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LATERAL ORGAN BOUNDARIES DOMAIN (LBD) genes encode plant-specific transcription factors that participate in regulating various developmental processes. In this study, we genetically characterized PagLBD3 encoding an important regulator of secondary growth in poplar (Populus alba × Populus glandulosa). Overexpression of PagLBD3 increased stem secondary growth in Populus with a significantly higher rate of cambial cell differentiation into phloem, while dominant repression of PagLBD3 significantly decreased the rate of cambial cell differentiation into phloem. Furthermore, we identified 1756 PagLBD3 genome-wide putative direct target genes (DTGs) through RNA sequencing (RNA-seq)-coupled DNA affinity purification followed by sequencing (DAP-seq) assays. Gene Ontology analysis revealed that genes regulated by PagLBD3 were enriched in biological pathways regulating meristem development, xylem development, and auxin transport. Several central regulator genes for vascular development, including PHLOEM INTERCALATED WITH XYLEM (PXY), WUSCHEL RELATED HOMEOBOX4 (WOX4), Secondary Wall-Associated NAC Domain 1s (SND1-B2), and Vascular-Related NAC-Domain 6s (VND6-B1), were identified as PagLBD3 DTGs. Together, our results indicate that PagLBD3 and its DTGs form a complex transcriptional network to modulate cambium activity and phloem/xylem differentiation.

Starch is the most important component in endosperm of sorghum grain. Usually, two types of starch are present: amylose (AM) and amylopectin (AP). The levels of AM and AP contents play a significant role in the appearance, structure, and quality of sorghum grains and in marketing applications. In the present study, a panel of 634 sorghum (Sorghum bicolor (L.) Moench) accessions were evaluated for starch, AM, and AP contents of grain, which included a mini core collection of 242 accessions from the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in India, and 252 landraces and 140 cultivars from China. The average starch content was 67.64% and the average AM and AP contents were 20.19 and 79.81%, respectively. We developed a total of 260 000 high-confidence single nucleotide polymorphism (SNP) markers in the panel of 634 accessions of S. bicolor using specific locus amplified fragment sequencing (SLAF-seq). We performed genome-wide association studies (GWAS) of starch, AM, and AM/AP of grain and SNP markers based on a mixed linear model (MLM). In total, 70 significant association signals were detected for starch, AM, and AM/AP ratio of grain with P

Objective Invasive pulmonary Aspergillus infection has the characteristics of high morbidity, difficult to be treated, poor prognosis and high mortality. This study aims to investigate the effects of cinnamaldehyde on 1,3-β- D -glucans in the pulmonary Aspergillus fumigatus cell wall to provide a basis for developing novel antifungal drugs. Methods Immunosuppressed ICR mice were intranasally inoculated with 50 µL of A. fumigatus suspension (1 × 107 CFU/mL) and then separated into two groups, for the experimental group cinnamaldehyde was orally administered at 240 mg/kg/d consecutively for 14 d. While for the control group, voriconazole was used to treat the fungus infection. Pulmonary tissues were then extracted for 1,3-β- D -glucans assay and electron microscopy. Results The concentration of 1,3-β- D -glucans was significantly different between the cinnamaldehyde and voriconazole groups, which was (1160.89 ± 364.96) pg/mL and (3885.94 ± 845.45) pg/mL, respectively (P D -glucan layer) of A. fumigatus cell wall were damaged and fell off, resulting in serious defect of the cell wall, but the cell membrane was clear and intact. Conclusion Cinnamaldehyde has a significant influence on the integrity of 1,3-β- D -glucans in the pulmonary A. fumigatus cell wall, but the cell membrane is unaffected, suggesting that cinnamaldehyde has unique antifungal properties depending on its action against the 1,3-β- D -glucans on the pulmonary A. fumigatus cell wall.

Sugar metabolism is the most important and core one which drives plant growth and development. Invertases are key enzymes that regulate sugar metabolism. A still-growing number of studies have revealed that invertases play a crucial role in various aspects of plant growth and development. Crop yield is the product of sugar metabolism; it could be deduced that invertase also regulated the yield formation. So we have done a series of research on soluble acid invertase in sweet sorghum from enzyme activity to gene cloning and functional marker development. In this paper, we sequenced full length of SAI-1 gene in 69 grain sorghum parent lines, trying to see how it differs in their gene sequences and their distribution in related hybrid varieties released in the past. To our surprise, the result showed that B-lines and restore lines (R-line) have almost different SAI-1 haplotype distribution. The change of haplotype of SAI-1 gene is associated with yield gain as with grain sorghum breeding progress, which proved that SAI-1 may take a very important role in yield formation. And we also found the SAI-1 gene tends to become shorter as with the breeding advance, which means short sequence in introns, while exon remains unchanged leading to higher gene efficiency. The best SAI-1 haplotype combination of sorghum hybrid was also found for different planting regions. These findings are of great significance for improving breeding efficiency, understanding heterosis, and germplasm enhancement. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11032-021-01231-2.

Aeromonas hydrophila is an important pathogen that causes motile Aeromonas septicemia (MAS) in the aquaculture industry. Aerolysin, hemolysin, serine protease and enterotoxins are considered to be the major virulence factors of A. hydrophila. In this study, we constructed a five-gene (aerA, hly, ahp, alt and ast) deletion mutant strain (named Aeromonas hydrophila five-gene deletion strain, AHFGDS) to observe the biological characteristics and detect its potential as a live-attenuated vaccine candidate. AHFGDS displayed highly attenuated and showed increased susceptibility to fish blood and skin mucus killing, while the wild-type strain ZYAH72 was highly virulent. In zebrafish (Danio rerio), AHFGDS showed a 240-fold higher 50% lethal dose (LD50) than that of the wild-type strain. Immunization with AHFGDS by intracelomic injection or immersion routes both provided grass carp (Ctenopharyngodon idella) significant protection against the challenge of the strain ZYAH72 or J-1 and protected the fish organs from serious injury. Further agglutinating antibody titer test supported that AHFGDS could elicit a host-adaptive immune response. These results suggested the potential of AHFGDS to serve as a live-attenuated vaccine to control A. hydrophila infection in aquaculture.

Objective Invasive pulmonary candidiasis is a disease with high incidence, difficult treatment, poor prognosis, and high mortality. The present study analyzed the influence of cinnamaldehyde on 1,3-β-D-glucans in the cell wall of Candida albicans in order to provide a theoretical basis for the research of antifungal drugs. Methods An immunosuppressed BALB/c mouse model with invasive pulmonary candidiasis was established by nasal perfusion of 50 µL of C. albicans suspension (107 cfu/mL). 1,3-β-D-glucans examination and electron microscopy were carried out. Fluconazole was used as the control. Results Cinnamaldehyde was administered at a dose of 240 mg/kg/d for 14 consecutive days, and the measured value of 1,3-β-D-glucans was (1160.62 ± 89.65) pg/mL, whereas that of fluconazole was (4285.87 ± 215.62) pg/mL. The difference between the two groups was statistically significant (P Conclusion Cinnamaldehyde demonstrated special efficacy on 1,3-β-D-glucans in the cell wall of C. albicans.

We aimed to construct a highly efficient, lentivirus-mediated vector for RNA interference (RNAi) silencing of the Id1 gene and to examine whether silencing of this gene promotes the neural differentiation of mesenchymal stem cells (MSCs). Three short hairpin RNA sequences targeting the coding region of the Id1 gene and one negative control (NC) sequence were designed. After monophosphorylation, these sequences were introduced into lentiviral vectors containing enhanced green fluorescent protein (EGFP) using the restriction enzyme BsmBI to construct the recombinant vectors pWSLV-EGF-shId1 (1-3) and pWSLV-EGF-NC. These recombinant lentivirus vectors were transfected into H9C2 cells to assess the silencing effect of the shId1 (1-3) sequences on the Id1 gene. Subsequently, pWSLV-EGF-NC and pWSLV-EGF-shId1 which exhibited the strongest silencing effect were transfected into the packaging cell line 293 FT. After determining the viral titers, the cultured MSCs were infected with the lentivirus (multiplicity of infection, MOI = 10). Real-time polymerase chain reaction (PCR) and Western blotting were used to examine the amounts of Id1 mRNA and protein, respectively, in the transfected MSCs, and the results revealed that Id1 expression was markedly inhibited. Finally, MSCs were treated with the growth factors EGF and bFGF in conjunction with ligustrazine to induce their differentiation into neuron-like cells. The expression of NSE/MAP-2/Nestin was detected using immunocytochemistry and real-time PCR, which revealed that the rate of neural differentiation in the pWSLV-EGF-shId1 group was higher than that of the other groups, as was NSE/MAP-2 expression. Thus, Id1 gene silencing promotes the neural differentiation of MSCs.

Aeromonas hydrophila is a pathogen that causes high mortality in the grass carp. The complement system, as a frontline defence of innate immunity, plays an important role in the immune response against pathogens. However, the immunity evasion mechanism of A. hydrophila against the complement system of grass carp remains unclear. In this study, we described an additional mechanism used by A. hydrophila GD18 to evade the complement system and survive in grass carp serum. First, A. hydrophila evaded the bactericidal activity of grass carp serum. Second, the haemolytic activity assays showed that A. hydrophila obviously suppressed the alternative pathway, which depended on preventing the formation or disabling the function of the membrane-attack complex (MAC). Further research indicated that A. hydrophila targeted complement C3, the central component of the three complement pathways, and degraded it in the grass carp serum, leading to the inhibition of the complement pathways, which resulted in the serum-resistance of A. hydrophila. Furthermore, cleavage analyses showed that extracellular proteases (ECPases) of A. hydrophila efficiently cleaved purified C3 as well as C3 in grass carp serum. Finally, protease inhibitor studies and mass spectrum analysis identified the secreted metalloprotease elastase (AhE), which was present in large amounts in crude ECPases, as the central molecule responsible for C3 cleavage. Compared to wild strain GD18, the AhE knockout, Δahe was dramatically reduced in the ability of serum resistance. Our findings suggested that A. hydrophila escaped serum-killing by suppressing the complement pathways via the degradation of complement C3 in bony fish, which was related to secreted metalloproteases.

To evaluate the effect and safety of cinnamaldehyde on immunosuppressed mice with invasive pulmonary candidiasis. An immunosuppressed BALB/c mouse model was established by intraperitoneal administration of cyclophosphamide (200 mg/kg) once daily for 2 days. The immunosuppressed mouse with invasive pulmonary candidiasis model was further established by nasal perfusion of Candida albicans suspension. In the cinnamaldehyde treatment group, immunosuppressed mice with invasive pulmonary candidiasis were orally given cinnamaldehyde 240 mg/(kg·d) for 14 consecutive days. Fluconazole and 0.9% saline were used as the positive and negative controls, respectively. The mice in the cinnamaldehyde safety evaluation group were orally administered cinnamaldehyde 480 mg/(kg·d) for 42 days to observe the safety of the drug. Microscopic identification, fungal culture, histopathological examination, and (1,3)-beta-D-glucans detection were conducted to analyze the effect of cinnamaldehyde on C. albicans. The fungal clearance rate in the cinnamaldehyde treatment group was higher than that in the fluconazole control group (80.00% vs. 56.67%, P

Background.The invasive pulmonary aspergillosis is a kind of high incidence of disease with difficulties in treatment, poor prognosis, and high mortality.Objectives.The study aimed to reveal the effect of cinnamaldehyde on the fungal cell wall and verify its efficacy on invasive pulmonary aspergillosis on immunosuppressed Institute of Cancer Research mice (ICR mice).Methods.ICR mice were given cyclophosphamide 200 mg.kg−1. d−1by intraperitoneal injection for 2 days. On the 4th day, the mice were given 50μLofAspergillosis fumigatusspore (107colony form unit CFU/mL) by intranasal injection to establish immunosuppressive animal models with invasiveAspergillosis fumigatusinfection. Then the mice in treatment group orally administered cinnamaldehyde for 14 consecutive days, while voriconazole was given to the mice in the positive control group.Results.The clearance rate of pulmonary fungi, cure rate, and reduction of 1,3-β-D-glucans in treatment group were 80.00%, 80.00%, and 81.00%, respectively while in positive control group they were 67.00%, 60.00%, and 62.00%, respectively. There were significant differences in the results between two groups as mentioned above (PAspergillus fumigatuswas dissolved and detached and the cell surface was incomplete. There were edema, degeneration, and necrosis in nucleus and organelle, which lead to cellular necrocytosis. The cytomembrane ofAspergillus fumigatuswas intact, clear, and complete, whereas the cytomembrane in the positive control group disappeared. The hyphal morphology ofAspergillus fumigatuswas deformed, but the cell wall was intact.Conclusion.Cinnamaldehyde has a good curative effect in the treatment of invasive pulmonary aspergillus infection in immunodeficient mice. It mainly affects the synthesis of 1,3-β-D-glucans from the cytoderm ofAspergillus fumigatusbut does not affect cell wall. It would potentially be an effective and novel drug for targeted treatment ofAspergillus fumigatusdeep infection.

Oxidative stress and inflammation are hypothesized to contribute to the pathogenesis of chronic obstructive pulmonary disease (COPD). Resveratrol (trans-3,5,4′-trihydroxystilbene) is known for its antioxidant and anti-inflammatory properties. The study aimed to investigate the effects of resveratrol in a rat model with COPD on the regulation of oxidative stress and inflammation via the activation of Sirtuin1 (SIRTl) and proliferator-activated receptor-γ coactivator-1α (PGC-1α). Thirty Wistar rats were randomly divided into three groups: control group, COPD group and resveratrol intervention group. The COPD model was established by instilling with lipopolysaccharide (LPS) and challenging with cigarette smoke (CS). The levels of interleukin-6 (IL-6) and interleukin-8 (IL-8) in serum were measured. The levels of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were measured. The expression levels of SIRT1 and PGC-1α in the lung tissues were examined by immunohistochemistry as well as real-time reverse transcriptase polymerase chain reaction (real-time RT-PCR) and western blotting analysis. After the treatment with resveratrol (50 mg/kg), compared with the COPD group, alleviation of inflammation and reconstruction in the small airways of the lungs were seen. Resveratrol might be correlated not only with the lower level of MDA and the higher activity of SOD, but also with the upregulation of SIRT1 and PGC-1α expression. Resveratrol treatment decreased serum levels of IL-6 and IL-8. Our findings indicate that resveratrol had a therapeutic effect in our rat COPD model, which is related to the inhibition of oxidative stress and inflammatory response. The mechanism may be related to the activation and upgrading of the SIRT1/PGC-1α signaling pathways. Thus resveratrol might be a therapeutic modality in COPD.

A molecular analysis was performed on 56 taxa in the orchid genus Cypripedium using nrDNA ITS and five chloroplast regions (trnH-psbA, atpI-atpH, trnS-trnfM, trnL-F spacer, and the trnL intron). The genus Cypripedium was confirmed as monophyletic. Our data provided strong support for monophyletic grouping of eight infrageneric sections (Subtropica, Obtusipetala, Trigonopedia, Sinopedilum, Bifolia, Flabelinervia, Arietinum, and Cypripedium) defined in earlier taxonomic treatments, and paraphyletic grouping of two sections (Irapeana and Retinervi). Within the genus Cypripedium, the first divergent lineage consisted of two Mesomaerican species, and subsequently the Cypripedium debile lineage from eastern Asia was split. Our study did not support the notion that two Asian species (Cypripedium subtropicum and Cypripedium singchii) were closely related to either Mesoamerican Cypripedium irapeanum or North American Cypripedium californicum, as indicated by previous interpretations based on morphological evidences. In addition, one pair of vicariant species, Cypripedium plectrochilum (eastern Asia) and Cypripedium arietinum (North America), unique to section Arietinum, was confirmed. Furthermore, within the monophyletic section Cypripedium two previously recognized subsections, Cypripedium and Macrantha, were shown to be paraphyletic. Our results suggested that this section split into two groups based on distribution (North America vs. Eurasia) instead of such previously used, morphological traits as flower color, and the shape of the lips (labellum) and lateral petals.

A total of 98 non-symbiotic endophytic bacterial strains isolated from soybean root nodules were classified into eight rDNA types in ARDRA analysis and 21 BOX types in BOX-PCR. The phylogenetic analysis of 16S rDNA identified these strains as Pantoea, Serratia, Acinetobacter, Bacillus, Agrobacterium, and Burkholderia. Limited genetic diversity was revealed among these bacteria since most of the strains (85.7%) were found in three very similar rDNA types corresponding to Pantoea agglomerans, and many strains shared the same BOX-PCR patterns. The inoculation of nodule endophytes had no significant effects on the growth and nodulation of soybean, but most of the strains produced indoleacetic acid (IAA), could solubilize mineral phosphate, and could fix nitrogen, implying that they are a valuable pool for discovering plant growth promoting bacteria. Our results demonstrated that the nodule endophytes were common in soybean and their diversity was affected by the plant's character and the soil conditions. The 99% similarities found in the nifH genes of Bradyrhizobium japonicum and of the endophytic Bacillus strains strongly indicated that horizontal transfer of symbiotic genes happened between the symbiotic bacteria and the endophytes.

In maize, three isoforms of starch-branching enzyme, SBEI, SBEIIa, and SBEIIb, are encoded by the Sbe1a, Sbe2a, and Amylose extender (Ae) genes, respectively. The objective of this research was to explore the effects of null mutations in the Sbe1a and Ae genes alone and in combination in wx background on kernel characteristics and on the morphology and physical behavior of endosperm starch granules. Differences in kernel morphology and weight, starch accumulation, starch granule size and size distribution, starch microstructure, and thermal properties were observed between the ae wx and sbe1a ae wx plants but not between the sbe1a wx mutants when compared to wx. Starch from sbe1a ae wx plants exhibited a larger granule size with a wider gelatinization temperature range and a lower endotherm enthalpy than ae wx. Microscopy shows weaker iodine staining in sbe1a ae wx starch granules. X-ray diffraction revealed A-type crystallinity in wx and sbe1a wx starches and B-type in sbe1a ae wx and ae wx. This study suggests that, while the SBEIIb isoform plays a dominant role in maize endosperm starch synthesis, SBEI also plays a role, which is only observable in the presence of the ae mutation.

The recently published crystal structure of the external domains of alphaVbeta3 confirms the prediction that the aminoterminal portion of alphaV, which shares 40% homology with alphaIIb, folds into a beta-propeller structure and that the 4 calcium-binding domains are positioned on the bottom of the propeller. To gain insight into the role of the calcium-binding domains in alphaIIb biogenesis, we characterized mutations in the second and third calcium-binding domains of alphaIIb in 2 patients with Glanzmann thrombasthenia. One patient inherited a Val298Phe mutation in the second domain, and the other patient inherited an Ile374Thr mutation in the third domain. Mammalian cell expression studies were performed with normal and mutant alphaIIb and beta3 cDNA constructs. By flow cytometry, expression of alphaIIb Val298Phe/beta3 in transfected cells was 28% of control, and expression of alphaIIbIle374Thr/beta3 was 11% of control. Pulse-chase analyses showed that both mutant pro-alphaIIb subunits are retained in the endoplasmic reticulum and degraded. Mutagenesis studies of the Val298 and Ile374 residues showed that these highly conserved, branch-chained hydrophobic residues are essential at these positions and that biogenesis and expression of alphaIIbbeta3 is dramatically affected by structural variations in these regions of the calcium-binding domains. Energy calculations derived from a new model of the alphaIIb beta-propeller indicate that these mutations interfere with calcium binding. These data suggest that the alphaIIb calcium-binding domains play a key structural role in the beta-propeller, and that the structural integrity of the calcium-binding domains is critical for integrin biogenesis.

Seasonal alteration of the cytosolic and nuclear Ca2+ concentrations of spruce (Picea engelmannii Parry) and brome grass (Bromus inermis Leyss) was investigated by the antimonate precipitation cytochemical technique. Electron microscopic (EM) observations revealed that electron-dense Ca2+ antimonate deposits, an indication of Ca2+ localization, were seen mainly in the vacuole, the cell wall and the intercellular space in samples of both species, collected on 14 July 1997. Few deposits were found in the cytosol and nuclei, showing a low resting level during summer months. On 8 Aug. 1997 following a decrease in daylength of 1 hour and 12 minutes, Ca2+ accumulation was initiated in spruce with increased cytosolic and nuclear Ca2+ deposits, but not in brome grass. On 8 Sept. 1997, Ca2+ accumulation occurred in the cytosol of brome grass. This followed a drop in ambient temperature to 12 °C. Cytosolic and nuclear Ca2+ deposits continued to increase in spruce. Controlled experiments confirmed that it was the low temperature, not shortening daylength, that triggered Ca2+ accumulation in brome grass. High cytosolic and nuclear Ca2+ concentrations lasted about three months in spruce from early August to early November. However, the high cytosolic and nuclear Ca2+ concentrations in brome grass lasted only about 20 days from early September to the end of the month. During winter and spring, both species had low resting cytosolic and nuclear Ca2+ concentrations. The relationship between the duration of the high cytosolic and nuclear Ca2+ concentrations and the status of the developed dormancy/cold hardiness is discussed in light of current findings.

Electron microscopic observations revealed that electron-dense antimonate Ca2+ deposits were mostly localized in the vacuole and the intercellular space in both maize and winter wheat when their seedlings were grown at 25 degrees C. The reaction products--cerium phosphate deposits of Ca2+ -ATPase activity were mainly seen at the cytoplasmic side of the plasma membrane. Few cerium phosphate deposits also were observed on the nuclear envelope. In both species, after 1 or 3 h 2 degrees C chilling, antimonate Ca2+ deposits increased in the cytosol and the nucleus, but cerium phosphate deposits showed no visible difference compared to their corresponding 25 degrees C seedlings. After 12, 24, or 72 h chilling, maize seedlings still maintained a high level of antimonate Ca2+ deposits in the cytosol and the nucleus. During these periods, maize Ca2+ -ATPase, as indicated by the number of cerium phosphate deposits, became less and less active as chilling proceeded. In winter wheat, the increased cytosolic and nuclear antimonate Ca2+ deposits were restored to a low resting level after 12, 24, or 72 h chilling, while the Ca2+ -ATPase was maintained active, contrary to maize scenario. The transient cytosolic and nuclear Ca2+ increase and the activities of Ca2+ -ATPase during chilling are discussed in relation to plant chilling injury and cold acclimation.

Subcellular localization of calcium in apical bud cells of mulberry (Morus bombciz Koidz) was investigated by a combination of calcium antimonate precipitation and electron microscopy (EM), over a 10-month period extending from July to May. Calcium antimonate deposits, an indication of Ca 2+ localization, were found mainly in the intercellular spaces and vacuoles of tissues collected in summer (e.g., July 10). Few deposits were seen in the cytosol and the nucleus, indicating that when plants were actively growing, the cytoplasm had a low concentration of Ca 2+ . As the day length became shorter (e.g., August 8), Ca 2+ deposits increased in the cytosol and the nucleus. When plant dormancy and cold hardiness were rapidly developing in September and October, a large number of Ca 2+ deposits were seen in the cytoplasm and the nucleus, where they remained for about 60 days. Tissue samples collected during midwinter (e.g., January 20) displayed few Ca 2+ deposits in the cytoplasm and the nucleus compared with the sample collected on November 1. The number of Ca 2+ deposits remained low even when day length increased in the spring (e.g., May 5). We conclude that the seasonal dynamics of intracellular Ca 2+ concentration bear a close relationship with growth cessation and the development of dormancy and cold hardiness in temperate woody perennials.

Plasma membrane (PM) Ca2+-ATPase activity in poplar apical bud meristematic cells during short-day (SD)-induced dormancy development was examined by a cerium precipitation EM-cytochemical method. Ca2+-ATPase activity, indicated by the status of cerium phosphate precipitated grains, was localized mainly on the interior face (cytoplasmic side) of the PM when plants were grown under long days and reached a deep dormancy. A few reaction products were also observed on the nuclear envelope. When plant buds were developing dormancy after 28 to 42 d of SD exposure, almost no reaction products were present on the interior face of the PM. In contrast, a large number of cerium phosphate precipitated grains were distributed on the exterior face of the PM. After 70 d of SD exposure, when buds had developed a deep dormancy, the reaction products of Ca2+-ATPase activity again appeared on the interior face of the PM. The results seemed suggesting that two kinds of Ca2+-ATPases may be present on the PM during the SD-induced dormancy in poplar. One is the Ca2+-pumping ATPase, which is located on the interior face of the PM, for maintaining and restoring the Ca2+ homeostasis. The other might be an ecto-Ca2+-ATPase, which is located on the exterior face of the PM, for the exocytosis of cell wall materials as suggested by the fact of the cell wall thickening during the dormancy development in poplar.