Identification of hub genes associated with follicle development in multiple births sheep by WGCNA

Identification of Key Biomarkers of Growth-Related Traits in the Bay Scallop Argopecten irradians irradians via Multi-omics Analysis Strategies

In an attempt to promote and advance molecular-assisted selective breeding of shellfish, in this study, gills from selected (shell color as the marker trait and growth performance as the target trait) and unselected Argopecten irradians irradians were sampled. 2b-restriction site-associated DNA sequencing, genome-wide association study, comparative transcriptome, comparative small RNA transcriptome, miRNA-mRNA integrated analysis, quantitative real-time reverse transcription-polymerase chain reaction, and weighted gene co-expression network analysis were used to identify candidate SNPs, mRNAs, miRNAs, and miRNA/mRNA pairs with potential selective breeding value at a genomic scale in A. irradians irradians. The results revealed that a total of 6 significant SNPs were correlated closely with at least two examined growth-related traits. In addition, a total of 10 mRNAs and 7 miRNAs were identified to have positive correlations with shell length, shell height, shell width, total weight, and shell color. These candidate mRNAs and miRNAs may form 11 miRNA-mRNA pairs, which have great potential for developing molecular markers for molecular-assisted selective breeding of A. irradians irradians. The findings of this study will benefit the development of molecular-assisted breeding techniques in bay scallop aquaculture.

Single nucleotide polymorphism-based analysis of linkage disequilibrium and runs of homozygosity patterns of indigenous sheep in the southern Taklamakan desert

Runs of Homozygosity (ROH) are homozygous genomic fragments inherited from parents to offspring. ROH can be used to indicate the level of inbreeding, as well as to identify possible signatures of artificial or natural selection. Indigenous sheep populations on the southern edge of the Taklimakan Desert have evolved unique genetic traits adapted to extreme desert environments. In an attempt to better understand the adaptive mechanisms of these populations under harsh conditions, we used Illumina® Ovine SNP50K BeadChip to perform a genomic characterization of three recognized breeds (Duolang: n = 36, Hetian: n = 84, Qira black: n = 189) and one ecotypic breed (Kunlun: n = 27) in the region. Additionally, we assessed genomic inbreeding coefficients through ROH analysis, revealing insights into the inbreeding history of these populations. Subsequently, we retrieved candidate genes associated with economic traits in sheep from ROH islands in each breed. To better understand the autozygosity and distribution of ROH islands in these indigenous sheep breeds relative to international breeds, we also included three commercial mutton breeds (Poll Dorset: n = 108, Suffolk: n = 163, Texel: n = 150). The study revealed that among seven sheep breeds, Hetian exhibited the shortest linkage disequilibrium (LD) decay distance, while Kunlun demonstrated the highest LD levels. A total of 10,916 ROHs were obtained. The number of ROHs per breed ranged from 34 (Kunlun) to 2,826 (Texel). The length of ROH was mainly 1-5 Mb (63.54%). Furthermore, 991 candidate genes specific to indigenous sheep breeds were identified, including those associated with heat tolerance, adaptability, energy metabolism, reproduction, and immune response. These findings elucidate the genetic adaptation of indigenous sheep in the Taklimakan Desert, uncovering distinctive characteristics of indigenous sheep formation, and advocating for the conservation and genetic enhancement of local sheep populations.

Regulatory signatures involved in the cell cycle pathway contribute to egg production heterosis in chicken

BACKGROUND

Crossbreeding is widely promoted as an efficient strategy to improve the productivity in agriculture. The molecular mechanism underlying heterosis for egg production is always intriguing in chicken. The transcriptional dynamic changes play a crucial role in the formation of heterosis, but little is known for the egg production traits.

RESULTS

In present study, we measured the continuous manifestation of heterosis ranging from 2.67% to 10.24% for egg number in the crossbreds generated by reciprocal crossing White Leghorn and Beijing You chicken. The high-quality transcriptomes of ovary for purebreds (WW and YY) and crossbreds (WY and YW) in 5 laying stages were sequenced and integrated to identify regulatory networks relevant to the heterosis. We found highly conserved transcriptional features among 4 genetic groups. By using weighted gene co-expression network analysis (WGCNA), we obtained multiple gene co-expression modules that were significantly correlated with egg number for each group. The common KEGG pathways including apelin signaling pathway, cell cycle, ribosome, spliceosome and oxidative phosphorylation, were screened for the 2 crossbreds. Then, we identified consensus co-expression modules (CMs) that showed divergent expression pattern among crossbred (WY or YW) and purebreds (WW and YY). The hub genes of CMs were again overrepresented in the cell cycle pathway, and the crossbreds exhibited temporally complementary dominance of hub genes in the 5 laying stages. These results suggested that the crossbreds inherited from both parents to maintain the ovary function by cell cycle-related genes, contributing to the persistent heterosis for egg production. Furthermore, the dominant genes including MAD2L1, CHEK2 and E2F1 were demonstrated to function in ovarian follicle development and maturation and could be the candidate genes for egg production heterosis.

CONCLUSION

Our study characterized the dynamic profile of genome-wide gene expression in ovary and highlighted the role of dominant expression of cell cycle pathway genes in heterosis. These findings provided new insights for the molecular mechanism of egg production heterosis, which would facilitate the rational choice of suitable parents for producing crossbred chickens with higher egg production.

Genetic diversity and selection signatures in sheep breeds

Natural and artificial selection in domesticated animals can cause specific changes in genomic regions known as selection signatures. Our study used the integrated haplotype score (iHS) and Tajima's D tests within non-overlapping windows of 100 kb to identify selection signatures, in addition to genetic diversity and linkage disequilibrium estimates in 9498 sheep from breeds in Ireland (Belclare, Charollais, Suffolk, Texel, and Vendeen). The mean observed and expected heterozygosity for all the sheep breeds were 0.353 and 0.355, respectively. Suffolk had the least genetic variation and, along with Texel, had slower linkage disequilibrium decay. iHS and Tajima's D detected selection signatures for all breeds, with some regions overlapping, thus forming longer segments of selection signatures. Common selection signatures were identified across iHS and Tajima's D methods for all breeds, with Belclare and Texel having several common regions under positive selection. Several genes were detected within the selection signature regions, including ITGA4, TLR3, and TGFB2 related to the immune system against endoparasites; DLG1, ROBO2, MXI1, MTMR2, CEP57, and FAM78B related to reproductive traits; WDR70 related to milk traits; SCHM1 and MYH15 related to meat traits; and TAS2R4, TAS2R39, and TAS2R40 related to adaptive traits. In conclusion, our results demonstrated moderate genetic diversity in the sheep breeds and detected and characterized selection signatures harboring genes associated with reproductive traits, milk production, meat production, and adaptive traits such as endoparasite resistance.

Resolving and functional analysis of RNA editing sites in sheep ovaries and associations with litter size

Sheep litter size is a critical trait in mutton production. While litter size regulation in relation to DNA transcription have been rigorously investigated, the function of RNA editing remains less explored. To elucidate the mechanisms controlling sheep fecundity at the RNA editing level and identify pivotal RNA editing sites, this study scrutinised RNA editing sites (RESs) in follicular and luteal phases of ovaries from sheep with high and low fecundity, and the functions of population-specific RESs were subsequently analysed. A total of 2 182 475 RESs, 74.61% of which were A-to-I and C-to-U sites, were identified. These RESs were fairly evenly dispersed over the chromosomes, with 46.8% showing close clustering (inter-site distance < 300 bp). Notably, 93% were primarily situated in intronic and intergenic regions. In the follicular phase, pivotal RESs were found in the introns of genes including LPS responsive beige-like anchor, MCC regulator of Wnt signalling, and RWD domain containing 3, among others, and in the exon region of EvC ciliary complex subunit 2. In the luteal phase, RESs were observed in the introns of genes such as H/ACA ribonucleoprotein assembly factor and SDA1 domain-containing 1, and the exon and 3'UTR regions of polypeptide N-acetylgalactosaminyltransferase 15 and ilvB acetolactate synthase-like, respectively. High-fecundity sheep showed RESs in the follicular phase in genes such as fibrillin 1, cyclin-dependent kinase 6, and roundabout 1, and in genes such as autophagy-related 2B and versican in the luteal phase. Thirteen RESs specific to the follicular phase and eight specific to the luteal phase were identified in high-fecundity sheep ovaries. These RESs offer promising molecular targets and enhance understanding of multiple births in sheep from the perspective of posttranscriptional alterations.

Thyroid transcriptomic profiling reveals the differential regulation of lncRNA and mRNA related to prolificacy in small tail han sheep with FecB BB genotype

BACKGROUND

The thyroid gland is an important endocrine gland in animals that secretes thyroid hormones and acts on various organs throughout the body. lncRNAs are long non-coding RNAs that play an important role in animal reproduction; however, there is a lack of understanding of their expression patterns and potential roles in the thyroid gland of the Small Tail Han (STH) sheep. In this study, we used RNA-Seq technology to examine the transcriptome expression pattern of the thyroid from the luteal phase (LP) and follicular phase (FP) of FecB BB (MM) STH sheep.

RESULTS

We identified a total of 122 and 1287 differential expression lncRNAs (DELs) and differential expression mRNAs (DEGs), respectively, which were significantly differentially expressed. These DELs target genes and DEGs can be enriched in several signalling pathways related to the animal reproduction process.

CONCLUSIONS

The expression profiles of DELs and DEGs in thyroid glands provide a more comprehensive resource for elucidating the reproductive regulatory mechanisms of STH sheep.

Prognostic Model and Immune Response of Clear Cell Renal Cell Carcinoma Based on Co-Expression Genes Signature

BACKGROUND

The identification of reliable prognostic markers is crucial for optimizing patient management and improving clinical outcomes in clear cell renal cell carcinoma (ccRCC).

METHODS

We used the GSE89563 dataset from the GEO database and the Kidney Clear Cell Carcinoma (KIRC) dataset from the TCGA database to develop a prognostic model based on weighted gene co-expression network analysis (WGCNA) and non-negative matrix factorization (NMF) to predict disease progression and prognosis in ccRCC.

RESULT

We utilized WGCNA to identify risk genes and applied NMF to stratify high-risk populations in ccRCC. We characterized the immune gene features of these high-risk groups and ultimately developed a risk prediction model for ccRCC patients using a Lasso regression approach. The risk score was calculated as follows: Risk score = SUM (-0.136394797 ANK3 + 0.004238138 BIVM_ERCC5 - 0.046248451 C4orf19 - 0.036013206 F2RL3 - 0.125531316 GNG7 - 0.012698109 METTL7A + 0.078462369 MSTO1 - 0.050450656 PINK1 - 0.059446590 SLC16A12 - 0.039883686 SLC2A9 + 0.083310722 TLCD1 - 0.059801739 WDR72 + 0.071430088 ZNF117).

CONCLUSION

We develop a prognostic model for clear cell renal cell carcinoma and analyzed immune response in subgroups and confirmed protein-level expression concordance.

Expression patterns of housekeeping genes and tissue-specific genes in black goats across multiple tissues

Black goats are a significant meat breed in southern China. To investigate the expression patterns and biological functions of genes in various tissues of black goats, we analyzed housekeeping genes (HKGs), tissue-specific genes (TSGs), and hub genes (HUBGs) across 23 tissues. Additionally, we analyzed HKGs in 13 tissues under different feeding conditions. We identified 2968 HKGs, including six important ones. Interestingly, HKGs in grazing black goats demonstrated higher and more stable expression levels. We discovered a total of 9912 TSGs, including 134 newly identified ones. The number of TSGs for mRNA and lncRNA were nearly equal, with 127 mRNA TSGs expressed solely in one tissue. Additionally, the predicted functions of tissue-specific long non-coding RNAs (lncRNAs) targeting mRNAs corresponded with the physiological functions of the tissues.Weighted gene co-expression network analysis (WGCNA) constructed 30 modules, where the dark grey module consists almost entirely of HKGs, and TSGs are located in modules most correlated with their respective tissues. Additionally, we identified 289 HUBGs, which are involved in regulating the physiological functions of their respective tissues. Overall, these identified HKGs, TSGs, and HUBGs provide a foundation for studying the molecular mechanisms affecting the genetic and biological processes of complex traits in black goats.

Long non-coding RNA Loc105611671 promotes the proliferation of ovarian granulosa cells and steroid hormone production upregulation of CDC42

Granulosa cells (GCs) are essential for follicular development, and long non-coding RNAs (LncRNAs) are known to support the maintenance of this process and hormone synthesis in mammals. Nevertheless, the regulatory roles of these lncRNAs within sheep follicular GCs remain largely unexplored. This study delved into the influence of a Loc105611671, on the proliferation and steroid hormone synthesis of sheep ovarian GCs and the associated target genes in vitro. Cell Counting Kit-8 (CCK-8) gain-of-function experiments indicated that overexpression of Loc105611671 significantly boosted GCs proliferation, along with estrogen (E2) and progesterone (P4) levels. Further mechanistic scrutiny revealed that Loc105611671 is primarily localized within the cytoplasm of ovarian granulosa cells and engages in molecular interplay with CDC42. This interaction results in the upregulation of CDC42 protein expression. Moreover, it was discerned that increased CDC42 levels contribute to augmented proliferation of follicular granulosa cells and the secretion of E2 and P4. Experiments involving co-transfection elucidated that the concurrent overexpression of CDC42 and Loc105611671 acted synergistically to potentiate these effects. These findings provide insights into the molecular underpinnings of fecundity in ovine species and may inform future strategies for enhancing reproductive outcomes.

WD Repeat and HMG Box DNA Binding Protein 1: An Oncoprotein at the Hub of Tumorigenesis and a Novel Therapeutic Target

WD repeat and HMG-box DNA binding protein 1 (WDHD1) is a highly conserved gene from yeast to humans. It actively participates in DNA replication, playing a crucial role in DNA damage repair and the cell cycle, contributing to centromere formation and sister chromosome segregation. Notably, several studies have implicated WDHD1 in the development and progression of diverse tumor types, including esophageal carcinoma, pulmonary carcinoma, and breast carcinoma. Additionally, the inhibitor of WDHD1 has been found to enhance radiation sensitivity, improve drug resistance, and significantly decrease tumor cell proliferation. This comprehensive review aims to provide an overview of the molecular structure, biological functions, and regulatory mechanisms of WDHD1 in tumors, thereby establishing a foundation for future investigations and potential clinical applications of WDHD1.