead–zinc–antimony polymetallic deposits in the Tethys Himalayan metallogenic belt differ in their sulphur isotopic compositions and that multiple sulphur sources were involved in each of these types of deposit.

Median fins are thought to be ancestors of paired fins which in turn give rise to limbs in tetrapods. However, the developmental mechanisms of median fins remain largely unknown. Nonsense mutation of the T-box transcription factor eomesa in zebrafish results in a phenotype without dorsal fin. Compared to zebrafish, the common carp undergo an additional round of whole genome duplication, acquiring an extra copy of protein-coding genes. To verify the function of eomesa genes in common carp, we established a biallelic gene editing technology in this tetraploidy fish through simultaneous disruption of two homologous genes, eomesa1 and eomesa2. We targeted four sites located upstream or within the sequences encoding the T-box domain. Sanger sequencing data indicated the average knockout efficiency was around 40% at T1-T3 sites and 10% at T4 site in embryos at 24 hours post fertilization. The individual editing efficiency was high to about 80% at T1-T3 sites and low to 13.3% at T4 site in larvae at 7 days post fertilization. Among 145 mosaic F0 examined at four months old, three individuals (Mutant 1–3) showed varying degrees of maldevelopment in the dorsal fin and loss of anal fin. Genotyping showed the genomes of all three mutants were disrupted at T3 sites. The null mutation rates on the eomesa1 and eomesa2 loci were 0% and 60% in Mutant 1, 66.7% and 100% in Mutant 2, and 90% and 77.8% in Mutant 3, respectively. In conclusion, we demonstrated a role of eomesa in the formation and development of median fins in Oujiang color common carp and established an method that simultaneously disrupt two homologous genes with one gRNA, which would be useful in genome editing in other polyploidy fishes.

Acetylation and tri-methylation of histone H3 lysine 9 (H3K9ac and H3K9me3) play an interactive regulatory role in the epigenetic regulation of gene expression during heart development and cardiovascular disease, but little is known about their possible role in heart regeneration. Here we utilized genome-wide high-throughput RNA sequencing (RNA-seq) and chromatin immunoprecipitation with high-throughput sequencing (ChIP-seq) for H3K9ac and H3K9me3, carried out on regenerative cardiac tissues at different days post amputation in zebrafish (Danio rerio) to investigate dynamic changes in gene expression and the epigenetic landscape of H3K9ac and H3K9me3. The STAR, Bowtie2, MACS2, and deepTools2 were mainly used for RNA-Seq or ChIP-seq data analysis. In this article, we present detailed information on experiment design, data generation, quality assessment and processing pipeline. Raw reads of the RNA-seq and ChIP-seq data have been deposited at the NCBI GEO repository with the accession number GSE158104. Our data will be a valuable resource for the elucidation of H3K9ac and H3K9me3 involvement in the regulation of gene transcription during cardiac regeneration.

The mechanism of color pattern formation in animals is complicated. Oujiang color common carp (Cyprinus carpio var. color) is an excellent fish model for studying the molecular mechanism of pigmentation. Solute carrier family 24 member 5 (SLC24A5) was identified as a key gene in regulating melanophore development and melanin distribution in organisms. In this study, functional experiments were conducted on the SLC24A5 gene in Oujiang color common carp. The full-length of SLC24A5 mRNA was cloned and obtained. In Oujiang color common carp, qRT-PCR and whole-mount in situ hybridization indicated that SLC24A5 was highly expressed in tissues in the presence of melanin and initiated its expression along with the presence of melanin during embryo development. The SLC24A5 knocked-out via CRISPR/cas9 caused an obvious loss of melanophore in larva and adult zebrafish. In addition, the homozygous SLC24A5−/− zebrafish mutant phenotype was rescued by the over expression of the SLC24A5 from Oujiang color common carp. Results suggested that SLC24A5 is essential for regulating melanophore development and that the functional and structures of SLC24A5 are conserved in Cyprinidae fish.

The diagnosis of primary aldosteronism (PA) is critical for determining treatment strategies. The aim of the present study was to investigate the clinical value of preoperative adrenal venous sampling (AVS) for determining the benefit of PA surgery. Patients diagnosed with PA at Liaocheng People's Hospital (Liaocheng, China) between January 2015 and December 2020 were selected and divided into two groups: Group A underwent adrenal computed tomography (CT) only, whereas Group B underwent adrenal CT and successful AVS. Subsequently, the improvement rate of adrenal CT and adrenal CT + AVS in the treatment of PA was compared. A total of 164 patients were included, with an average age of 46.69±13.64 years. There were 62 patients in Group A and 102 in Group B. Among the patients diagnosed with unilateral lesions on adrenal CT scan, 82.61% of patients in group A and 87.72% in group B showed improvement; however, the difference was not significant (X² =0.534, P=0.465). Among the patients diagnosed with bilateral lesions on adrenal CT images, 62.50% of patients in Group A and 91.11% of patients in Group B showed improvement (P=0.019). In conclusion, unilateral adrenal lesions detected by CT did not benefit significantly from surgical decision-making after AVS. AVS should be advised for all patients with bilateral adrenal PA who are willing to undergo adrenal surgery, which is conducive to correct lateral segmentation and improve treatment choices. [ABSTRACT FROM AUTHOR]

Abstract Gut microbiomes play an essential role in host survival and local adaptation and thus can facilitate the invasion of host species. Biological invasions have been shown to be linked to the genetic properties of alien host species. It is thus plausible that the holobiont, the host, and its associated microbiome act as an entity to drive invasion success. The bighead carp and silver carp (bigheaded carps), invasive species that exhibit extensive hybridization in the Mississippi River Basin (MRB), provided a unique model to test the holobiont hypothesis of invasion. Here, we investigated the microbiomes of foreguts and hindguts in bigheaded carps and their reciprocal hybrids reared in aquaculture ponds using 16S amplicons and the associated gene prediction. We found an admixed pattern in the gut microbiome community in bigheaded carp hybrids. The hybrid gut microbiomes showed special characteristics such as relatively high alpha diversity in the foregut, an increasing dissimilarity between foreguts and hindguts, and a remarkable proportion of genes coding for putative enzymes related to their digestion of main food resources (Cyanobacteria, cellulose, and chitin). The pond‐reared hybrids had advantageous features in genes coding for putative enzymes related to their diet. The above results collectively suggested that the gut microbiomes of hybrids could be beneficial to their local adaptation (e.g., food resource utilization), which might have facilitated their invasion in the MRB. The gut microbial findings, along with the intrinsic genomic features likely associated with life‐history traits revealed in our recent study, provide preliminary evidence supporting the holobiont hypothesis of invasion.

Molting is a common and periodic process in crustaceans, which make crustacean withdraw from intricate and old exoskeleton, and get an increased body weight after molting. However, the underlying molecular mechanism of internal impetus and physiological features of molting process which impact muscle growth and development is unclear. In this study, the osmotic pressure of hemolymph, histological section, moisture of walking leg muscle, and comparative transcriptome were conducted in Eriocheir sinensis among different molting stages. Osmotic pressure and moisture analysis revealed that a hypertonic environment arose at pre-molt stage, which may induce the initiation of water uptake. The explosive water uptake mainly took place at post-molt stage leading to dramatic weight gain. Comparative transcriptome analysis revealed a total of 2264 differentially expressed genes between pre-molt and post-molt, including 1387 up-regulated genes at pre-molt stage, which negatively regulate muscle growth and development (eg. POMT, NEB2, ZCI2A, and MSTN), and 877 up-regulated genes at post-molt stage which are associated with positive regulation in muscle growth and proliferation (eg. TITIN, mTOR, XRCC, and ICCR). GO enrichment analysis further illustrated that many genes act on proteolysis, ion transport, and transmembrane transport which help with the maintenance of a hypertonic environment in the hemolymph at pre-molt stage. Meanwhile, differentially expressed genes at post-molt stage were enriched in DNA repair and DNA replication indicating the activated muscle growth and development process. Our results provided novel insights into the genetic interplay of osmoregulation, water uptake, and muscle development in E. sinensis during molting.

Self-assembled mesoporous BiOI microsphere with nanosheets were prepared by a solvothermal method and used as sonocatalysts. The sonocatalytic performances of the BiOI microspheres were evaluated in terms of the degradation rate of tetracycline hydrochloride (TCH) as a model pollutant. We designed three comparative experiments to explore the degradation of TCH solution under natural light, namely with sonication, with BiOI alone, and with ultrasound (US)/BiOI synergy. The degradation rate of TCH with US/BiOI synergy was 227 times higher than that achieved with sonication and 83 times higher than that achieved with BiOI alone. The maximum TCH degradation rate was 93.0%. The synergistic effect was therefore significant, and the synergy factor was estimated to be 61. Many factors such as the ultrasonic duty cycle, applied power, catalyst concentration, and initial TCH dye concentration may affect the ultrasonic degradation efficiency. Box–Behnken design of the response surface method were used to optimize the parameters and to study the effects of the catalyst concentration, ultrasonic duty cycle, and applied power. Analysis of variance confirmed that the quadratic response surface model for predicting the sonocatalytic efficiency was good for the corresponding parameters (R2 = 0.9936 and adjusted R2 = 0.9854). The optimization results were verified by replicate experiments. The high TCH degradation rate may be related to the generation of reactive oxygen species at the end of cavitation bubble collapse, which can improve the chemical yields.

The evolution of acoustic Lichtenberg figure (ALF) in ultrasound fields is studied using high-speed photography. It is observed that bubbles travel along the branch to the aggregation region of an ALF, promoting the possibility of large bubble or small cluster formation. Large bubbles move away from the aggregation region while surrounding bubbles are attracted into this structure, and a bubble transportation cycle arises in the cavitation field. A simplified model consisting of a spherical cluster and a chain of bubbles is developed to explain this phenomenon. The interaction of the two units is analyzed using a modified expression for the secondary Bjerknes force in this system. The model reveals that clusters can attract bubbles on the chain within a distance of 2 mm, leading to a bubble transportation process from the chain to the bubble cluster. Many factors can affect this process, including the acoustic pressure, frequency, bubble density, and separation distance. The larger the bubble in the cluster, the broader the attraction region. Therefore, the presence of large bubbles might enhance the process in this system. Local disturbances in bubble density could destroy the ALF structure. The predictions of the model are in good agreement with the experimental phenomena.

Abstract Background Cinnamyl alcohol dehydrogenase (CAD) is an important enzyme functions at the last step in lignin monomer synthesis pathway. Our previous work found that drought induced the expressions of CmCAD genes and promoted lignin biosynthesis in melon stems. Results Here we studied the effects of abscisic acid (ABA), hydrogen peroxide (H2O2) and jasmonic acid (JA) to CmCADs under drought stress. Results discovered that drought-induced ABA, H2O2 and MeJA were prevented efficiently from increasing in melon stems pretreated with fluridone (Flu, ABA inhibitor), imidazole (Imi, H2O2 scavenger) and ibuprofen (Ibu, JA inhibitor). ABA and H2O2 are involved in the positive regulations to CmCAD1, 2, 3, and 5, and JA is involved in the positive regulations to CmCAD2, 3, and 5. According to the expression profiles of lignin biosynthesis genes, ABA, H2O2 and MeJA all showed positive regulations to CmPAL2-like, CmPOD1-like, CmPOD2-like and CmLAC4-like. In addition, positive regulations were also observed with ABA to CmPAL1-like, CmC4H and CmCOMT, with H2O2 to CmPAL1-like, CmC4H, CmCCR and CmLAC17-like, and with JA to CmCCR, CmCOMT, CmLAC11-like and CmLAC17-like. As expected, the signal molecules positively regulated CAD activity and lignin biosynthesis under drought stress. Promoter::GUS assays not only further confirmed the regulations of the signal molecules to CmCAD1~3, but also revealed the important role of CmCAD3 in lignin synthesis due to the strongest staining of CmCAD3 promoter::GUS. Conclusions CmCADs but CmCAD4 are positively regulated by ABA, H2O2 and JA under drought stress and participate in lignin synthesis.

Abstract Purpose Asthma has been shown to be related to an increased risk of invasive pneumococcal disease (IPD), although the results remain inconclusive. Therefore, we performed a meta-analysis to determine whether asthma increases the risk of IPD. This meta-analysis was performed to validate and strengthen the association between asthma and IPD. Methods PubMed, EMBASE, Web of Science, and the reference lists of all relevant articles and books were screened until May 2019. Two authors independently assessed eligibility and study quality and extracted data. A common odds ratio was estimated using a random-effects meta-analysis model of aggregated published data. Results A total of eight studies with 8877 IPD cases and 78,366 controls were included. Our meta-analysis showed that asthma was significantly associated with the increased risk of IPD (OR 2.44 [95% CI, 2.02–2.96]). The children with asthma (0–17 years old) (OR 2.86 [95% CI 1.80–4.55]) had a higher risk of IPD susceptibility compared with the adult patients (≥ 18 years old) (OR 2.45 [95% CI 1.98–3.03]). Conclusions Results of this meta-analysis indicated that the patients with asthma had a higher risk of IPD susceptibility, especially among the children with asthma.

Abstract Bighead carp (Hypophthalmichthys nobilis) and silver carp (H. molitrix), collectively called bigheaded carps, are cyprinids native mainly to China and have been introduced to over 70 countries. Paleontological and molecular phylogenetic analyses demonstrate bighead and silver carps originated from the Yangtze‐Huanghe River basins and modern populations may have derived from the secondary contact of geographically isolated fish during the last glacial events. Significant genetic differences are found among populations of native rivers (Yangtze, Pearl, and Amur) as well as introduced/invasive environments (Mississippi R., USA and Danube R., Hungary), suggesting genetic backgrounds and ecological selection may play a role in population differentiation. Population divergence of bighead carp or silver carp has occurred within their native rivers, whereas, within the Mississippi River Basin (MRB)—an introduced region, such genetic differentiation is likely taking place at least in silver carp. Interspecific hybridization between silver and bighead carps is rare within their native regions; however, extensive hybridization is observed in the MRB, which could be contributed by a shift to a more homogenous environment that lacks reproductive isolation barriers for the restriction of gene flow between species. The wild populations of native bighead and silver carps have experienced dramatic declines; in contrast, the introduced bigheaded carps overpopulate the MRB and are considered two invasive species, which strongly suggests fishing capacity (overfishing and underfishing) be a decisive factor for fishery resource exploitation and management. This review provides not only a global perspective of evolutionary history and population divergence of bigheaded carps but also a forum that calls for international research collaborations to deal with critical issues related to native population conservation and invasive species control.

ObjectiveTo study the mechanism of the effect of Wen-Shen-Jian-Pi (WSJP) prescription on an ALS model comprising mice knocked out for an encoding RNA editing, mice (AR2).MethodsTwenty-four transgenic AR2 mice were randomly divided into a vehicle group, a low dose WSJP group (15 mg), a medium-dose WSJP group (30 mg), and a high-dose WSJP group (45 mg) (all n = 6 per group). In the treatment groups, the WSJP prescription was given once a day while the vehicle group was fed the same volume of water. The weekly changes in body weight, rotarod test, and grip strength were used to detect the changes in the AR2 and changes of the number of normal mitochondria, abnormal mitochondria, and autophagosomes in injured spinal cord cells were used to evaluate the pathogenetic effects of WSJP treatment.ResultsThe WSJP-treated AR2 mice gained weight more quickly from 8 weeks, and showed active behavior and displayed significantly better constant rotarod scores and grip strengths during the experiment compared with those of the vehicle AR2 mice. The number of normal mitochondria in the WSJP-treated AR2 mice had significantly more normal mitochondria than the vehicle group, while the numbers of abnormal mitochondria and autophagosomes were greatly decreased compared with those in the vehicle group.ConclusionThe WSJP prescription could delay the decline in motor function of ALS model mice by reducing the degeneration of neurons. The potential of WSJP to treat ALS should be assessed in a clinical trial.

According to classical nucleation theory, a gas nucleus can grow into a cavitation bubble when the ambient pressure is negative. Here, the growth process of a gas nucleus in a micro-cavity was simplified to two “events”, and the full confinement effect of the surrounding medium of the cavity was considered by including the bulk modulus in the equation of state. The Rayleigh–Plesset-like equation of the cavitation bubble in the cavity was derived to model the radial oscillation and translational motion of the cavitation bubble in the local acoustic field. The numerical results show that the nucleation time of the cavitation bubble is sensitive to the initial position of the gas nucleus. The cavity size affects the duration of the radial oscillation of the cavitation bubble, where the duration is shorter for smaller cavities. The equilibrium radius of a cavitation bubble grown from a gas nucleus increases with increasing size of the cavity. There are two possible types of translational motion: reciprocal motion around the center of the cavity and motion toward the cavity wall. The growth process of gas nuclei into cavitation bubbles is also dependent on the compressibility of the surrounding medium and the magnitude of the negative pressure. Therefore, gas nuclei in a liquid cavity can be excited by acoustic waves to form cavitation bubbles, and the translational motion of the cavitation bubbles can be easily observed owing to the confining influence of the medium outside the cavity.

In this study, the U.S. Environmental Protection Agency prioritized polycyclic aromatic hydrocarbons (PAHs), associated pollution level, and health risks were assessed in a typical coal spontaneous combustion zone in the Rujigou coal mine in Northwestern China. This study used gas chromatography-mass spectrometry (GC-MS) to detect the chemical composition, spatial variation, distribution profiles, impact of coal spontaneous combustion, and health risks of PAHs. The entire study area is divided into three zones according to different features: the spontaneous combustion zone (C-zone), the living zone (L-zone), and the non-spontaneous combustion zone (N-zone). The results showed that: (1) the highest concentrations were measured in the C-zone, and the average concentrations of PAHs in the C-zone, N-zone, and L-zone were 13.28 ng·m−3, 9.56 ng·m−3, and 7.67 ng·m−3, respectively. (2) The PAHs of the study area were mainly composed of three ring to five ring PAHs. (3) EPA positive matrix factorization (PMF) analysis of qualitative source apportionment of PAHs showed that chemical production was the major source of atmospheric PAHs in all three zones, followed by coal combustion. (4) The inhalation of PAHs showed higher potential cancer risk for children than for adults, and the impact of coal combustion in the C-zone was much greater than the other zone. The adverse health impacts associated with PAH exposure indicates the need for mitigation measures of pollution control in this region.

Epoxy resins (EPs) require the addition of flame retardants to extend their application scope. High-efficiency flame retardants typically contain halogens, which can cause tremendous harm to humans and the environment. In this study, we investigated the syntheses of new phosphorus–nitrogen flame retardants (DIT) and flame-retardant EP. DIT is composed of 6-(2,5-dihydroxyphenyl) dibenzo[c,e][1,2] oxaphosphinine 6-oxide, 5-isocyanato-1-(isocyanatomethyl)−1,3,3-trimethylcyclohexane, and tris-(2-hydroxyethyl) isocyanurate. DIT chemical structure was analysed by Fourier-transform infrared spectroscopy. Several formulations of modified epoxy resins (DIT-EPs) were obtained by adding different quantities of DITs. We found that when the flame retardant content reached 25%, the limiting oxygen index of the DIT-EP was 29.0%. This finding expands the application range of EPs.

Abstract The genetic paradox of biological invasions is complex and multifaceted. In particular, the relative role of disparate propagule sources and genetic adaptation through postintroduction hybridization has remained largely unexplored. To add resolution to this paradox, we investigate the genetic architecture responsible for the invasion of two invasive Asian carp species, bighead carp (Hypophthalmichthys nobilis) and silver carp (H. molitrix) (bigheaded carps) that experience extensive hybridization in the Mississippi River Basin (MRB). We sequenced the genomes of bighead and silver carps (~1.08G bp and ~1.15G bp, respectively) and their hybrids collected from the MRB. We found moderate‐to‐high heterozygosity in bighead (0.0021) and silver (0.0036) carps, detected significantly higher dN/dS ratios of single‐copy orthologous genes in bigheaded carps versus 10 other species of fish, and identified genes in both species potentially associated with environmental adaptation and other invasion‐related traits. Additionally, we observed a high genomic similarity (96.3% in all syntenic blocks) between bighead and silver carps and over 90% embryonic viability in their experimentally induced hybrids. Our results suggest intrinsic genomic features of bigheaded carps, likely associated with life history traits that presumably evolved within their native ranges, might have facilitated their initial establishment of invasion, whereas ex-situ interspecific hybridization between the carps might have promoted their range expansion. This study reveals an alternative mechanism that could resolve one of the genetic paradoxes in biological invasions and provides invaluable genomic resources for applied research involving bigheaded carps.

Ctenopharyngodon idellus and Leuciscus idus are two closely related Leuciscinae fish with dramatically different physiologies, especially in terms of immunological performance. However, the intrinsic metabolic difference between these two species has not been fully discovered. In this study, the immunological indexes, such as lysozyme, superoxide dismutase, and alkaline phosphatase activities, and plasma metabolomic profiles of the two species were compared. Our study revealed significant differences in immunological indexes and metabolomic profiles between them. In C. idellus, highly abundant metabolites were enriched in galactose metabolism, pyruvate metabolism, choline metabolism, and ether lipid metabolism. By contrary, in L. idus, highly abundant metabolites were enriched in taurine and hypotaurine metabolism, glycine, serine and threonine metabolism, and glycerophospholipid metabolism. We also identified that the abundances of key immune-performance-related metabolites, such as taurine, betaine, glutathione, gluten exorphin, and fistuloside A were higher in L. idus than in C. idellus. This result indicated that the two species presented distinct immunological performance at metabolomic level. Our study provided a snapshot of the metabolic difference between C. idellus and L. idus, and the key metabolites identified here could be utilized as immunological biomarkers for the aquaculture and selective breeding of C. idellus in the future.

In animals, growth and development are strongly correlated with the gut microbiota and metabolic profiles. In this study, gut microbiome communities, metabolic profiles, and growth performance of Eriocheir sinensis under three dietary feed types based on waterweed plants only, freshwater snails only, and waterweed plants combined with freshwater snails were studied by using 16S rRNA gene sequencing and liquid chromatography-mass spectrometry. Results indicated that different feed types dramatically affected the growth performances of E. sinensis by altering the gut microbiota and metabolic profiles. Aquatic plants, such as waterweeds, played essential roles in shaping gut microbiome communities, and the optimal Bacteroides-to-Firmicutes ratio might strongly promote growth performance. Waterweed plants also helped decrease maleficent Proteobacteria caused by excess animal-type feedstuff, such as freshwater snails, and might have positive roles in antibacterial functions in gut. A diet based on waterweeds only resulted in lipid metabolism disorders, which significantly retarded the growth of E. sinensis. In summary, E. sinensis cultured with a diet of waterweeds and freshwater snails showed superior growth performance due to their healthy gut microbiota and metabolic homeostasis. Our findings unveiled the roles of aquatic plants and animal-type food such as freshwater snail in shaping the gut microbiota and metabolic processes and provided guidance for the aquaculture of E. sinensis in future.

Activin receptor IIB (ActRIIB) is a serine/threonine-kinase receptor binding with transforming growth factor-β (TGF-β) superfamily ligands to participate in the regulation of muscle mass in vertebrates. However, its structure and function in crustaceans remain unknown. In this study, the ActRIIB gene in Eriocheir sinensis (Es-ActRIIB) was cloned and obtained with a 1,683 bp open reading frame, which contains the characteristic domains of TGF-β type II receptor superfamily, encoding 560 amino acids. The mRNA expression of Es-ActRIIB was the highest in hepatopancreas and the lowest in muscle at each molting stage. After injection of Es-ActRIIB double-stranded RNA during one molting cycle, the RNA interference (RNAi) group showed higher weight gain rate, higher specific growth rate, and lower hepatopancreas index compared with the control group. Meanwhile, the RNAi group displayed a significantly increased content of hydrolytic amino acid in both hepatopancreas and muscle. The RNAi group also displayed slightly higher contents of saturated fatty acid and monounsaturated fatty acid but significantly decreased levels of polyunsaturated fatty acid compared with the control group. After RNAi on Es-ActRIIB, the mRNA expressions of five ActRIIB signaling pathway genes showed that ActRI and forkhead box O (FoxO) were downregulated in hepatopancreas and muscle, but no significant expression differences were found in small mother against decapentaplegic (SMAD) 3, SMAD4 and mammalian target of rapamycin. The mRNA expression s of three lipid metabolism-related genes (carnitine palmitoyltransferase 1β (CPT1β), fatty acid synthase, and fatty acid elongation) were significantly downregulated in both hepatopancreas and muscle with the exception of CPT1β in muscles. These results indicate that ActRIIB is a functionally conservative negative regulator in growth mass, and protein and lipid metabolism could be affected by inhibiting ActRIIB signaling in crustacean.

Myostatin (MSTN) is a negative regulation factor involved in skeletal muscle growth and development in vertebrates. In order to understand the multi-functional roles of MSTN in crustaceans, we assessed the molting / growth characters, analyzed the tissues composition and investigated the expression levels of lipid metabolism and immune related genes in Chinese mitten crab (Eriocheir sinensis) after injection of Es-MSTN dsRNA during one molt cycle of 49 days. We found the RNAi group displayed shorter molting interval, higher specific growth rate, and lower hepatosomatic index compared with the control group, evidencing MSTN may also be a negative regulator of muscle growth and development in E. sinensis. In the RNAi group, the expression levels were upregulated for lipid metabolism-related genes of pancreatic lipase (LP), carnitine palmitoyl transferases 1β (CPT1β) and fatty acid-binding protein 3 (FABP3) in muscles, but were downregulated for these three genes and fatty acid-binding protein 9 (FABP9) in hepatopancreas. Meanwhile, the expression levels were all upregulated for immune-related genes of prophenoloxidase (PHE), anti-lipopolysaccharide factor (ALF), Lectin H (LecH), and prophenoloxidase-activating factor (PPAF) in both muscle and hepatopancreas in the RNAi group. Further tissue composition analysis showed that there were no significant differences in amino acid composition between the RNAi and control groups in muscle and hepatopancreas, but most of significant differences in fatty acid composition were detected between the two groups in both muscle and hepatopancreas. This study demonstrated that Es-MSTN is a vital muscle growth inhibition factor and displayed diverse function in participating in energy metabolism and immune response in E. sinensis.

Abstract Background Lipoxygenases (LOXs) play significant roles in abiotic stress responses, and identification of LOX gene promoter function can make an important contribution to elucidating resistance mechanisms. Here, we cloned the CmLOX08 promoter of melon (Cucumis melo) and identified the main promoter regions regulating transcription in response to signalling molecules and abiotic stresses. Results The 2054-bp promoter region of CmLOX08 from melon leaves was cloned, and bioinformatic analysis revealed that it harbours numerous cis-regulatory elements associated with signalling molecules and abiotic stress. Five 5′-deletion fragments obtained from the CmLOX08 promoter—2054 (LP1), 1639 (LP2), 1284 (LP3), 1047 (LP4), and 418 bp (LP5)—were fused with a GUS reporter gene and used for tobacco transient assays. Deletion analysis revealed that in response to abscisic acid, salicylic acid, and hydrogen peroxide, the GUS activity of LP1 was significantly higher than that of the mock-treated control and LP2, indicating that the − 2054- to − 1639-bp region positively regulates expression induced by these signalling molecules. However, no deletion fragment GUS activity was induced by methyl jasmonate. In response to salt, drought, and wounding treatments, LP1, LP2, and LP4 promoted significantly higher GUS expression compared with the control. Among all deletion fragments, LP4 showed the highest GUS expression, indicating that − 1047 to − 1 bp is the major region regulating promoter activity and that the − 1047 to − 418-bp region positively regulates expression induced by salt, drought, and wounding, whereas the − 1284 to − 1047-bp region is a negative regulatory segment. Interestingly, although the GUS activity of LP1 and LP2 was not affected by temperature changes, that of LP3 was significantly induced by heat, indicating that the − 1284- to − 1-bp region is a core sequence responding to heat and the − 2054- to − 1284-bp region negatively regulates expression induced by heat. Similarly, the − 1047- to − 1-bp region is the main sequence responding to cold, whereas the − 2054- to − 1047-bp region negatively regulates expression induced by cold. Conclusions We cloned the CmLOX08 promoter and demonstrated that it is a signalling molecule/stress-inducible promoter. Furthermore, we identified core and positive/negative regulatory regions responding to three signalling molecules and five abiotic stresses.

Vacuolar ATPase (V-ATPase) is a proton pump driven by ATP hydrolysis, and it plays an important role in numerous biological processes, such as protein degradation and synthesis, cell growth, and cell autophagy. The V-ATPase subunit B (VATB) is a conservative and regulatory subunit required for ATP hydrolysis during proton pumping. The VATB of Eriocheir sinensis (EsVATB), which includes an open reading frame (ORF) length of 1467 bp encoding 489 amino acids, was cloned to unveil the biological function of VATB during the molting process of crustaceans. Spatial and temporal expression profiles showed that EsVATB was highly expressed in the posterior gill accompanied with the highest osmotic pressure in the premolt (PrM) stage. Meanwhile, the highest expression level of EsVATB was identified in the hepatopancreas and heart during the postmolt stage and epidermis in the intermolt stage, indicating that EsVATB may perform diverse biological functions in different tissues during the molting process. The individual crabs in the interference group showed a high mortality rate (74%) and a low molting rate (26%) and failed to form a new epicuticle in the PrM stage. Meanwhile, a significant difference in osmotic pressure was identified between the interference and control groups. Our results indicate that EsVATB is an indispensable functional gene that may participate in osmoregulation and help with the new epicuticle formation during the molting process of E. sinensis.

Abstract Background Sexual precocity is a common biological phenomenon in animal species. A large number of precocity individuals were identified in Chinese mitten crab Eriocheir sinensis, which caused huge economic loss annually. However, the underlying genetic basis of precocity in E. sinensis remains unclear to date. Results In this study, morphological and histological observation and comparative transcriptome analysis were conducted among different stages of precocious one-year-old and normal two-year-old sexually mature E. sinensis. The expression profiles of the ovary, hepatopancreas, and eyestalk tissues were presented and compared. Genes associated with lipid metabolic process, lipid transport, vitelline membrane formation, vitelline synthesis, and neuropeptide hormone-related genes were upregulated in the ovary, hepatopancreas, and eyestalk of precocious E. sinensis. Our results indicated that the eyestalk was involved in the neuroendocrine system providing neuropeptide hormones that may induce vitellogenesis in the hepatopancreas and further stimulate ovary development. The hepatopancreas is a site for energy storage and vitellogenin synthesis, and it may assist oogenesis through lipid transport in precocious E. sinensis. Conclusion We provided not only an effective and convenient phenotype measurement method for the identification of potential precocious E. sinensis detection but also valuable genetic resources and novel insights into the molecular mechanism of precocity in E. sinensis. The genetic basis of precocity in E. sinensis is an integrated gene regulatory network of eyestalk, hepatopancreas, and ovary tissues.

Heterosis is a widespread biological phenomenon in fishes, in which hybrids have superior traits to parents. However, the underlying molecular basis for heterosis remains uncertain. Heterosis in growth and survival rates is apparent in hybrid tilapia (Oreochromis niloticus ♀ × O. aureus ♂). Comparisons of growth and hematological biochemical characteristics and mRNA and miRNA transcriptional analyses were performed in hybrid and parents tilapia stocks to investigate the underlying molecular basis for heterosis. Growth characteristics and hematological glucose and cholesterol parameters were significantly improved in hybrids. Of 3097 differentially expressed genes (DEGs) and 120 differentially expressed miRNAs (DEMs) identified among three stocks (O. niloticus, O. aureus, and hybrids), 1598 DEGs and 62 DEMs were non-additively expressed in hybrids. Both expression level dominance and overdominance patterns occurred for DEGs and DEMs, indicating that dominance and overdominance models are widespread in the transcriptional and post-transcriptional regulation of genes involved in growth, metabolism, immunity, and antioxidant capacity in hybrid tilapia. Moreover, potential negative regulation networks between DEMs and predicted target DEGs revealed that most DEGs from miRNA-mRNA pairs are up-regulated. Dominance and overdominance models in levels of transcriptome and miRNAome facilitate the integration of advantageous parental alleles into hybrids, contributing to heterosis of growth and improved survival. The present study provides new insights into molecular heterosis in hybrid tilapia, advancing our understanding of the complex mechanisms involved in this phenomenon in aquatic animals.

Geographical populations of Culter alburnus inhabiting different regions of China present substantial differences in their reproduction and development characters. This study compared the intestinal structures, digestive enzyme activities, and intestinal microbiomes in the Xingkai (XK) Lake and the Dianshan (DS) Lake populations of C. alburnus collected in two isolated and contrasting river systems. We wanted to discover whether the intestinal structure and functional divergence were formed in the two populations due to adaptive evolution caused by geographical isolation. Our study indicated that higher intestinal villi, thicker intestinal mucosa layer and intestinal muscle layer, and significantly higher activity of α-amylase were identified in the XK population. Moreover, quite different intestinal microbiomes were presented in the two populations, with the higher abundance of Bacteroidetes and Firmicutes in the XK population. The significantly different intestinal microbiome in the XK population was functionally enriched in carbohydrate, lipid, and amino acid metabolism by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Our findings indicated that substantial adaptative divergence in the intestinal structures and intestine microbiomes was formed in the two populations due to long-term geographical isolation, which may have strongly affected the digestion and absorption ability of the XK population compared with the DS population.

To reveal the evolutionary relationship of three mitten crabs (Eriocheir sinensis, E. hepuensis, and E. japonica), complete mitogenomes and nuclear 5S rDNA sequences were analyzed. Sequencing revealed that the mitogenomes analyzed shared conserved organization of the coding and non-coding regions but genetic variation was identified. Among the three mitten crabs distinct tandem repeats were identified in the mitochondrial D-loop region. The 5S gene (5S rDNA) sequence was highly conserved across the three species, whereas non-transcribed spacer (NTS) region exhibit high levels of variation including insertions, deletions and point mutations. Cluster analysis suggested that the three mitten crabs had their own independent 5S rDNA sequence variation and evolutionary pattern. Both mitogenome and 5S rDNA sequence analysis revealed significant genetic variation across the mitten crabs species. Phylogenetic analysis using mitogenome and 5S rDNA sequences demonstrated that E. japonica was relatively more distant from E. sinensis and E. hepuensis. This study extended our previous knowledge and confirmed that the three mitten crabs are likely to be genetically differentiated species. In addition, our study also provided insights into the conservation of pure natural resources of E. sinensis, an important aquaculture species.