SGK1 promotes the lipid accumulation via regulating the transcriptional activity of FOXO1 in bovine.

OBJECTIVES: Serum/glucocorticoid-inducible kinase 1 (SGK1) gene encodes a serine/threonine protein kinase that plays an essential role in cellular stress response and regulation of multiple metabolic processes. However, its role in bovine adipogenesis remains unknown. In this study, we aimed to clarify the role of SGK1 in bovine lipid accumulation and improvement of meat quality. METHODS: Preadipocytes were induced to differentiation to detect the temporal expression pattern of SGK1. Heart, liver, lung, spleen, kidney, muscle and fat tissues were collected to detect its tissue expression profile. Recombinant adenovirus and the lentivirus were packaged for overexpression and knockdown. Oil Red O staining, quantitative real-time PCR, Western blot analysis, Yeast two-hybrid assay, luciferase assay and RNA-seq were performed to study the regulatory mechanism of SGK1. RESULTS: SGK1 showed significantly higher expression in adipose and significantly induced expression in differentiated adipocytes. Furthermore, overexpression of SGK1 greatly promoted adipogenesis and inhibited proliferation, which could be shown by the remarkable increasement of lipid droplet, and the expression levels of adipogenic marker genes and cell cycle-related genes. Inversely, its knockdown inhibited adipogenesis and facilitated proliferation. Mechanistically, SGK1 regulates the phosphorylation and expression of two critical proteins of FoxO family, FOXO1/FOXO3. Importantly, SGK1 attenuates the transcriptional repression role of FOXO1 for PPARγ via phosphorylating the site S256, then promoting the bovine fat deposition. CONCLUSIONS: SGK1 is a required epigenetic regulatory factor for bovine preadipocyte proliferation and differentiation, which contributes to a better understanding of fat deposition and meat quality improvement in cattle.

Identification of core genes affecting IMF deposition in bovine.

Intramuscular fat (IMF) content is an important economic factor in beef production. However, knowledge on the key factors controlling bovine IMF is limited. In this study, using weighted gene co-expression network analysis (WGCNA), nine modules were identified and the number of transcripts in these modules ranged from 36 to 3191. Two modules were found to be significantly associated with fat deposition and three genes (TCAP, MYH7, and TNNC1) were further identified by Protein-protein interaction (PPI), which may be the hub genes regulating bovine IMF deposition. In addition, considering the genetic variation, the PCK1 gene was found by functional enrichment analysis of overlapping genes, which was previously reported to be involved in IMF deposition. We noted that the core promoter region of buffalo PCK1 binds to transcription factors involved in lipid metabolism while cattle PCK1 binds transcription factors involved in muscle development. The results suggest that PCK1 participated in IMF deposition of buffalo and cattle in different ways. In summary, gene expression networks and new candidate genes associated with IMF deposition identified in this study. This would lay the foundation for further research into the molecular regulatory mechanisms underlying bovine IMF deposition.

miR-302b promotes bovine preadipocyte differentiation and inhibits proliferation by targeting CDK2.

MicroRNAs have been recently reported to act as key regulators of adipogenesis, a multifactorial complex process. One miRNA, miR-302b, is an important regulator of cell proliferation and differentiation and controls cancer development, but we speculate that miR-302b may also regulate bovine adipogenesis. Herein we have evaluated the role of this miRNA in bovine adipocyte differentiation using quantitative Real-Time Polymerase Chain Reaction (qRT-PCR), Oil Red O staining, a dual-luciferase reporter. CDK2 was identified as the target gene of miR-302b, and miR-302b agomir promoted mRNA and protein expression levels of adipocyte-specific genes. In addition, a CCK-8 kit was used to show that miR-302b agomir, but not the negative control, inhibits preadipocyte proliferation. In conclusion, miR-302b promotes bovine preadipocyte differentiation and inhibits proliferation by targeting CDK2.

Genome-Wide Identification and Characterization of Bovine Fibroblast Growth Factor (FGF) Gene and Its Expression during Adipocyte Differentiation.

Fibroblast growth factor (FGF) family genes are a class of polypeptide factors with similar structures that play an important role in regulating cell proliferation and differentiation, nutritional metabolism, and neural activity. In previous studies, the FGF gene has been widely studied and analyzed in many species. However, the systematic study of the FGF gene in cattle has not been reported. In this study, 22 FGF genes distributed on 15 chromosomes were identified in the Bos taurus genome and clustered into seven subfamilies according to phylogenetic analysis and conservative domains. Collinear analysis showed that the bovine FGF gene family was homologous to Bos grunniens, Bos indicus, Hybrid-Bos taurus, Bubalus bubalis, and Hybrid-Bos indicus, and tandem replication and fragment replication were the key driving forces for the expansion of the gene family. Tissue expression profiling showed that bovine FGF genes were commonly expressed in different tissues, with FGF1, FGF5, FGF10, FGF12, FGF16, FGF17, and FGF20 being highly expressed in adipose tissue. In addition, real-time fluorescence quantitative PCR (qRT-PCR) detection showed that some FGF genes were differentially expressed before and after adipocyte differentiation, indicating their diverse role in the formation of lipid droplets. This study made a comprehensive exploration of the bovine FGF family and laid a foundation for further study on the potential function in the regulation of bovine adipogenic differentiation.

Genome-wide identification of cyclin-dependent kinase (CDK) genes affecting adipocyte differentiation in cattle.

BACKGROUND: Cyclin-dependent kinases (CDKs) are protein kinases regulating important cellular processes such as cell cycle and transcription. Many CDK genes also play a critical role during adipogenic differentiation, but the role of CDK gene family in regulating bovine adipocyte differentiation has not been studied. Therefore, the present study aims to characterize the CDK gene family in bovine and study their expression pattern during adipocyte differentiation. RESULTS: We performed a genome-wide analysis and identified a number of CDK genes in several bovine species. The CDK genes were classified into 8 subfamilies through phylogenetic analysis. We found that 25 bovine CDK genes were distributed in 16 different chromosomes. Collinearity analysis revealed that the CDK gene family in Bos taurus is homologous with Bos indicus, Hybrid-Bos taurus, Hybrid Bos indicus, Bos grunniens and Bubalus bubalis. Several CDK genes had higher expression levels in preadipocytes than in differentiated adipocytes, as shown by RNA-seq analysis and qPCR, suggesting a role in the growth of emerging lipid droplets. CONCLUSION: In this research, 185 CDK genes were identified and grouped into eight distinct clades in Bovidae, showing extensively homology. Global expression analysis of different bovine tissues and specific expression analysis during adipocytes differentiation revealed CDK4, CDK7, CDK8, CDK9 and CDK14 may be involved in bovine adipocyte differentiation. The results provide a basis for further study to determine the roles of CDK gene family in regulating adipocyte differentiation, which is beneficial for beef quality improvement.

Mapping of novel powdery mildew resistance gene(s) from Agropyron cristatum chromosome 2P.

KEY MESSAGE: A physical map of Agropyron cristatum 2P chromosome was constructed for the first time and the novel powdery mildew resistance gene(s) from chromosome 2P was(were) also mapped. Agropyron cristatum (L.) Gaertn. (2n = 28, PPPP), a wild relative of common wheat, is highly resistant to powdery mildew. Previous studies showed that wheat-A. cristatum 2P disomic addition line II-9-3 displayed high resistance to powdery mildew, and the resistance was attributable to A. cristatum chromosome 2P. To utilize and physically map the powdery mildew resistance gene(s), 15 wheat-A. cristatum 2P translocation lines and three A. cristatum 2P deletion lines with different chromosomal segment sizes, obtained from II-9-3 using 60Co-γ ray irradiation, were characterized using cytogenetic and molecular marker analysis. A. cristatum 2P chromosomal segments in the translocations were translocated to different wheat chromosomes, including 1A, 4A, 5A, 6A, 7A, 1B, 2B, 3B, 7B, 3D, 4D, and 6D. A physical map of the 2P chromosome was constructed with 82 STS markers, consisting of nine bins with 34 markers on 2PS and eight bins with 48 markers on 2PL. The BC1F2 populations of seven wheat-A. cristatum 2P translocation lines (2PT-3, 2PT-4, 2PT-5, 2PT-6, 2PT-8, 2PT-9, and 2PT-10) were developed by self-pollination, tested with powdery mildew and genotyped with 2P-specific STS markers. From these results, the gene(s) conferring powdery mildew resistance was(were) located on 2PL bin FL 0.66-0.86 and 19 2P-specific markers were identified in this bin. Moreover, two new powdery mildew-resistant translocation lines (2PT-4 and 2PT-5) with small 2PL chromosome segments were obtained. The newly developed wheat lines with powdery mildew resistance and the closely linked molecular markers will be valuable for wheat disease breeding in the future.

Physical mapping of Agropyron cristatum chromosome 6P using deletion lines in common wheat background.

KEY MESSAGE: Genetically stable deletion lines of Agropyron cristatum chromosome 6P in common wheat background were generated, which allowed for physical mapping of 255 6P-specific STS markers and leaf rust resistance gene(s). Chromosomal deletion lines are valuable tools for gene discovery and localization. The chromosome 6P of Agropyron cristatum (2n = 4x = 28, PPPP) confers many desirable agronomic traits to common wheat, such as higher grain number per spike, multiple fertile tiller number, and enhanced resistance to certain diseases. Although many elite genes from A. cristatum have been identified, their chromosomal locations were largely undetermined due to the lack of A. cristatum 6P deletion lines. In this study, various A. cristatum 6P deletion lines were developed using a wheat-A. cristatum 6P disomic addition line 4844-12 subjected to (60)Co-γ irradiation as well as an Aegilops cylindrica gametocidal chromosome. Twenty-six genetically stable A. cristatum 6P deletion lines in the genetic background of common wheat were obtained, and their genetic constitutions were elucidated by genomic in situ hybridization (GISH) and sequence-tagged site (STS) markers specific to A. cristatum chromosome 6P. Moreover, 255 novel chromosome 6P-specific STS markers were physically mapped to 14 regions of chromosome 6P. Field evaluation of leaf rust resistance of various deletion lines and BC1F2 populations indicated that the A.cristatum chromosome 6P-originated leaf rust resistance gene(s) was located in the region 6PS-0.81-1.00. This study will provide not only useful tools for characterization and utilization of wheat materials with alien chromosomal segments, but also novel wheat germplasms potentially valuable in wheat breeding and improvement.

Cytological and molecular analysis of wheat - Agropyron cristatum translocation lines with 6P chromosome fragments conferring superior agronomic traits in common wheat.

Agropyron cristatum (2n = 4x = 28, PPPP) is a wild relative of common wheat and confers several desirable agronomic traits to wheat, such as high grain number per spike and enhanced resistance to certain diseases. Development of wheat - A. cristatum 6P translocation lines facilitates its utilization in wheat improvement. In this study, 26 wheat - A. cristatum 6P translocation lines were characterized by in situ hybridization (ISH) and 6P-specific sequence-tagged-site (STS) markers. These translocation lines carried different 6P chromosomal segments, which covered the whole 6P chromosome. FISH results showed that 15, 5, and 6 lines were translocated onto wheat A, B, and D genomes, respectively. Compared with the previous reports, a fine physical map of 6P chromosome was constructed, consisting of 31 chromosomal bins with 255 STS markers. Twelve translocation lines containing 6PS13∼14 chromosomal bins were highly resistant to leaf rust. Two lines showed high grain number per spike, and three lines displayed both enhanced grain number per spike and thousand-grain weight. Development of wheat - A. cristatum 6P translocation lines will not only provide novel wheat germplasm for wheat breeding but also be helpful to broaden the genetic basis of common wheat.

Characterization of feed efficiency-related key signatures molecular in different cattle breeds.

Feed efficiency is a major constraint in the beef industry and has a significant negative correlation with residual feed intake (RFI). RFI is widely used as a measure of feed efficiency in beef cattle and is independent of economic traits such as body weight and average daily gain. However, key traits with commonality or specificity among beef cattle breeds at the same level of RFI have not been reported. Accordingly, the present study hypothesized that signatures associated with feed efficiency would have commonality or specificity in the liver of cattle breeds at the same RFI level. By comparing and integrating liver transcriptome data, we investigated the critical signatures closely associated with RFI in beef cattle using weighted co-expression network analysis, consensus module analysis, functional enrichment analysis and protein network interaction analysis. The results showed that the consensus modules in Angus and Charolais cattle were negatively correlated, and four (turquoise, red, tan, yellow) were significantly positively correlated in Angus liver, while (turquoise, red) were significantly negatively correlated in Charolais liver. These consensus modules were found to be primarily involved in biological processes such as substance metabolism, energy metabolism and gene transcription, which may be one of the possible explanations for the difference in feed efficiency between the two beef breeds. This research also identified five key candidate genes, PLA2G12B, LCAT, MTTP, LCAT, ABCA1 and FADS1, which are closely associated with hepatic lipid metabolism. The present study has identified some modules, genes and pathways that may be the major contributors to the variation in feed efficiency among different cattle breeds, providing a new perspective on the molecular mechanisms of feed efficiency in beef cattle and a research basis for investigating molecular markers associated with feed efficiency in beef cattle.

Construction of a molecular regulatory network related to fat deposition by multi-tissue transcriptome sequencing of Jiaxian red cattle.

Intramuscular fat (IMF) refers to the fat that accumulates between muscle bundles or within muscle cells, whose content significantly impacts the taste, tenderness, and flavor of meat products, making it a crucial economic characteristic in livestock production. However, the intricate mechanisms governing IMF deposition, involving non-coding RNAs (ncRNAs), genes, and complex regulatory networks, remain largely enigmatic. Identifying adipose tissue-specific genes and ncRNAs is paramount to unravel these molecular mysteries. This study, conducted on Jiaxian red cattle, harnessed whole transcriptome sequencing to unearth the nuances of circRNAs and miRNAs across seven distinct tissues. The interplay of these ncRNAs was assessed through differential expression analysis and network analysis. These findings are not only pivotal in unveiling the intricacies of fat deposition mechanisms but also lay a robust foundation for future research, setting the stage for enhancing IMF content in Jiaxian red cattle breeding.

Genome-wide identification of bovine ADAMTS gene family and analysis of its expression profile in the inflammatory process of mammary epithelial cells.

ADAM metallopeptidase with thrombospondin type 1 motif (ADAMTS) are secreted, multi-domain matrix-related zinc endopeptidases that play a role in organogenesis, assembly and degradation of extracellular matrix (ECM), cancer and inflammation. Genome-wide identification and analysis of the bovine ADAMTS gene family has not yet been carried out. In this study, 19 ADAMTS family genes were identified in Bos taurus by genome-wide bioinformatics analysis, and they were unevenly distributed on 12 chromosomes. Phylogenetic analysis shows that the Bos taurus ADAMTS are divided into eight subfamilies, with highly consistent gene structures and motifs within the same subfamily. Collinearity analysis showed that the Bos taurus ADAMTS gene family is homologous to other bovine subfamily species, and many ADAMTS genes may be derived from tandem replication and segmental replication. In addition, based on the analysis of RNA-seq data, we found the expression pattern of ADAMTS gene in different tissues. Meanwhile, we also analyzed the expression profile of ADAMTS gene in the inflammatory response of bovine mammary epithelial cells (BMECs) stimulated by LPS by qRT-PCR. The results can provide ideas for understanding the evolutionary relationship and expression pattern of ADAMTS gene in Bovidae, and clarify the theoretical basis of the function of ADAMTS in inflammation.

Identification of key genes in bovine muscle development by co-expression analysis.

Background: Skeletal muscle is not only an important tissue involved in exercise and metabolism, but also an important part of livestock and poultry meat products. Its growth and development determines the output and quality of meat to a certain extent, and has an important impact on the economic benefits of animal husbandry. Skeletal muscle development is a complex regulatory network process, and its molecular mechanism needs to be further studied. Method: We used a weighted co-expression network (WGCNA) and single gene set enrichment analysis (GSEA) to study the RNA-seq data set of bovine tissue differential expression analysis, and the core genes and functional enrichment pathways closely related to muscle tissue development were screened. Finally, the accuracy of the analysis results was verified by tissue expression profile detection and bovine skeletal muscle satellite cell differentiation model in vitro (BSMSCs). Results: In this study, Atp2a1, Tmod4, Lmod3, Ryr1 and Mybpc2 were identified as marker genes in muscle tissue, which are mainly involved in glycolysis/gluconeogenesis, AMPK pathway and insulin pathway. The assay results showed that these five genes were highly expressed in muscle tissue and positively correlated with the differentiation of bovine BSMSCs. Conclusions: In this study, several muscle tissue characteristic genes were excavated, which may play an important role in muscle development and provide new insights for bovine molecular genetic breeding.

Proteomic and metabolomic analysis of ageing beef exudate to determine that iron metabolism enhances muscle protein and lipid oxidation.

The study aimed to assess differences in proteomic and metabolite profiles in ageing (1, 2, 4, and 6 days at 4 °C) beef exudates and determine their relationship with beef muscle iron metabolism and oxidation. Proteomic and metabolomic analyses identified 877 metabolites and 1957 proteins. The joint analysis identified 24 differential metabolites (DMs) and 56 differentially expressed proteins (DEPs) involved in 15 shared pathways. Ferroptosis was identified as the only iron metabolic pathway, and 4 DMs (l-glutamic acid, arachidonic acid, glutathione and gamma-glutamylcysteine) and 5 DEPs (ferritin, phospholipid hydroperoxide glutathione peroxidase, heme oxygenase 1, major prion protein, and acyl-CoA synthetase long chain family member 4) were involved in iron metabolism by regulating heme and ferritin degradation, Fe2+ and Fe3+ conversion, arachidonic acid oxidation and inactivation of glutathione peroxidase (GPX) 4, leading to increased levels of free iron, ROS, protein and lipid oxidation (P < 0.05). Overall, abnormal iron metabolism during ageing induced oxidative stress in muscle tissue.

Identifying Key Genes and Functionally Enriched Pathways of Diverse Adipose Tissue Types in Cattle.

Background: Fat is a tissue that not just stores energy and plays a protective role; it is also a vital endocrine organ that generates and integrates signals to influence metabolism. Meanwhile, the excessive accumulation of lipids in adipose tissue can lead to metabolic disturbance and diseases. To date, the complicated molecular mechanisms of bovine adipose tissue are still unknown. This study aimed to identify key genes and functionally enriched pathways in various adipose tissue types. Results: The RNAseq data of 264 samples were downloaded from Gene Expression Omnibus (GEO) and analyzed by weighted gene co-expression network analysis (WGCNA). We identified 19 modules that significantly associated with at least one adipose tissue type. The brown module from GSE39618 was most closely associated with intramuscular fat tissue, which contained 550 genes. These genes were significantly enriched in pathways that related to inflammation and disease, such as TNF signaling pathway, IL-17 signaling pathway, and NF-kappa B signaling pathway. The pink module (GSE39618) that contained 58 genes was most closely associated with omental fat tissue. The turquoise (GSE39618), blue (GSE116775), and yellow (GSE65125) module were most closely associated with subcutaneous fat tissue. Genes in these modules were significantly enriched in pathways related to fat metabolism, such as the PPAR signaling pathway, fatty acid metabolism and PI3K-Akt signaling pathway. At last, key genes for intramuscular fat (PTGS2 and IL6), omental fat (ARHGEF5 and WT1), and subcutaneous fat (KIT, QR6Q1, PKD2L1, etc.) were obtained and verified. In addition, it was found that IL10 and VCAM1 might be potential genes to distinguish adipose and muscle. Conclusion: The study applied WGCNA to generate a landscape of adipose tissue and provide a basis for identifying potential pathways and hub genes of different adipose tissue types.

Genome-wide identification and expression profiling analysis of Wnt family genes affecting adipocyte differentiation in cattle.

The Wnt family features conserved glycoproteins that play roles in tissue regeneration, animal development and cell proliferation and differentiation. For its functional diversity and importance, this family has been studied in several species, but not in the Bovinae. Herein we identified 19 Wnt genes in cattle, and seven other species of Bovinae, and described their corresponding protein properties. Phylogenetic analysis clustered the 149 Wnt proteins in Bovinae, and 38 Wnt proteins from the human and mouse into 12 major clades. Wnt genes from the same subfamilies shared similar protein motif compositions and exon-intron patterns. Chromosomal distribution and collinearity analysis revealed that they were conservative in cattle and five species of Bovinae. RNA-seq data analysis indicated that Wnt genes exhibited tissue-specific expression in cattle. qPCR analysis revealed a unique expression pattern of each gene during bovine adipocytes differentiation. Finally, the comprehensive analysis indicated that Wnt2B may regulate adipose differentiation by activating FZD5, which is worthy of further study. Our study presents the first genome-wide study of the Wnt gene family in Bovinae, and lays the foundation for further functional characterization of this family in bovine adipocytes differentiation.

Identification of key genes and functional enrichment pathways involved in fat deposition in Xinyang buffalo by WGCNA.

The Xinyang buffalo is a valuable and endangered domestic heritage resource in the Dabie Mountain region in China. With the increasing mechanization of agriculture, the Xinyang buffalo, mainly used for labor, faces unprecedented challenges. One of the feasible approaches to conserve and expand the species is to transfer Xinyang buffalo from service-use to meat-use, but the main hindrance to this transformation is the inferior meat quality of Xinyang buffalo, which is not popular with consumers. Based on the above, this study was conducted to evaluate the growth performance (n = 120) and slaughter performance (n = 3) of Xinyang buffalo and to measure the amino acid levels of the eye muscle (EM), and assess the meat quality. Later, transcriptome sequencing was performed on the subcutaneous fat of the back at six (n = 3) and 30 months of age (n = 3), together with the excavation of candidate genes associated with fat deposition using the weighted co-expression network analysis (WGCNA) method. The results showed that the slaughter rate of Xinyang buffalo was 43.09%, net meat percentage was 33.04%, the ocular area was 59.16 ± 7.58, the backfat thickness was 1.03 ± 0.16, and meat bone ratio was 3.29. The total amino acid contents were 0.63 g per gram of beef, which contained 0.05 g of essential amino acids, and the three most abundant amino acids were Ser (447.17 mg/g), Asp (29.8 mg/g), and Pro (27.24 mg/g). The WGCNA results showed that six phenotypes measured were significantly correlated with the turquoise module (r > 0.97, P < 0.001), and the genes in these modules were significantly enriched in the pathways related to substance metabolism and energy metabolisms, such as metabolic pathways, citrate cycle, and fatty acid metabolism. Meanwhile, six key candidate genes (FH, MECR, GPI, PANK3, ATP6V1A, PHYH) were identified, which were associated with growth and development, fat deposition, and intra-muscular amino acid levels (P < 0.05). In short, this study provides another feasible way to preserve buffalo and enriches the theory of its molecular genetic breeding.

Identification of Key Genes Associated With Early Calf-Hood Nutrition in Subcutaneous and Visceral Adipose Tissues by Co-Expression Analysis.

Background: Substantive evidence has confirmed that nutrition state is associated with health risk and the onset of pubertal and metabolic profile. Due to heterogeneity, adipose tissues in different anatomical positions tend to show various metabolic mechanisms for nutrition. To date, the complicated molecular mechanisms of early calf-hood nutrition on bovine adipose tissue are still largely unknown. This study aimed to identify key genes and functionally enriched pathways associated with early calf-hood nutrition in visceral and subcutaneous adipose tissue. Results: The RNA-seq data of visceral and subcutaneous adipose tissues of calves feeding on low and high dietary nutrition for more than 100 days were downloaded and analyzed by weighted gene co-expression network analysis (WGCNA). Two modules that positively associated with a low plane of nutrition diet and two modules with a high plane of nutrition diet were identified in the subcutaneous adipose tissue. The blue and yellow modules, most closely associated with low and high nutrition, were selected for the functional enrichment analysis and exploration of hub genes. The results showed that genes in the blue module were significantly enriched in pathways that related to fat metabolism, reproduction, and cell communication. Genes in the yellow module were enriched in pathways related to fat metabolism, reproduction, cell proliferation, and senescence. Meanwhile, the blue and brown modules in visceral adipose tissue were most closely associated with low and high nutrition, respectively. Notably, genes of the blue module were significantly enriched in pathways related to substance metabolism, and genes in the brown module were significantly enriched in energy metabolism and disease pathways. Finally, key genes in subcutaneous adipose tissue for low nutrition (PLCG1, GNA11, and ANXA5) and high nutrition (BUB1B, ASPM, RRM2, PBK, NCAPG, and MKI67), and visceral adipose tissue for low nutrition (RPS5, RPL4, RPL14, and RPLP0) and high nutrition (SDHA and AKT1) were obtained and verified. Conclusion: The study applied WGCNA to identify hub genes and functionally enriched pathways in subcutaneous and visceral adipose tissue and provided a basis for studying the effect of early calf-hood nutrition on the two adipose tissue types.

Identification of 5P Chromosomes in Wheat-Agropyron cristatum Addition Line and Analysis of Its Effect on Homologous Pairing of Wheat Chromosomes.

As an important wheat wild relative, the P genome of Agropyron cristatum (L.) Gaertn. (2n = 4x = 28) is very valuable for wheat improvement. A complete set of wheat-A. cristatum disomic addition lines is the basis for studying the genetic behavior of alien homoeologous chromosomes and exploring and utilizing the excellent genes. In this study, a wheat-A. cristatum derivative II-11-1 was proven to contain a pair of 5P chromosomes and a pair of 2P chromosomes with 42 wheat chromosomes by analyzing the fluorescence in situ hybridization (FISH) and expressed sequence tag (EST) markers. Additionally, cytological identification and field investigation showed that the 5P chromosome can weaken the homologous pairing of wheat chromosomes and promote the pairing between homoeologous chromosomes. This provides new materials for studying the mechanism of the alien gene affecting the homologous chromosome pairing and promoting the homoeologous pairing of wheat. In addition, chromosomal structural variants have been identified in the progeny of II-11-1. Therefore, the novel 5P addition line might be used as an important genetic material to widen the genetic resources of wheat.

Genome-wide identification of the jumonji C domain- containing histone demethylase gene family in wheat and their expression analysis under drought stress.

Methylation and demethylation of histone play a crucial role in regulating chromatin formation and gene expression. The jumonji C (JmjC) domain-containing proteins are demethylases that are involved in regulating epigenetic modification in plants. In our study, the JmjC genes in Triticum aestivum L., Triticum turgidum L., Triticum dicoccoides L., Triticum urartu L., and Aegilops tauschii L. were identified. Phylogenetic relationship and colinearity analysis revealed that the wheat JmjC genes were conserved in A, B, and D subgenomes during evolution. Cis-acting elements analysis showed that elements related to stress response, hormone response, and light response were found in wheat JmjC genes. The expression of JmjC genes was affected by tissue types and developmental stages, and members of the same subfamily tended to have similar expression patterns in wheat. They also showed a unique expression pattern in root during PEG (Polyethylene glycol) treatment. In conclusion, comprehensive analysis indicated that three members (Tr-1A-JMJ2, Tr-1B-JMJ2, and Tr-1D-JMJ2) might be regulated by several hormones and function in the early stages of drought stress, while eight members (Tr-1B-JMJ3, Tr-4B-JMJ1, Tr-7A-JMJ1, etc.) displayed a significantly high expression after 24 h of PEG treatment, indicating a role in the later stages of drought stress. This research presents the first genome-wide study of the JmjC family in wheat, and lays the foundation for promoting the study of their functional characterization in wheat drought resistance.

Weighted Gene Co-Expression Network Analysis Identifies Key Modules and Central Genes Associated With Bovine Subcutaneous Adipose Tissue.

Background: Fat deposition is an important economic trait in livestock and poultry production. However, the relationship between various genes and signal pathways of fat deposition is still unclear to a large extent. The purpose of this study is to analyze the potential molecular targets and related molecular pathways in bovine subcutaneous adipose tissue. Results: We downloaded the GSE116775 microarray dataset from Gene Expression Omnibus (GEO). The weighted gene co-expression network (WGCNA) was used to analyze the gene expression profile, and the key gene modules with the highest correlation with subcutaneous adipose tissue were identified, and the functional enrichment of the key modules was analyzed. Then, the "real" Hub gene was screened by in-module analysis and protein-protein interaction network (PPI), and its expression level in tissue samples and adipocytes was verified. The study showed that a total of nine co-expression modules were identified, and the number of genes in these modules ranged from 101 to 1,509. Among them, the blue module is most closely related to subcutaneous adipose tissue, containing 1,387 genes. These genes were significantly enriched in 10 gene ontologies including extracellular matrix organization, biological adhesion, and collagen metabolic process, and were mainly involved in pathways including ECM-receptor interaction, focal adhesion, cAMP signaling pathway, PI3K-AKT signaling pathway, and regulation of lipolysis in adipocytes. In the PPI network and coexpression network, five genes (CAV1, ITGA5, COL5A1, ABL1, and HSPG2) were identified as "real" Hub genes. Analysis of Hub gene expression by dataset revealed that the expression of these Hub genes was significantly higher in subcutaneous adipose tissue than in other tissues. In addition, real-time fluorescence quantitative PCR (qRT-PCR) analysis based on tissue samples and adipocytes also confirmed the above results. Conclusion: In this study, five key genes related to subcutaneous adipose tissue were discovered, which laid a foundation for further study of the molecular regulation mechanism of subcutaneous adipose tissue development and adipose deposition.