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Liparis gigantea is a Chinese traditional medicinal herb in the Orchidaceae family. It is a rare and special Liparis species that exhibits relatively large flowers. To illuminate its phylogenetic status and augment genomic resources, the complete chloroplast (cp) genome of L. gigantea was first sequenced and assembled using whole genome next-generation sequencing in this study. The cp genome size is 158,462 bp with a total GC content of 36.9%. Characterized by a quadripartite structure, the genome consists of a large single-copy (LSC) region of 86,032 bp, a small single-copy (SSC) region of 18,322 bp, which is separated by a pair of 27,054 bp inverted repeat regions (IRs). A total of 133 genes were annotated, including 87 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic analysis strongly supported L. gigantea as the sister to two closely related terrestrial species, Liparis nervosa and L. vivipara. The results of this study provide genomic information for future research and application of this medicinal herb.

Soil salinity, a major environmental stress, restricts agricultural production worldwide. Gynura divaricata (L.) DC. is widely cultivated on tropical islands in China and has both edible and medicinal value. NaCl stress and growth indicators, antioxidant enzyme activity, as well as MDA, proline, and soluble sugar content, were determined. Based on the transcriptomic data of tissue-cultured G. divaricata plantlets grown in control (0 mM NaCl) and salt stress (50 and 200 mM NaCl) conditions, gene expression patterns were examined. KEGG enrichment analysis of differentially expressed genes indicated significant enrichment of plant hormone signaling, MAPK signaling, and starch and sucrose metabolism pathways. These findings allowed key biological pathways and salt stress-responsive genes to be identified, thus providing a molecular basis for breeding salt-tolerant G. divaricata varieties. This transcriptomic analysis revealed a complex tolerance mechanism of G. divaricata in response to NaCl, laying a foundation for screening and cloning key genes related to NaCl tolerance and studying their interactions. These findings would allow the molecular basis of NaCl tolerance to be explored, with the aim of breeding NaCl-tolerant varieties.

Abstract MeFtsZ2-1 is a key gene for plant plastid division, but the mechanism by which MeFtsZ2-1 affects pigment accumulation in cassava (Manihot esculenta Crantz) through plastids remains unclear. We found that MeFtsZ2-1 overexpression in cassava (OE) exhibited darker colors of leaves, with increased levels of anthocyanins and carotenoids. Further observation via Transmission Electron Microscopy (TEM) revealed no apparent defects in chloroplast structure but an increase in the number of plastoglobule in OE leaves. RNA-seq results showed 1582 differentially expressed genes (DEGs) in leaves of OE. KEGG pathway analysis indicated that these DEGs were enriched in pathways related to flavonoid, anthocyanin, and carotenoid biosynthesis. This study reveals the role of MeFtsZ2-1 in cassava pigment accumulation from a physiological and transcriptomic perspective, providing a theoretical basis for improving cassava quality.

Abstract Background Dalbergia odorifera is a rare and precious rosewood specie, which is valued for its amber tones, abstract figural patterns, and impermeability to water and insects. However, the information on genetic diversity and marker-assisted selection breeding of D. odorifera is still limited. Simple sequence repeat (SSR) markers are an ideal tool for genetic diversity analysis and marker-assisted molecular breeding for complex traits. Results Here, we have developed SSR markers within candidate genes and used them to explore the genetic diversity among D. odorifera germplasm resources. A total of 635 SSR loci were identified. The proportions of mono-, di- and tri-nucleotide repeat motifs were 52.28%, 22.99% and 21.42%, respectively. From these, a total of 114 SSR primers were synthesized, of which 24 SSR markers displayed polymorphism (polymorphic information content (PIC) > 0.25). Subsequently, these polymorphic markers were used for the genetic diversity analysis of 106 D. odorifera individuals from 11 natural populations. According to the genetic diversity analysis of D. odorifera natural populations, the average observed heterozygosity (Ho) was 0.500, the average expected heterozygosity (He) was 0.524, and the average Shannon’s information index (I) was 0.946. These indicated that the natural populations had moderate genetic diversity. AMOVA analysis showed that 5% of the total variation was within the individuals of a population, whereas 95% of the variation was among the individuals of the populations, indicating a high degree of genetic variation between populations. On the basis of their genetic structures, these populations could be divided into four groups. Conclusions Our study provides important experimental resources for genetic studies and assists in the program of molecular breeding of D. odorifera wood formation.

Hippeastrum, a highly diverse genus in the Amaryllidaceae family, is a valuable ornamental bulbous flowering plant. Somatic embryogenesis (SE) is an efficient method for mass production of Hippeastrum plantlets. Previous studies have been devoted to the in vitro propagation of Hippeastrum, but the SE and its regulatory networks are rarely reported. In this study, we established a direct SE method of Hippeastrum ‘Bangkok Rose’ using leaf bases as explants. MS supplemented with 1.00 mg · L−1 NAA +1.00 mg · L−1 KT + 0.25 mg · L−1 TDZ was the optimal medium for SE. Histological observations showed that the bipolar somatic embryo originated from the epidermal cell layer and underwent initiation, globular, scutellar and coleoptile stages. During SE, endogenous hormones of IAA, CTK, ABA, and SA were highly accumulated. Transcriptomic analysis revealed the genes encoding auxin biosynthesis/metabolic enzymes and efflux carriers were induced, while the auxin receptor of TIR1 and ARF transcriptional repressor of Aux/IAA were down-regulated and up-regulated, respectively, leading to suppression of auxin signaling. In contrast, cytokine signaling was promoted at the early stage of SE, as biosynthesis, transport, and signaling components were up-regulated. Various stress-related genes were up-regulated at the early or late stages of SE. Chromatin remodeling could also be dynamically regulated via distinct expression enzymes that control histone methylation and acetylation during SE. Moreover, key SE regulators, including WOXs and SERKs were highly expressed along with SE. Overall, the present study provides insights into the SE regulatory mechanisms of the Hippeastrum.

Abstract During postharvest storage, the metabolism of cell wall components greatly affects the quality of fruits and vegetables. Utilizing 1‐methylcyclopropene (1‐MCP) as an ethylene receptor inhibitor and modified atmosphere (MA) separately or in combination (1‐MCP+MA) were investigated for their impact on Zizania latifolia quality during postharvest storage. The treatments effectively controlled firmness increase, color degradation, and reductions in soluble protein, reducing sugar, total phenol, and ascorbic acid content, with the combined 1‐MCP+MA showing the most significant effect. These treatments also moderately changed soluble pectin, protopectin, cellulose, and hemicellulose content, preserving the activities of essential enzymes and the expression of enzyme genes. The combined treatment particularly demonstrated superior preservation capabilities, holding promise for reducing postharvest losses and maintain the storage quality of edible produce, offering insights for efficient postharvest storage and freshness maintenance of fruits and vegetables.

Abstract Background The orchids of the subtribe Coelogyninae are among the most morphologically diverse and economically important groups within the subfamily Epidendroideae. Previous molecular studies have revealed that Coelogyninae is an unambiguously monophyletic group. However, intergeneric and infrageneric relationships within Coelogyninae are largely unresolved. There has been long controversy over the classification among the genera within the subtribe. Results The complete chloroplast (cp.) genomes of 15 species in the subtribe Coelogyninae were newly sequenced and assembled. Together with nine available cp. genomes in GenBank from representative clades of the subtribe, we compared and elucidated the characteristics of 24 Coelogyninae cp. genomes. The results showed that all cp. genomes shared highly conserved structure and contained 135 genes arranged in the same order, including 89 protein-coding genes, 38 tRNAs, and eight rRNAs. Nevertheless, structural variations in relation to particular genes at the IR/SC boundary regions were identified. The diversification pattern of the cp. genomes showed high consistency with the phylogenetic placement of Coelogyninae. The number of different types of SSRs and long repeats exhibited significant differences in the 24 Coelogyninae cp. genomes, wherein mononucleotide repeats (A/T), and palindromic repeats were the most abundant. Four mutation hotspot regions (ycf1a, ndhF-rp132, psaC-ndhE, and rp132-trnL) were determined, which could serve as effective molecular markers. Selection pressure analysis revealed that three genes (ycf1a, rpoC2 and ycf2 genes) might have experienced apparent positive selection during the evolution. Using the alignments of whole cp. genomes and protein-coding sequences, this study presents a well-resolved phylogenetic framework of Coelogyninae. Conclusion The inclusion of 55 plastid genome data from a nearly complete generic-level sampling provide a comprehensive view of the phylogenetic relationships among genera and species in subtribe Coelogyninae and illustrate the diverse genetic variation patterns of plastid genomes in this species-rich plant group. The inferred relationships and informally recognized major clades within the subtribe are presented. The genetic markers identified here will facilitate future studies on the genetics and phylogeny of subtribe Coelogyninae.

Abstract Santalum album is a well-known aromatic and medicinal plant that is highly valued for the essential oil (EO) extracted from its heartwood. In this study, we present a high-quality chromosome-level genome assembly of S. album after integrating PacBio Sequel, Illumina HiSeq paired-end and high-throughput chromosome conformation capture sequencing technologies. The assembled genome size is 207.39 M with a contig N50 of 7.33 M and scaffold N50 size of 18.31 M. Compared with three previously published sandalwood genomes, the N50 length of the genome assembly was longer. In total, 94.26% of the assembly was assigned to 10 pseudo-chromosomes, and the anchor rate far exceeded that of a recently released value. BUSCO analysis yielded a completeness score of 94.91%. In addition, we predicted 23,283 protein-coding genes, 89.68% of which were functionally annotated. This high-quality genome will provide a foundation for sandalwood functional genomics studies, and also for elucidating the genetic basis of EO biosynthesis in S. album.

Between 2023 and 2024, a type of green alga was observed for the first time settling on Oil-tea Camellia leaves and branches in the eastern Oil-tea Camellia planting area of Hainan Island, forming a layer of gray-green moss with a rough surface that seriously interfered with the leaves’ normal photosynthesis. To further research the issue, this study used the plant photosynthesis measurement system and the paraffin sectioning technique to compare and analyze the changes in photosynthetic characteristics and anatomical structure of healthy and green algal-covered Oil-tea Camellia leaves. At the same time, the algal strain was effectively separated and purified using the plate delineation method, and its species classification was determined by combining morphological observation and molecular identification based on SSU-ITS sequences. The results of the study demonstrated that the coating of green alga facilitated the lignification of the leaf’s epidermal cell walls. After being covered by the green alga, the intercellular CO2 concentration (Ci) increased significantly by 21.5%, while the net photosynthetic rate (Pn), transpiration rate (Tr), and stomatal conductance (Gs) all significantly decreased by 72.8%, 30.4%, and 24.9%, respectively. More specifically, the green alga that covers the leaves of Oil-tea Camellia was identified as Desmodesmus armatus of Chlorophyta. Notably, the green alga had a long growth cycle, did not undergo a decline phase within one month, had an optimal growth pH of 11.0, and could flourish in excessively alkaline conditions. In conclusion, this study not only reported for the first time the phenomena of D. armatus infesting Oil-tea Camellia leave, but also showed its unique physiological and ecological properties, providing a foundation for future research on relevant prevention and control approaches.

Abstract Background Cultivated Hippeastrum × hybridum is a popular ornamental plant with large and colorful flowers, long flowering duration, and high commercial value. As its main ornamental feature, its flower color is related to the anthocyanin content in the tepals. However, the molecular regulatory mechanisms of anthocyanin biosynthesis in H. × hybridum have not yet been elucidated. Results In the present study, 12 cDNA libraries of four stages of H.× hybridum ‘Royal Velvet’ tepal development were used for RNA-seq, obtaining 79.83 gigabases (GB) of clean data. The data were assembled into 148,453 unigenes, and 11,262 differentially expressed genes were identified. Forty key enzymes participating in anthocyanin biosynthesis were investigated, and the results showed that most of the anthocyanin structural genes were expressed at low levels in S1 and were markedly upregulated in S2 and S3. The expression profiles of 12 selected genes were verified by qRT-PCR. Furthermore, the R2R3-MYB transcription factor (TF), HpMYB1, involved in the regulation of anthocyanin biosynthesis was identified by sequence, expression pattern, and subcellular localization analyses. Its overexpression in tobacco significantly increased the anthocyanin levels in various tissues and activated anthocyanin-related genes. Conclusions Using RNA-seq technology, we successfully identified a potential R2R3-MYB gene, HpMYB1, that regulates anthocyanin biosynthesis in H.× hybridum ‘Royal Velvet’. Our findings provide basic transcript information and valuable transcriptome data for further identification of key genes involved in anthocyanin biosynthesis and can be applied in the artificial breeding of new H. × hybridum cultivars with enhanced ornamental value.

Phalaenopsis orchids, with their unique appearance and extended flowering period, are among the most commercially valuable Orchidaceae worldwide. Particularly, the variegation in leaf color of Phalaenopsis significantly enhances the ornamental and economic value and knowledge of the molecular mechanism of leaf-color variegation in Phalaenopsis is lacking. In this study, an integrative analysis of the physiology, cytology, and transcriptome profiles was performed on Phalaenopsis Chia E Yenlin Variegata leaves between the green region (GR) and yellow region (YR) within the same leaf. The total chlorophyll and carotenoid contents in the YR exhibited a marked decrease of 72.18% and 90.21%, respectively, relative to the GR. Examination of the ultrastructure showed that the chloroplasts of the YR were fewer and smaller and exhibited indistinct stromal lamellae, ruptured thylakoids, and irregularly arranged plastoglobuli. The transcriptome sequencing between the GR and YR led to a total of 3793 differentially expressed genes, consisting of 1769 upregulated genes and 2024 downregulated genes. Among these, the chlorophyll-biosynthesis-related genes HEMA, CHLH, CRD, and CAO showed downregulation, while the chlorophyll-degradation-related gene SGR had an upregulated expression in the YR. Plant-hormone-related genes and transcription factors MYBs (37), NACs (21), ERFs (20), bHLH (13), and GLK (2), with a significant difference, were also analyzed. Furthermore, qRT-PCR experiments validated the above results. The present work establishes a genetic foundation for future studies of leaf-pigment mutations and may help to improve the economic and breeding values of Phalaenopsis.

Abstract Background The orchid genus Pholidota Lindl. ex Hook. is economically important as some species has long been used in traditional medicine. However, the systematic status of the genus and intergeneric relationships inferred from previous molecular studies are unclear due to insufficient sampling and lack of informative sites. So far, only limited genomic information has been available. The taxonomy of Pholidota remains unresolved and somewhat controversial. In this study, the complete chloroplast (cp.) genomes of thirteen Pholidota species were sequenced and analyzed to gain insight into the phylogeny of Pholidota and mutation patterns in their cp. genomes. Results All examined thirteen Pholidota cp. genomes exhibited typical quadripartite circular structures, with the size ranging from 158,786 to 159,781 bp. The annotation contained a total of 135 genes in each cp. genome, i.e., 89 protein-coding genes, 38 tRNA genes, and eight rRNA genes. The codon usage analysis indicated the preference of A/U-ending codons. Repeat sequence analysis identified 444 tandem repeats, 322 palindromic repeats and 189 dispersed repeats. A total of 525 SSRs, 13,834 SNPs and 8,630 InDels were detected. Six mutational hotspots were identified as potential molecular markers. These molecular markers and highly variable regions are expected to facilitate future genetic and genomic studies. Our phylogenetic analyses confirmed the polyphyletic status of the genus Pholidota, with species grouped into four main clades: Pholidota s.s. was resolved as the sister to a clade containing species of Coelogyne; the other two clades clustered together with species of Bulleyia and Panisea, respectively; species P. ventricosa was placed at the basal position, deviated from all other species. Conclusion This is the first study to comprehensively examine the genetic variations and systematically analyze the phylogeny and evolution of Pholidota based on plastid genomic data. These findings contribute to a better understanding of plastid genome evolution of Pholidota and provide new insights into the phylogeny of Pholidota and its closely related genera within the subtribe Coelogyninae. Our research has laid the foundation for future studies on the evolutionary mechanisms and classification of this economically and medicinally important genus.

With the rapid development of urbanization, China is facing problems, such as uncoordinated regional development, imbalanced land space development, and ecological environment pollution. This poses a huge threat to the sustainable development of China’s economy and society. Therefore, there is an urgent need to determine how to coordinate the relationship between the space exploitation, economic development, and ecological environment (SEE) of urban areas. In this study, taking the Henan Province as an example, long time-series data (2000–2020) were used, at a city scale. Then, we developed a logical framework to reveal the interrelationship and intrinsic mechanism between SEE. Next, we explored the spatiotemporal coupling characteristics of SEE using a linear weighting method and a coupling coordination analysis. We found that, from 2000 to 2020, the comprehensive level of SEE showed an obvious trend of change, and different cities have different coupling coordination degrees. However, the overall coupling coordination level is steadily developing and tending to improve. Furthermore, with the spatial autocorrelation method, we analyzed spatial correlation patterns and collaboration/trade-off relationships for SEE. Through the analysis, positive correlation types (HH, LL) cluster significantly and negative correlation types (HL, LH) have low clustering. Meanwhile, we found significant spatial differences in cooperation/trade-off relationships between different years. This research can serve as a reference and as methodological guidance for achieving coordination and sustainable development of the economy, space, and environment.

Abstract Background Aglaonema commutatum ‘Red Valentine’, as a foliage ornamental plant, is widely used for interior and exterior decoration because of its easy cultivation and management. However, reduced proportion of red foliage during large-scale production of A. commutatum seedlings is a frequent occurrence, which has considerable implications on the plant’s ornamental and market value. However, the molecular mechanisms underlying this phenomenon remain unclear. Results To explore the molecular basis of the variation in leaf color of A. commutatum Red Valentine, we performed transcriptome sequencing with the Illumina platform using two different varieties of A. commutatum, namely Red Valentine and a green mutant, at three different stages of leaf development. We annotated 63,621 unigenes and 14,186 differentially expressed genes by pairwise comparison. Furthermore, we identified 26 anthocyanin biosynthesis structural genes. The transcript per million (TPM) values were significantly higher for Red Valentine than for the green mutant in all three developmental stages, consistent with the high anthocyanin content of Red Valentine leaves. We detected positive transcription factors that may be involved in the regulation of anthocyanin biosynthesis using BLAST and through correlation analysis. Downregulation of these transcription factors may downregulate the expression of anthocyanin genes. We obtained full-length cDNA of the anthocyanin biosynthesis and regulatory genes and constructed phylogenetic trees to ensure accuracy of the analysis. Conclusions Our study provides insights into the molecular mechanisms underlying leaf variation in A. commutatum Red Valentine and may be used to facilitate the breeding of ornamental cultivars with high anthocyanin levels.

Abstract Euryodendron excelsum H.T. Chang is a rare and endangered woody plant endemic to China. It is very important to conserve and propagate this species from extinction. In this study, leaves and petioles from the axillary shoots in vitro were used as explants to culture on the different plant growth regulator (PGR) woody plant medium (WPM) and establish an efficient shoot proliferation and plant regeneration system. WPM supplemented with 1.0 mg/L 2,4-D induced callus dedifferentiated into buds and somatic embryos on various media,including PGR-free WPM. However, only adventitious shoots formed on WPM with 1.0 mg/L of cytokinins such as 6-benzyladenine (BA), kinetin (KIN) or thidiazuron (TDZ). When another cytokinin, zeatin, was used, somatic embryos were induced directly from From cut surface of these explants. Adventitious roots could be induced from both explants on WPM with 1.0 mg/L α-naphthaleneacetic acid (NAA). Somatic embryos cultured in PGR-free WPM or WPM with 0.2 mg/L NAA developed roots. Plantlets derived from somatic embryos were transferred to a peat: sand (1:1, v/v) substrate, and showed survival rates of 64.3% at 30 days and 54.6% at 90 days. Callus clumps with adventitious shoot buds that were transferred to WPM containing 1.0 mg/L BA and 0.2 mg/L NAA generated a mean 3.3 multiple shoots. Callus-derived shoots regenerated and rooted successfully (100%) on agar-free vermiculite-based WPM with 0.5 μM NAA after 30 d. Plantlets transplanted to peat soil: vermiculite (1:1, v/v) displayed the highest survival (96.7%) after three months.

Abstract Background Oguchi disease is a rare autosomal recessive form of congenital quiescent night blindness. Oguchi disease has been found to be associated with gene mutations in SAG and GRK1, which are vital factors in the recovery phase of phototransduction after light stimuli. We report a case of Oguchi disease with novel heterozygous mutations in SAG. Case presentation A 7-year-old girl with a history of night blindness since childhood, was referred to our hospital. Ophthalmologic examinations included visual acuity, fundus examinations, fundus photography, spectral-domain optical coherence tomography, electroretinographic (ERG). Mutation screening of the SAG and GRK1 genes was performed. This patient exhibited typical clinical characteristics of Oguchi disease, including night blindness, golden fundus with the Mizuo–Nakamura phenomenon, packed structure of the parafovea in optical coherence tomography and reduced a-waves and b-waves in scotopic 3.0 ERG. Genetic testing revealed a heterozygous change in nucleotide c.72_75+15delATCGGTGAGTGGTGCACAA in exon 2 of the SAG gene in this patient, her unaffected mother and younger brother. A splicing alteration of nucleotide c.376-2A>C was identified in exon 6 of the SAG gene with heterozygous status in this patient and her unaffected father. Conclusions Compound heterozygosity of a nonsense p.S25X mutation in exon 2 and a splicing alteration in exon 6 of the SAG gene is the cause of this patient with Oguchi type 1 disease in China.

Orchid seeds lack endosperms and depend on mycorrhizal fungi for germination and nutrition acquisition under natural conditions. Piriformospora indica is a mycorrhizal fungus that promotes seed germination and seedling development in epiphytic orchids, such as Dendrobium nobile. To understand the impact of P. indica on D. nobile seed germination, we examined endogenous hormone levels by using liquid chromatography–mass spectrometry. We performed transcriptomic analysis of D. nobile protocorm at two developmental stages under asymbiotic germination (AG) and symbiotic germination (SG) conditions. The result showed that the level of endogenous IAA in the SG protocorm treatments was significantly higher than that in the AG protocorm treatments. Meanwhile, GA3 was only detected in the SG protocorm stages. IAA and GA synthesis and signaling genes were upregulated in the SG protocorm stages. Exogenous GA3 application inhibited fungal colonization inside the protocorm, and a GA biosynthesis inhibitor (PAC) promoted fungal colonization. Furthermore, we found that PAC prevented fungal hyphae collapse and degeneration in the protocorm, and differentially expressed genes related to cell wall metabolism were identified between the SG and AG protocorm stages. Exogenous GA3 upregulated SRC2 and LRX4 expression, leading to decreased fungal colonization. Meanwhile, GA inhibitors upregulated EXP6, EXB16, and EXP10-2 expression, leading to increased fungal colonization. Our findings suggest that GA regulates the expression of cell wall metabolism genes in D. nobile, thereby inhibiting the establishment of mycorrhizal symbiosis.

For high-resolution remote sensing image retrieval tasks, single-scale features cannot fully express the complexity of the image information. Due to the large volume of remote sensing images, retrieval requires extensive memory and time. Hence, the problem of how to organically fuse multi-scale features and enhance retrieval efficiency is yet to be resolved. We propose an end-to-end deep hash remote sensing image retrieval model (PVTA_MSF) by fusing multi-scale features based on the Pyramid Vision Transformer network (PVTv2). We construct the multi-scale feature fusion module (MSF) by using a global attention mechanism and a multi-head self-attention mechanism to reduce background interference and enhance the representation capability of image features. Deformable convolution is introduced to address the challenge posed by varying target orientations. Moreover, an intra-class similarity (ICS) loss is proposed to enhance the discriminative capability of the hash feature by minimizing the distance among images of the same category. The experimental results show that, compared with other state-of-the-art methods, the proposed hash feature could yield an excellent representation of remote sensing images and improve remote sensing image retrieval accuracy. The proposed hash feature can gain an increase of 4.2% and 1.6% in terms of mAP on the UC Merced and NWPU-RESISC45 datasets, respectively, in comparison with other methods.

Background. CD47 has high levels of expression in malignant cancer cells, which binds to SIRP-α to release the “don’t eat me” signal and prevents mononuclear macrophages from phagocytosing the cells. Resistance to drugs and metastases are potential barriers for prostate cancer endocrine therapy. Although immunotherapy for tumors has developed rapidly in the last few decades, its effectiveness in treating prostate cancer is unsatisfactory. Prostate cancer has a high-expression level of CD47. Therefore, a novel approach for potential immunotherapy may be provided by investigating the relationship among CD47 and the infiltration of immune cells in the prostate carcinoma. Methods. The GEPIA database was utilized to compare the abundance of CD47 in malignant tissues with tissues that were normal. Furthermore, the function of CD47 in prostate carcinoma was assessed by CancerSEA. The association among CD47 and the tumor microenvironment was assessed utilizing the TISCH single cell data database. By using TIMER, the connection among CD47 and immunological invasion of prostate cancer was explored. Moreover, macrophages were cocultured with mouse prostate cancer cell RM-1 blocked by CD47 antibody to observe the changes in phagocytosis efficiency in vitro. Results. Expression level of CD47 is upregulated in prostate carcinoma, and it is closely connected with prostate cancer’s inadequate immune invasion. CD47 antibody blocking promotes macrophage phagocytosis of RM-1. Conclusion. Our research demonstrates a closely relationship among CD47 and the immunological microenvironment of prostate cancer, and blocking CD47 can promote macrophages to phagocytosis of prostate cancer cells. Therefore, CD47 may provide novel strategies for potential immunotherapy of prostate cancer.

The tight coupling of shape transformation, stiffness tuning, and self‐sensing that biological organisms exhibit has long served as inspiration for next‐generation soft robots. However, most current soft robots rely on intrinsically soft materials for actuation, separately embedded sensors for sensing, and have fixed stiffness once fabricated. Large gaps remain between these soft robots and biological organisms where multifunctionality is realized within an integrated body. Herein, a new class of robotic structures from architectured particle assemblies is introduced. They combine three functions: shape changing, stiffness variation, and self‐sensing into one monolithic structure. Unlike traditional entirely soft robots, the design utilizes the geometric contacts of stiff, architectured particles under confining pressure to achieve these functions. The applications of these structures by designing smart self‐sensing architectures and soft grippers are demonstrated. The design provides a new paradigm of multifunctional robotic structures, with potential multiscale applications in adaptive robots, smart devices, and reconfigurable architectures.

BackgroundThe clinical outcome of triple-negative breast cancer (TNBC) is poor. Finding more targets for the treatment of TNBC is an urgent need. SENPs are SUMO-specific proteins that play an important role in SUMO modification. Among several tumor types, SENPs have been identified as relevant biomarkers for progression and prognosis. The role of SENPs in TNBC is not yet clear.MethodsThe expression and prognosis of SENPs in TNBC were analyzed by TCGA and GEO data. SENP3 coexpression regulatory networks were determined by weighted gene coexpression network analysis (WGCNA). Least absolute shrinkage and selection operator (LASSO) and Cox univariate analyses were used to develop a risk signature based on genes associated with SENP3. A time-dependent receiver operating characteristic (ROC) analysis was employed to evaluate a risk signature’s predictive accuracy and sensitivity. Moreover, a nomogram was constructed to facilitate clinical application.ResultsThe prognostic and expression effects of SENP family genes were validated using the TCGA and GEO databases. SENP3 was found to be the only gene in the SENP family that was highly expressed and associated with an unfavorable prognosis in TNBC patients. Cell functional experiments showed that knockdown of SENP3 leads to growth, invasion, and migration inhibition of TNBC cells in vitro. By using WGCNA, 273 SENP3-related genes were identified. Finally, 11 SENP3-related genes were obtained from Cox univariate analysis and LASSO regression. Based on this, a prognostic risk prediction model was established. The risk signature of SENP3-related genes was verified as an independent prognostic marker for TNBC patients.ConclusionAmong SENP family genes, we found that SENP3 was overexpressed in TNBC and associated with a worse prognosis. SENP3 knockdown can inhibit tumor proliferation, invasion, and migration. In TNBC patients, a risk signature based on the expression of 11 SENP3-related genes may improve prognosis prediction. The established risk markers may be promising prognostic biomarkers that can guide the individualized treatment of TNBC patients.

Abstract Background Paphiopedilum, commonly known as slipper orchid, is an important genus of orchid family with prominent horticultural value. Compared with conventional methods such as tillers and in vitro shoots multiplication, induction and regeneration of protocorm-like bodies (PLBs) is an effective micropropagation method in Paphiopedilum. The PLB initiation efficiency varies among species, hybrids and varieties, which leads to only a few Paphiopedilum species can be large-scale propagated through PLBs. So far, little is known about the mechanisms behind the initiation and maintenance of PLB in Paphiopedilum. Results A protocol to induce PLB development from seed-derived protocorms of Paphiopedilum SCBG Huihuang90 (P. SCBG Prince × P. SCBG Miracle) was established. The morphological characterization of four key PLB developmental stages showed that significant polarity and cell size gradients were observed within each PLB. The endogenous hormone level was evaluated. The increase in the levels of indoleacetic acid (IAA) and jasmonic acid (JA) accompanying the PLBs differentiation, suggesting auxin and JA levels were correlated with PLB development. Gibberellic acid (GA) decreased to a very low level, indicated that GA inactivation may be necessary for shoot apical meristem (SAM) development. Comparative transcriptomic profiles of four different developmental stages of P. SCBG Huihuang90 PLBs explore key genes involved in PLB development. The numbers of differentially expressed genes (DEGs) in three pairwise comparisons (A vs B, B vs C, C vs D) were 1455, 349, and 3529, respectively. KEGG enrichment analysis revealed that DEGs were implicated in secondary metabolite metabolism and photosynthesis. DEGs related to hormone metabolism and signaling, somatic embryogenesis, shoot development and photosynthesis were discussed in detail. Conclusion This study is the first report on PLB development in Paphiopedilum using transcriptome sequencing, which provides useful information to understand the mechanisms of PLB development.

Abstract Papillary thyroid cancer (PTC) is the main histological type of thyroid cancer and accounts for almost all increased cases worldwide. Patients with PTC exhibit a favorable prognosis, but the fact that PTC is often accompanied by a high prevalence of lymph node metastasis (LNM) means that the overall recurrence-free survival rate in PTC patients is relatively low. Herein, we identified that ID3 expression is subdued in PTC tissues and closely associated with LNM and a poor disease-free survival outcome in PTC patients. The main contributor to this gene repression is the hypermethylation of the CpG island at the promoter of ID3. Besides, we uncovered that a loss of ID3 promotes invasion and migration of PTC cells, while an ectopic overexpression of ID3 inhibits invasion and migration. Mechanistically, ID3 exhibits tumor suppressor functions in PTC cells by interacting with E47 to form heterodimers that prevent E47 binding to CDH1 promoter and maintaining CDH1 transcription and epithelial phenotype in PTC cells. Taken together, our study demonstrates that ID3 plays a tumor suppressor role in PTC and impedes metastasis by inhibiting E47-mediated epithelial to mesenchymal transition.

Aglaonema commutatum is one of the most popular foliage plants with abundant leaf phenotypes; therefore, anthocyanin coloration is a vital economic trait in A. commutatum. However, the molecular mechanisms underlying anthocyanin biosynthesis and its regulation remain unclear. In this study, AcMYB1 and AcbHLH1, transcription factor genes related to an R2R3-myeloblast (MYB) and a basic helix–loop–helix (bHLH), respectively, were isolated from A. commutatum “Red Valentine” and functionally characterized. AcMYB1 and AcbHLH1 were found to interact by Y2H and BiFC assay. AcMYB1 was grouped into the AN2 subgroup and shared high homology with the known regulators of anthocyanin biosynthesis. Gene expression analysis showed that both AcMYB1 and AcbHLH1 have similar expression patterns to anthocyanin structural genes and correlate with anthocyanin distribution in different tissues of A. commutatum. Light strongly promoted anthocyanin accumulation by upregulating the expression of anthocyanin-related genes in A. commutatum leaves. Ectopic expression of AcMYB1 in tobacco remarkably increased anthocyanin accumulation in both vegetative and reproductive tissues at various developmental stages. These results provide insights into the regulation of anthocyanin biosynthesis in A. commutatum and are useful for breeding new A. commutatum cultivars with enhanced ornamental value.

The search for charging electric vehicles using renewable energy sources and ensuring the stability of the electrical system has been growing. This has led to the development of charging stations that integrate photovoltaic systems, energy storage systems in batteries, and charging stations. The storage system allows for applications that increase the reliability of the electrical network. The objective of this work is to study, based on real operational scenarios, the impacts, and criteria of energy quality of a charging solution containing a photovoltaic system, a storage system, and a charging station. In the solution, the batteries are lead-carbon type and photovoltaics have priority in energy supply, using excess generation to charge the batteries. In this aspect, the work presents relevant contributions to the study of energy quality. An improvement in energy quality is pointed out with the use of batteries, proving that even in the most diverse operating situations, such as partial shading of the photovoltaic modules, with 20% shading relative to the nominal power, charging is not impacted and reductions in distortions are achieved, with a 50% reduction in voltage imbalance, when the storage system is a voltage reference and reference to the microgrid.

The genus Thuniopsis was recently proposed for a rare orchid species T. cleistogama formerly classified in the genus Thunia. The relationships between Thuniopsis and its related genera have not yet been conclusively resolved. Recognition of the genus provides a new perspective to illustrate the morphological diversity and plastome evolution within Coelogyninae. In this study, we sequenced and assembled complete chloroplast (cp) genomes for three accessions of Thuniopsis cleistogama and two accessions of Thunia alba. A total of 135 genes were annotated for each cp genome, including 89 protein-coding genes, 38 tRNA genes, and eight rRNA genes. The ENC-plot and neutrality plot analyses revealed that natural selection dominated over mutation pressure in their evolutionary process. Specially, we found that selection played a vital role in shaping the codon usage in Thunia alba cp genome. General characteristics of the cp genomes were further analyzed and compared with those published plastomes of four other related species. Despite the conserved organization and structure, the whole individual cp genome size ranged from 158,394 bp to 159,950 bp. In all the examined plastomes, sequences in the inverted repeat (IR) regions were more conserved than those in the small single copy (SSC) and large single copy (LSC) regions. However, close examination identified contraction and expansion of the IR/SSC boundary regions, which might be the main reason for the cp genome size variation. Our comparative analysis of the cp genomes revealed that single nucleotide polymorphisms (SNPs) and insertions/deletions (InDels) provided valuable information for identifying genetic variations within and among genera. Furthermore, sequence variations in the protein-coding regions were more conserved than those in the non-coding regions. We selected eight divergence hotspots with nucleotide sequence diversities (Pi values) higher than 0.08. Most of these polymorphisms were located in the intergenic regions. Phylogenomic analyses recovered largely congruent relationships among major clades and strongly supported the monophyly of Thuniopsis. The results obtained in this study can improve our understanding of the classification of this enigmatic genus. The chloroplast genomic data presented here provide valuable insights into the phylogeny and evolutionary patterns of the Coelogyninae as well as the orchids as a whole.

Abstract An efficient regeneration system via shoot organogenesis and somatic embryogenesis from in vitro leaf and root explants was established for Scaevola sericea for the first time. The highest axillary shoot proliferation coefficient (4.8) was obtained on Murashige and Skoog (MS) medium supplemented with 1.0 mg/L 6-benzyladenine (BA) and 0.1 mg/L α-naphthaleneacetic acid (NAA) every 45 days. Young in vitro leaves and roots, which were used as explants, were cultured onto medium supplemented with different plant growth regulators. Our results showed that only cytokinins BA and thidiazuron (TDZ), could induce adventitious shoots and somatic embryos from leaf and root explants. The optimal medium to achieve this was MS medium supplemented with 2.5 mg/L BA and which induced most adventitious shoots (2.7) and somatic embryos (17.3) from leaf explants within 30 days. From root explants, 1.1 adventitious shoots and 7.6 somatic embryos could be induced on MS medium supplemented with 2.5 mg/L TDZ. Histological observation showed that both somatic embryos and adventitious shoots were originated from homogeneous parenchyma and the development of somatic embryos was visible. Maximum rooting percentage (99.0%) was achieved on half-strength MS medium supplemented with 2.5 mg/L NAA. Well-rooted plantlets, which were transplanted into a substrate of pure river sand, displayed a high survival percentage of 91.7% after transplanting for 45 days while the best substrate for plantlet growth was river sand: coral sand (1:1).

Abstract Backgrounds Paphiopedilum is an important genus of the orchid family Orchidaceae and has high horticultural value. The wild populations are under threat of extinction because of overcollection and habitat destruction. Mature seeds of most Paphiopedilum species are difficult to germinate, which severely restricts their germplasm conservation and commercial production. The factors inhibiting germination are largely unknown. Results In this study, large amounts of non-methylated lignin accumulated during seed maturation of Paphiopedilum armeniacum (P. armeniacum), which negatively correlates with the germination rate. The transcriptome profiles of P. armeniacum seed at different development stages were compared to explore the molecular clues for non-methylated lignin synthesis. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that a large number of genes associated with phenylpropanoid biosynthesis and phenylalanine metabolism during seed maturation were differentially expressed. Several key genes in the lignin biosynthetic pathway displayed different expression patterns during the lignification process. PAL, 4CL, HCT, and CSE upregulation was associated with C and H lignin accumulation. The expression of CCoAOMT, F5H, and COMT were maintained at a low level or down-regulated to inhibit the conversion to the typical G and S lignin. Quantitative real-time RT-PCR analysis confirmed the altered expression levels of these genes in seeds and vegetative tissues. Conclusions This work demonstrated the plasticity of natural lignin polymer assembly in seed and provided a better understanding of the molecular mechanism of seed-specific lignification process.

Abstract Background Clerodendrum inerme (L.) Gaertn, a halophyte, usually grows on coastal beaches as an important mangrove plant. The salt-tolerant mechanisms and related genes of this species that respond to short-term salinity stress are unknown for us. The de novo transcriptome of C. inerme roots was analyzed using next-generation sequencing technology to identify genes involved in salt tolerance and to better understand the response mechanisms of C. inerme to salt stress. Results Illumina RNA-sequencing was performed on root samples treated with 400 mM NaCl for 0 h, 6 h, 24 h, and 72 h to investigate changes in C. inerme in response to salt stress. The de novo assembly identified 98,968 unigenes. Among these unigenes, 46,085 unigenes were annotated in the NCBI non-redundant protein sequences (NR) database, 34,756 sequences in the Swiss-Prot database and 43,113 unigenes in the evolutionary genealogy of genes: Non-supervised Orthologous Groups (eggNOG) database. 52 Gene Ontology (GO) terms and 31 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were matched to those unigenes. Most differentially expressed genes (DEGs) related to the GO terms “single-organism process”, “membrane” and “catalytic activity” were significantly enriched while numerous DEGs related to the plant hormone signal transduction pathway were also significantly enriched. The detection of relative expression levels of 9 candidate DEGs by qRT-PCR were basically consistent with fold changes in RNA sequencing analysis, demonstrating that transcriptome data can accurately reflect the response of C. inerme roots to salt stress. Conclusions This work revealed that the response of C. inerme roots to saline condition included significant alteration in response of the genes related to plant hormone signaling. Besides, our findings provide numerous salt-tolerant genes for further research to improve the salt tolerance of functional plants and will enhance research on salt-tolerant mechanisms of halophytes.

Worldwide, there has been an exponential growth in the production and application of lithium-ion batteries (LIBs), driven by the energy transition and the electric vehicle market. The scarcity of raw materials and the circular economy strategy of LIBs encourage the need to reuse components, recycle, and give second life to used batteries. However, one of the obstacles is the insufficient volume of LIBs for recycling, which prevents the economic viability of this industrial process. Thus, this article mainly focuses on the economic aspects of the recycling of LIBs, presenting and analyzing: (i) the advantages and disadvantages of recycling and (ii) a survey of factors that influence the cost and economic feasibility of disposing of batteries. The importance of regulations, the market, and business models regarding the recycling of LIBs in a few countries are also discussed. Finally, a business model is created for recycling LIBs in Brazil. The main factors that influence the economic feasibility of this process are indicated, such as government incentives through regulation, exemption from fees and taxes, and the adequacy of battery technology. Encouraging recycling through tax exemptions or reductions can make the process more economically viable, in addition to contributing to the circular economy. Another essential factor to be considered is the creation of joint ventures, which can facilitate the entire chain of the circular economy, including logistics, transport, and disposal of batteries.

Raw lacquer (RL) is a natural polymer compound with highly promising applications; however, its inflammable attribute restricts the industrial applications. In this study, melamine is used to formulate tri (1-melamine-2-propanol) phosphate (FR-1), after which it is synthesized with ammonium phosphate (FR-2) and diatomite to form a compound phosphorus-nitrogen intumescent flame retardant (IFR). Next, IFR is used as the filling agent that then cross-links with RL, and as such RL/IFR membranes are formed after the curing. The limiting oxygen index (LOI) measurement, the vertical combustion test (UL-94), the microshape calorimetric analysis (CCT), and the thermal gravimetric analysis (TGA) are conducted to examine the combustion resistance and thermal stability of the membranes. Fourier transform infrared spectroscopy (FT-IR) and electron scanning microscope (SEM) are performed to separately characterize the structure and compatibility; the mechanical properties of the membranes are also evaluated. The vertical combustion test results confirm that with 30 wt% of IFR, RL/IFR membranes acquire 12.3% higher LOI and a vertically combustion of V-0 level. The TGA indicates that RL/IFR membranes demonstrate a greater adhesion level, a higher rigidity, and better luster than pure RL membranes.

Different amounts of urushiol were added to a fixed amount of polyacrylonitrile (PAN) to make nanoscale urushiol/PAN films by the electrospinning method. Electrospinning solutions were prepared by using dimethylformamide (DMF) as the solvent. Nanoscale urushiol/PAN films and conductive Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)/polyvinyl pyrrolidone (PVP) films were prepared by electrospinning. In order to prepare an electrospun sandwich nanoscale film, urushiol/PAN films were deposited as both the top and bottom layers and PEDOT:PSS/PVP film as the inner layer. When the PAN to urushiol ratio was 7:5, the fiber diameter ranged between 150 nm and 200 nm. The single-layer urushiol/PAN film could not be etched after being immersed into 60%, 80%, and 100% sulfuric acid (H2SO4) for 30 min, which indicated the improved acid resistance of the PAN film. The urushiol/PAN film was used to fabricate the sandwich nanoscale films. When the sandwich film was immersed into 80% and 100% H2SO4 solutions for 30 min, the structure remained intact, and the conductive PVP film retained its original properties. Thus, the working environment tolerability of the functional PVP film was increased.

Filamentous temperature-sensitive protein Z (Tubulin/FtsZ) family is a group of conserved GTP-binding (guanine nucleotide-binding) proteins, which are closely related to plant tissue development and organ formation as the major component of the cytoskeleton. According to the published genome sequence information of cassava (Manihot esculenta Crantz), 23 tubulin genes (MeTubulins) were identified, which were divided into four main groups based on their type and phylogenetic characteristics. The same grouping generally has the same or similar motif composition and exon–intron structure. Collinear analysis showed that fragment repetition event is the main factor in amplification of cassava tubulin superfamily gene. The expression profiles of MeTubulin genes in various tissue were analyzed, and it was found that MeTubulins were mainly expressed in leaf, petiole, and stem, while FtsZ2-1 was highly expressed in storage root. The qRT-PCR results of the FtsZ2-1 gene under hormone and abiotic stresses showed that indole-3-acetic acid (IAA) and gibberellin A3 (GA3) stresses could significantly increase the expression of the FtsZ2-1 gene, thereby revealing the potential role of FtsZ2-1 in IAA and GA3 stress-induced responses.

Raw lacquer (RL), ethanol being used as the solvent, was added to polyvinyl pyrrolidone (PVP) and then electrospun into RL/PVP nanofilms. Manufacturing parameters such as RL/PVP ratio, voltage, flow velocity, needle type, and the distance between syringe and the collection board were systematically investigated. A scanning electronic microscope (SEM) was used to observe the surface morphology of nanofilms; the block drop method was used to measure the water contact angle; the mechanical properties of RL/PVP nanofilms of different proportions were tested by universal material testing machine; and Fourier-transform infrared spectroscopy (FT-IR) was used to characterize the structure. Based on the water resistance and acid resistance measurements, the proposed nanofilms demonstrated to be water and acid resistant were successfully produced. The results show that PVP that melts in water becomes incompatible with water after adding raw lacquer, and the acid resistance is greatly improved. Furthermore, the smaller the fiber diameter, the better the mechanical properties of the nanofilms are under low ratio of RL/PVP. With a high proportion of RL/PVP, the inner structure of the nanofilm is denser, and the water resistance and acid resistance are better. The dense structure can protect the inner material of the nanofilms.

Space particle irradiation produces ionization damage and displacement damage in semiconductor devices. The enhanced low dose rate sensitivity (ELDRS) effect caused by ionization damage has attracted wide attention. However, the enhanced low-particle-flux sensitivity effect and its induction mechanism by displacement damage are controversial. In this paper, the enhanced low-neutron-flux sensitivity (ELNFS) effect in Boron-doped silicon and the relationship between the ELNFS effect and doping concentration are further explored. Boron-doped silicon is sensitive to neutron flux and ELNFS effect could be greatly reduced by increasing the doping concentration in the flux range of 5 × 109–5 × 1010 n cm−2 s−1. The simulation based on the theory of diffusion-limited reactions indicated that the ELNFS in boron-doped silicon might be caused by the difference in the concentration of remaining vacancy-related defects (Vr) under different neutron fluxes. The ELNFS effect in silicon becomes obvious when the (Vr) is close to the boron doping concentration and decreased with the increase in boron doping concentration due to the remaining vacancy-related defects being covered. These conclusions are confirmed by the p+-n-p Si-based bipolar transistors since the ELNFS effect in the low doping silicon increased the reverse leakage of the bipolar transistors and the common-emitter current gain (β) dominated by highly doped silicon remained unchanged with the decrease in the neutron flux. Our work demonstrates that the ELNFS effect in boron-doped silicon can be well explained by noise diagnostic analysis together with electrical methods and simulation, which thus provide the basis for detecting the enhanced low-particle-flux damage effect in other semiconductor materials.

Background Death-associated protein kinase 1 (DAPK) is an important tumor suppressor kinase involved in the regulation of multiple cellular activities such as apoptosis and autophagy. DNA methylation of DAPK gene was found in various types of cancers and often correlated with the clinicopathological characteristics. However, the mRNA and protein expression of DAPK in the same sample was rarely measured. Thus, it was unclear if the correlation between DAPK gene methylation and clinicopathological parameters was due to the loss of DAPK expression. Methods In this study, the DNA methylation rate, mRNA and protein expression of DAPK was quantitatively detected in 15 pairs of breast cancer patient samples including tumor (T) and adjacent non-tumor (N) tissues. Results The correlation between DNA methylation rate and mRNA expression, together with the correlation between mRNA and protein expression, was calculated. No correlation was observed between any levels using either the measurement value of each sample or the T/N ratio of each pair. Discussion These data suggested that the DNA methylation status of DAPK did not correlate well with its mRNA or protein expression. Extra caution is needed when interpreting the DNA methylation data of DAPK gene in clinical studies.

Renanthera imschootiana Rolfe is an endangered tropical epiphytic orchid that is threatened with extinction due to over-collection and the loss of suitable habitats. In vitro propagation is a useful way to mass produce plants for re-establishment in the wild and for commercial propagation. Seeds collected 150 days after pollination (DAP) were the optimum stage for in vitro culture. Seed germination reached 93.1% on quarter-strength MS (i.e., MS containing a quarter of macro- and micronutrients) medium containing 0.5 mg l(-1) α-naphthaleneacetic acid (NAA), 20% coconut water (CW), 1.0 g l(-1) peptone, 10 g l(-1) sucrose and 1.0 g l(-1) activated charcoal (AC). Quarter-strength MS medium supplemented with 1.0 mg l(-1) BA, 0.5 mg l(-1) NAA, 1.0 g l(-1) peptone, 10 g l(-1) sucrose and 20% CW was suitable for the sub-culture of protocorm-like bodies (PLBs) in which the PLB proliferation ratio was 2.88. Quarter-strength MS medium containing 1.0 mg l(-1) NAA, 1.0 g l(-1) peptone, 100 g l(-1) banana homogenate (BH), and 1.0 g l(-1) AC was suitable for plantlet formation and 95.67% of plantlets developed from PLBs within 60 days of culture. Hyponex N016 medium supplemented with 0.5 mg l(-1) NAA, 1.0 g l(-1) peptone, 20 g l(-1) sucrose, 150 g l(-1) BH, and 1.0 g l(-1) AC was suitable for the in vitro growth of plantlets about 2-cm in height. Plantlets 3-cm in height or taller were transplanted to Chilean sphagnum moss, and 95% of plantlets survived after 60 days in a greenhouse. Three hundred transplanted of seedlings 360-days old were reintroduced into three natural habitats. Highest percentage survival (79.67%) was observed in Yuanjiang Nature Reserve two years after reintroduction, followed by Huolu Mountain forest park (71.33%). This protocol is an efficient means for the large-scale propagation and in vitro and in vivo germplasm conservation of R. imschootiana.

Lattice metamaterials have demonstrated remarkable mechanical properties at low densities. As these architected materials advance toward real-world applications, their tolerance for damage and defects becomes a limiting factor. However, a thorough understanding of the fracture resistance and fracture mechanisms in lattice metamaterials, particularly for the emerging shell-based lattices, has remained elusive. Here, using a combination of in situ fracture experiments and finite element simulations, we show that shell-based lattice metamaterials with Schwarz P minimal surface topology exhibit superior fracture resistance compared to conventional octet truss lattices, with average improvements in initiation toughness up to 150%. This superiority is attributed to the unique shell-based architecture that enables more efficient load transfer and higher energy dissipation through material damage, structural plasticity, and material plasticity. Our study reveals a topology-induced intrinsic toughening mechanism in shell-based lattices and highlights these architectures as a superior design route for creating lightweight and high-performance mechanical metamaterials. [ABSTRACT FROM AUTHOR]