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In flowering plants, stamen development is a complex multistage process, which is highly regulated by a series of transcription factors. In this study, BcMF28 , which encodes a R2R3-MYB transcription factor, was isolated from Brassica campestris. BcMF28 is localized in the nucleus and cytoplasm, and acts as a transcriptional activator. Quantitative real-time PCR and promoter activity analysis revealed that BcMF28 was predominately expressed in inflorescences. The expression of BcMF28 was specifically detected in tapetum, developing microspores, anther endothecium, and filaments during late stamen development. The overexpression of BcMF28 in Arabidopsis resulted in aberrant stamen development, including filament shortening, anther indehiscence, and pollen abortion. Detailed analysis of anther development in transgenic plants revealed that the degeneration of septum and stomium did not occur, and endothecium lignification was affected. Furthermore, the expression levels of genes involved in the phenylpropanoid metabolism pathway were altered in BcMF28 -overexpressing transgenic plants. Our results suggest that BcMF28 plays an important regulatory role during late stamen development. • BcMF28 encodes a R2R3-MYB transcriptional activator. • BcMF28 is predominantly expressed in inflorescences, especially in tapetum, microspores, anther endothecium and filaments. • BcMF28 overexpressing in Arabidopsis caused filament shortening, anther indehiscence, and pollen abortion.aberrant pollens, shorter filaments, and non-dehiscent anthers. • BcMF28 overexpressing in Arabidopsis altered gene expression involved in the phenylpropanoid metabolism pathway. [ABSTRACT FROM AUTHOR]

Background: Genic male sterility (GMS) line is an important approach to utilize heterosis in Brassica rapa, one of the most widely cultivated vegetable crops in Northeast Asia. However, the molecular genetic mechanisms of GMS remain to be largely unknown. Results: Detailed phenotypic observation of 'Bcajh97-01A/B', a B. rapa genic male sterile AB line in this study revealed that the aberrant meiotic cytokinesis and premature tapetal programmed cell death occurring in the sterile line ultimately resulted in microspore degeneration and pollen wall defect. Further gene expression profile of the sterile and fertile floral buds of 'Bcajh97-01A/B' at five typical developmental stages during pollen development supported the result of phenotypic observation and identified stage-specific genes associated with the main events associated with pollen wall development, including tapetum development or functioning, callose metabolism, pollen exine formation and cell wall modification. Additionally, by using ChIP-sequencing, the genomic and gene-level distribution of trimethylated histone H3 lysine 4 (H3K4) and H3K27 were mapped on the fertile floral buds, and a great deal of pollen development-associated genes that were covalently modified by H3K4me3 and H3K27me3 were identified. Conclusions: Our study provids a deeper understanding into the gene expression and regulation network during pollen development and pollen wall formation in B. rapa, and enabled the identification of a set of candidate genes for further functional annotation. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC), a commonly diagnosed cancer often develops slowly from benign polyps called adenoma to carcinoma. Altered gut microbiota is implicated in colorectal carcinogenesis. It is warranted to find non-invasive progressive microbiota biomarkers that can reflect the dynamic changes of the disease. This study aimed to identify and evaluate potential progressive fecal microbiota gene markers for diagnosing advanced adenoma (AA) and CRC. Results: Metagenome-wide association was performed on fecal samples from different cohorts of 871 subjects (247 CRC, 234 AA, and 390 controls). We characterized the gut microbiome, identified microbiota markers, and further constructed a colorectal neoplasms classifier in 99 CRC, 94 AA, and 62 controls, and validated the results in 185 CRC, 140 AA, and 291 controls from 3 independent cohorts. 21 species and 277 gene markers were identified whose abundance was significantly increased or decreased from normal to AA and CRC. The progressive gene markers were distributed in metabolic pathways including amino acid and sulfur metabolism. A diagnosis model consisting of four effect indexes was constructed based on the markers, the sensitivities of the Adenoma Effect Index 1 for AA, Adenoma Effect Index 2 for high-grade dysplasia (HGD) adenoma were 71.3% and 76.5%, the specificities were 90.5% and 90.3%, respectively. CRC Effect Index 1 for all stages of CRC and CRC Effect Index 2 for stage III–IV CRC to predict CRC yielded an area under the curve (AUC) of 0.839 (95% CI 0.804–0.873) and 0.857 (95% CI 0.793–0.921), respectively. Combining with fecal immunochemical test (FIT) significantly improved the sensitivity of CRC Effect Index 1 and CRC Effect Index 2 to 96.7% and 100%. Conclusions: This study reports the successful diagnosis model establishment and cross-region validation for colorectal advanced adenoma and carcinoma based on the progressive gut microbiota gene markers. The results suggested that the novel diagnosis model can significantly improve the diagnostic performance for advanced adenoma. [ABSTRACT FROM AUTHOR]

Background: Over several decades, a wide range of natural and artificial selection events in response to subtropical environments, intensive pasture and intensive feedlot systems have greatly changed the customary behaviour, appearance, and important economic traits of Shanghai Holstein cattle. In particular, the longevity of the Shanghai Holstein cattle population is generally short, approximately the 2nd to 3rd lactation. In this study, two complementary approaches, integrated haplotype score (iHS) and runs of homozygosity (ROH), were applied for the detection of selection signatures within the genome using genotyping by genome-reduced sequence data from 1092 cows. Results: In total, 101 significant iHS genomic regions containing selection signatures encompassing a total of 256 candidate genes were detected. There were 27 significant |iHS| genomic regions with a mean |iHS| score > 2. The average number of ROH per individual was 42.15 ± 25.47, with an average size of 2.95 Mb. The length of 78 % of the detected ROH was within the range of 1–2 MB and 2–4 MB, and 99 % were shorter than 8 Mb. A total of 168 genes were detected in 18 ROH islands (top 1 %) across 16 autosomes, in which each SNP showed a percentage of occurrence > 30 %. There were 160 and 167 genes associated with the 52 candidate regions within health-related QTL intervals and 59 candidate regions within reproduction-related QTL intervals, respectively. Annotation of the regions harbouring clustered |iHS| signals and candidate regions for ROH revealed a panel of interesting candidate genes associated with adaptation and economic traits, such as IL22RA1, CALHM3, ITGA9, NDUFB3, RGS3, SOD2, SNRPA1, ST3GAL4, ALAD, EXOSC10, and MASP2. In a further step, a total of 1472 SNPs in 256 genes were matched with 352 cis-eQTLs in 21 tissues and 27 trans-eQTLs in 6 tissues. For SNPs located in candidate regions for ROH, a total of 108 cis-eQTLs in 13 tissues and 4 trans-eQTLs were found for 1092 SNPs. Eighty-one eGenes were significantly expressed in at least one tissue relevant to a trait (P value < 0.05) and matched the 256 genes detected by iHS. For the 168 significant genes detected by ROH, 47 gene-tissue pairs were significantly associated with at least one of the 37 traits. Conclusions: We provide a comprehensive overview of selection signatures in Shanghai Holstein cattle genomes by combining iHS and ROH. Our study provides a list of genes associated with immunity, reproduction and adaptation. For functional annotation, the cGTEx resource was used to interpret SNP-trait associations. The results may facilitate the identification of genes relevant to important economic traits and can help us better understand the biological processes and mechanisms affected by strong ongoing natural or artificial selection in livestock populations. [ABSTRACT FROM AUTHOR]

As one of the largest transcription factor families with complex functional differentiation in plants, the MYB transcription factors (MYB TFs) play important roles in the physiological and biochemical processes of plant growth and development. Male reproductive development, an essential part of sexual reproduction in flowering plants, is undoubtedly regulated by MYB TFs. In this review, we summarize the roles of the MYB TFs involved in the three stages of male reproductive development: pollen grains formation and maturation, filament elongation and anther dehiscence, and fertilization. Also, the potential downstream target genes and upstream regulators of these MYB TFs are discussed. Furthermore, we propose the underlying regulatory mechanisms of these MYB TFs: (1) A complex network of MYB TFs regulates various aspects of male reproductive development; (2) MYB homologous genes in different species may be functionally conserved or differentiated; (3) MYB TFs often form regulatory complexes with bHLH TFs. [Display omitted] • MYB TFs regulate various aspects of male reproductive development. • The target genes of relevant MYB TFs are various. • Different upstream factors regulate relevant MYB TFs to function. [ABSTRACT FROM AUTHOR]

Background The safe use of medications in pregnant females, their embryos and in offspring is important. The aim of the present study was to evaluate embryotoxicity of metformin ( MET) compared with other hypoglycemic drugs (rosiglitazone [ RSG] and glimepiride [ GLIM]), the anticancer drug 5-fluorouracil (5- FU), the anti-epileptic drug diphenylhydantoin ( DPH), the antibiotic penicillin G ( Pen G), and the cyclo-oxygenase ( COX)-2 inhibitor nimesulide ( NIM) in an embryonic stem cell test ( EST). Methods Differences in the expression of developmental marker genes following treatment with the test compounds during the course of differentiation (from embryonic stem cell D3 ( D3 cells) to myocardial cells) were determined using real-time quantitative polymerase chain reaction. In these studies, 5- FU was used as a positive control and Pen G was used as a negative control. The cytotoxicity of these drugs against D3 cells and 3 T3 fibroblasts was determined by the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2 H-tetrazolium bromide ( MTT) assay. Embryotoxicity was classified according to the prediction model of EST. Results At concentrations >800 μg/mL MET had a greater cytotoxic effect on D3 cells than 3 T3 fibroblasts. At the highest concentration of MET (5 mg/mL), the cell viability of D3 cells and 3 T3 fibroblasts was <10% and >30%, respectively. The size of the embryonic body ( EB) differentiation area was almost the same over the concentration range 50-200 μg/mL MET, and there was no significant difference in EB differentiation area until a concentration of 400 μg/mL MET. At a concentration of 800 μg/mL MET, the size of EB outgrowth was significantly reduced. The same assays revealed GLIM, RSG, and NIM to be weakly embryotoxic substances. Conclusions Based on the EST, MET can be classified as a weakly embryotoxic substance, which suggests that it should be prescribed with caution to pregnant women with gestational diabetes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Integrated analysis of multi-omics datasets yields insight into EE liver toxicity. [•] Cholestasis and oxidative stress are involved in EE-induced liver injury. [•] Anti-cholestatic adaptive mechanism is mediated through ABC transporters pathway. [ABSTRACT FROM AUTHOR]