Effect of melatonin on ATG2B-mediated autophagy regulation in sheep granulosa cells with different FecB genotypes.

Melatonin (MLT) protects cells by reducing reactive oxygen species (ROS) levels, which are key for inducing cellular autophagy. The aim of this study was to investigate the molecular mechanisms underlying MLT regulation of autophagy in granulosa cells (GCs) with BMPR-1B homozygous (FecB BB) and wild type (FecB ++) mutations. GCs collected from small-tailed Han sheep with different FecB genotypes were typed using a TaqMan probe assay, and autophagy levels were found to be significantly higher in GCs with FecB BB than the levels in those with FecB ++. Autophagy-related 2 homolog B (ATG2B) was associated with cell autophagy and was highly expressed in GCs with the FecB BB genotype in small-tailed Han sheep. Overexpression of ATG2B in the GCs of sheep with both FecB genotypes promoted GC autophagy, and the contrary was observed after the inhibition of ATG2B expression. Subsequently, treatment of GCs with different genotypes of FecB and MLT revealed a significant decrease in cellular autophagy and an increase in ATG2B expression. Addition of MLT to GCs with inhibited ATG2B expression revealed that MLT could protect GCs by decreasing ROS levels, especially in GCs with FecB ++ genotype. In conclusion, this study determined that autophagy levels were significantly higher in sheep GCs with FecB BB genotype than the levels in those with FecB ++ genotype, which may have contributed to the difference in lambing numbers between the two FecB genotypes. Autophagy was regulated by ATG2B and was able to protect GCs by reducing the high levels of ROS produced following inhibition of ATG2B through the addition of MLT in vitro.

The mechanism of circadian clock and its influence on animal circannual rhythm.

The circadian clock exists in almost all life forms, and is an internal activity generated by organisms adapting to the daily periodic changes of the external environment. The circadian clock is regulated by the transcription-translation-negative feedback loop in the body, which can regulate the activities of tissues and organs. Its normal maintenance is important for the health, growth, and reproduction of organisms. In contrast, due to the season changes of the environment, organisms have also formed annual cycle physiological changes in their bodies, such as seasonal estrus, etc. The annual rhythm of living things is mainly affected by environmental factors such as photoperiod, and is related to gene expression, hormone content, morphological changes of cell and tissues in vivo. Melatonin is an important signal to recognize the changes of photoperiod, and the circadian clock plays an important role in the pituitary to interpret the signal of melatonin and regulate the changes of downstream signals, which plays an important guiding role in the recognition of annual changes in the environment and the generation of the body's annual rhythm. In this review, we summarize the progress of research on the mechanism of action of circadian clocks in influencing annual rhythms, by introducing the mechanisms of circadian and annual rhythms generation in insects and mammals, and in the context of annual rhythms in birds, with the aim of providing a broader range of ideas for future research on the mechanism of annual rhythms influence.

Progress on the effect of FecB mutation on BMPR1B activity and BMP/SMAD pathway in sheep.

BMPR1B is the first major gene of litter size identified in sheep. However, the molecular mechanism of the FecB mutation that increases the ovulation rate in sheep is still unclear. In recent years, it has been demonstrated that BMPR1B activity is regulated by the small molecule repressor protein FKBP1A, which acts as a key activity switch of the BMPR1B in the BMP/SMAD pathway. The FecB mutation is located close to the binding site of FKBP1A and BMPR1B. In this review, we summarize the structure of BMPR1B and FKBP1A proteins, and clarify the spatial interactive domains of the two proteins with respect to the location of the FecB mutation. Then the relationship between the FecB mutation and the degree of affinity of the two proteins are predicted. Finally, the hypothesis that FecB mutation causes change of activity in BMP/SMAD pathway by affecting the intensity of the interactions between BMPR1B and FKBP1A is proposed. This hypothesis provides a new clue to investigate the molecular mechanism of FecB mutation affecting ovulation rate and litter size in sheep.

A 1.1 Mb duplication CNV on chromosome 17 contributes to skeletal muscle development in Boer goats.

The Boer goat is one of the top meat breeds in modern animal husbandry and has attracted widespread attention for its unique growth performance. However, the genetic basis of muscle development in the Boer goat remains obscure. In this study, we identified specific structural variants in the Boer goat based on genome-wide selection signals and analyzed the basis of the molecular heredity of related candidate genes in muscle development. A total of 9 959 autosomal copy number variations (CNVs) were identified through selection signal analysis in 127 goat genomes. Specifically, we confirmed that the highest signal CNV (HSV) was a chromosomal arrangement containing an approximately 1.11 Mb (CHIR17: 60062304-61171840 bp) duplicated fragment inserted in reverse orientation and a 5 362 bp deleted region (CHIR17:60145940-60151302 bp) with overlapping genes (e.g., ARHGAP10, NR3C2, EDNRA, PRMT9, and TMEM184C). The homozygous duplicated HSV genotype (+/+) was found in 96% of Boer goats but was not detected in Eurasian goats and was only detected in 4% of indigenous African goats. The expression network of three candidate genes ( ARHGAP10, NR3C2, and EDNRA) regulating dose transcription was constructed by RNA sequencing. Results indicated that these genes were involved in the proliferation and differentiation of skeletal muscle satellite cells (SMSCs) and their overexpression significantly increased the expression of SAA3. The HSV of the Boer goat contributed to superior skeletal muscle growth via the dose effects of overlapping genes.

Expression analysis and single-nucleotide polymorphisms of SYNDIG1L and UNC13C genes associated with thoracic vertebral numbers in sheep (Ovis aries).

The objective of the current study was to analyze expression levels of synapse differentiation inducing 1-like (SYNDIG1L) and unc-13 homolog C (UNC13C) genes in different tissues, while single-nucleotide polymorphisms (SNPs) of two genes were associated with multiple thoracic vertebrae traits in both Small-tailed Han sheep (STH) and Sunite sheep (SNT). The expression levels of SYNDIG1L and UNC13C were analyzed in the brain, cerebellum, heart, liver, spleen, lung, kidney, adrenal gland, uterine horn, longissimus muscle, and abdominal adipose tissues of two sheep breeds with different thoracic vertebral number (TVN) sheep (T13 groups and T14 groups) by real-time quantitative polymerase chain reaction (RT-qPCR). Meanwhile, the polymorphisms of UNC13C gene g.52919279C > T and SYNDIG1L gene g.82573325C > A in T14 and T13 were genotyped by the Sequenom MassARRAY® SNP assay, and association analysis was performed with the TVN. The results demonstrated that UNC13C gene was extensively expressed in 11 tissues. The expression of UNC13C gene in longissimus muscle of T14 groups of STH was significantly higher than that of T13 groups ( P < 0.05 ). SYNDIG1L gene was overexpressed in brain and cerebellum tissues, and the expression level of UNC13C gene in the brain and cerebellum of T13 groups in SNT was significantly higher than that of T14 groups ( P < 0.01 ). Association analysis showed that SNPs found in the UNC13C gene had no significant effects on TVN for both two genes. The polymorphism of SYNDIG1L g.82573325C > A was significantly correlated with the TVN in both STH ( P < 0.05 ) and SNT ( P < 0.01 ). Taken together, the SYNDIG1L gene was related to thoracic vertebral development, and this variation may be potentially used as a molecular marker to select the multiple thoracic vertebrae in sheep.

The expression and mutation of BMPR1B and its association with litter size in small-tail Han sheep (Ovis aries).

Previous studies have shown that BMPR1B promotes follicular development and ovarian granulosa cell proliferation, thereby affecting ovulation in mammals. In this study, the expression and polymorphism of the BMPR1B gene associated with litter size in small-tail Han (STH) sheep were determined. The expression of BMPR1B was detected in 14 tissues of STH sheep during the follicular phase as well as in the hypothalamic-pituitary-gonadal (HPG) axis of monotocous and polytocous STH sheep during the follicular and luteal phases using quantitative polymerase chain reaction (qPCR). Sequenom MassARRAY® single nucleotide polymorphism (SNP) technology was also used to detect the polymorphism of SNPs in seven sheep breeds. Here, BMPR1B was highly expressed in hypothalamus, ovary, uterus, and oviduct tissue during the follicular phase, and BMPR1B was expressed significantly more in the hypothalamus of polytocous ewes than in monotocous ewes during both the follicular and luteal phases ( P < 0.05 ). For genotyping, we found that genotype and allele frequencies of three loci of the BMPR1B gene were extremely significantly different ( P < 0.01 ) between the monotocous and polytocous groups. Association analysis results showed that the g.29380965A > G locus had significant negative effects on the litter size of STH sheep, and the combination of g.29380965A > G and FecB (Fec - fecundity and B - Booroola; A746G) at the BMPR1B gene showed that the litter size of AG-GG, AA-GG, and GG-GG genotypes was significantly higher compared with other genotypes ( P < 0.05 ). This is the first study to find a new molecular marker affecting litter size and to systematically analyze the expression of BMPR1B in different fecundity and physiological periods of STH sheep.

Expression characteristics of pineal miRNAs at ovine different reproductive stages and the identification of miRNAs targeting the AANAT gene.

BACKGROUND: Many recent studies have shown that miRNAs play important roles in the regulation of animal reproduction, including seasonal reproduction. The pineal gland is a crucial hub in the regulation of seasonal reproduction. However, little is known about the expression characteristics of pineal miRNAs in different reproductive seasons (anestrus and breeding season). Therefore, the expression profiles and regulatory roles of ovine pineal miRNAs were investigated during different reproductive stages using Solexa sequencing technology and dual luciferase reporter assays. RESULTS: A total of 427 miRNAs were identified in the sheep pineal gland. Significant differences in miRNA expression were demonstrated between anestrus and the breeding season in terms of the frequency distributions of miRNA lengths, number of expressed miRNAs, and specifically and highly expressed miRNAs in each reproductive stage. KEGG analysis of the differentially expressed (DE) miRNAs between anestrus and the breeding season indicated that they are significantly enriched in pathways related to protein synthesis, secretion and uptake. Furthermore, transcriptome analysis revealed that many target genes of DE miRNAs in the ribosome pathway showed relatively low expression in the breeding season. On the other hand, analyses combining miRNA-gene expression data with target relationship validation in vitro implied that miR-89 may participate in the negative regulation of aralkylamine N-acetyltransferase (AANAT) mRNA expression by targeting its 3'UTR at a unique binding site. CONCLUSIONS: Our results provide new insights into the expression characteristics of sheep pineal miRNAs at different reproductive stages and into the negative regulatory effects of pineal miRNAs on AANAT mRNA expression.

Polymorphism, expression and structure analysis of key genes in the ovarian steroidogenesis pathway in sheep (Ovis aries).

BACKGROUND: Litter size is an important factor that significantly affects the development of the sheep industry. Our previous TMT proteomics analysis found that three key proteins in the ovarian steroidogenesis pathway, STAR, HSD3B1, and CYP11A1, may affect the litter size trait of Small Tail Han sheep. OBJECTIVE: The purpose of this study was to better understand the relationship between polymorphisms of these three genes and litter size. MATERIAL AND METHOD: Sequenom MassARRAY detected genetic variance of the three genes in 768 sheep. Real-time qPCR of the three genes was used to compare their expression in monotocous and polytocous sheep in relevant tissues. Finally, bioinformatics analysis predicted the protein sequences of the different SNP variants. RESULT: Association analysis showed that there was a significant difference in litter size among the genotypes at two loci of the CYP11A1 gene (p < 0.05), but no significant difference was observed in litter size among all genotypes at all loci of the STAR and HSD3B1 genes (p > 0.05). However, STAR expression was significantly different in polytocous and monotocous sheep in the pituitary (p < 0.01). Tissue-specific expression in the ovary was observed for HSD3B1 (p < 0.05), but its expression was not different between polytocous and monotocous sheep. Bioinformatics analysis showed that the g.33217408C > T mutation of CYP11A1 resulted in major changes to the secondary and tertiary structures. In contrast, gene polymorphisms in STAR and HSD3B1 had minimal impacts on their protein structures. DISCUSSION: This may explain why the CYP11A1 variant impacted litter size while the others did not. The single nucleotide polymorphism of the CYP11A1 gene would serve as a good molecular marker when breeding to increase litter size in sheep. Our study provides a basis for further revealing the function of the ovarian steroidogenesis pathway in sheep reproduction and sheep breeding.

Evolutionary relationship and population structure of domestic Bovidae animals based on MHC-linked and neutral autosomal microsatellite markers.

Major histocompatibility complex (MHC) genes are critical for disease resistance or susceptibility responsible for host-pathogen interactions determined mainly by extensive polymorphisms in the MHC genes. Here, we examined the diversity and phylogenetic pattern of MHC haplotypes reconstructed using three MHC-linked microsatellite markers in 55 populations of five Bovidae species and compared them with those based on neutral autosomal microsatellite markers (NAMs). Three-hundred-and-forty MHC haplotypes were identified in 1453 Bovidae individuals, suggesting significantly higher polymorphism and heterozygosity compared with those based on NAMs. The ambitious boundaries in population differentiation (phylogenetic network, pairwise FST and STRUCTURE analyses) within and between species assessed using the MHC haplotypes were different from those revealed by NAMs associated closely with speciation, geographical distribution, domestication and management histories. In addition, the mean FST was significantly correlated negatively with the number of observed alleles (NA), observed (HO) and expected (HE) heterozygosity and polymorphism information content (PIC) (P < 0.05) in the MHC haplotype dataset while there was no correction of the mean FST estimates (P> 0.05) between the MHC haplotype and NAMs datasets. Analysis of molecular variance (AMOVA) revealed a lower percentage of total variance (PTV) between species/groups based on the MHC-linked microsatellites than NAMs. Therefore, it was inferred that individuals within populations accumulated as many MHC variants as possible to increase their heterozygosity and thus the survival rate of their affiliated populations and species, which eventually reduced population differentiation and thereby complicated their classification and phylogenetic relationship inference. In summary, host-pathogen coevolution and heterozygote advantage, rather than demographic history, act as key driving forces shaping the MHC diversity within the populations and determining the interspecific MHC diversity.

Identification of a Goat Intersexuality-Associated Novel Variant Through Genome-Wide Resequencing and Hi-C.

Background: Polled intersex syndrome (PIS) leads to reproductive disorders in goats and exerts a heavy influence on goat breeding. Since 2001, the core variant of an 11.7 kb deletion at ~129 Mb on chromosome 1 (CHI1) has been widely used as a genetic diagnostic criterion. In 2020, a ~0.48 Mb insertion within the PIS deletion was identified by sequencing in XX intersex goats. However, the suitability of this variation for the diagnosis of intersex goats worldwide and its further molecular genetic mechanism need to be clarified. Results: The whole-genome selective sweep of intersex goats from China was performed with whole-genome next-generation sequencing technology for large sample populations and a case-control study on interbreeds. A series of candidate genes related to the goat intersexuality phenotype were found. We further confirmed that a ~0.48 Mb duplicated fragment (including ERG and KCNJ15) downstream of the ~20 Mb PIS region was reversely inserted into the PIS locus in intersex Chinese goats and was consistent with that in European Saanen and Valais black-necked goats. High-throughput chromosome conformation capture (Hi-C) technology was then used to compare the 3D structures of the PIS variant neighborhood in CHI1 between intersex and non-intersex goats. A newly found structure was validated as an intrachromosomal rearrangement. This inserted duplication changed the original spatial structure of goat CHI1 and caused the appearance of several specific loop structures in the adjacent ~20 kb downstream region of FOXL2. Conclusions: Results suggested that the novel complex PIS variant genome was sufficient as a broad-spectrum clinical diagnostic marker of XX intersexuality in goats from Europe and China. A series of private dense loop structures caused by segment insertion into the PIS deletion might affect the expression of FOXL2 or other neighboring novel candidate genes. However, these structures require further in-depth molecular biological experimental verification. In general, this study provided new insights for future research on the molecular genetic mechanism underlying female-to-male sex reversal in goats.

Expression analysis of DIO2, EYA3, KISS1 and GPR54 genes in year-round estrous and seasonally estrous rams.

The expression characteristics of the hypothalamic-pituitary-gonadal (HPG) axis-related candidate genes, DIO2, EYA3, KISS1 and GPR54, were analyzed in year-round estrous rams (small-tail Han sheep, STH) and seasonally estrous rams (Sunite sheep, SNT) using qPCR. The results were as follows: DIO2 was mainly expressed in pituitary, and KISS1 was specifically expressed in hypothalamus in the two groups. However, EYA3 and GPR54 were widely expressed in the cerebrum, cerebellum, hypothalamus, pituitary, testis, epididymis, vas deferens and adrenal gland tissues in both breeds, with significant differences in the cerebellum, hypothalamus, pituitary, testis and vas deferens tissues. We speculated that DIO2 and KISS1 may have positive roles in different regions in ram year-round estrus. Moreover, the expression patterns of EYA3 and GPR54 suggested that they may regulate the estrous mode of ram via testis and vas deferens. This is the first study to systematically analyze the expression patterns of HPG axis-related genes in rams.

Identification of lncRNAs by RNA Sequencing Analysis During in Vivo Pre-Implantation Developmental Transformation in the Goat.

Pre-implantation development is a dynamic, complex and precisely regulated process that is critical for mammalian development. There is currently no description of the role of the long noncoding RNAs (lncRNAs) during the pre-implantation stages in the goat. The in vivo transcriptomes of oocytes (n = 3) and pre-implantation stages (n=19) at seven developmental stages in the goat were analyzed by RNA sequencing (RNA-Seq). The major zygotic gene activation (ZGA) event was found to occur between the 8- and 16-cell stages in the pre-implantation stages. We identified 5,160 differentially expressed lncRNAs (DELs) in developmental stage comparisons and functional analyses of the major and minor ZGAs. Fourteen lncRNA modules were found corresponding to specific pre-implantation developmental stages by weighted gene co-expression network analysis (WGCNA). A comprehensive analysis of the lncRNAs at each developmental transition of high correlation modules was done. We also identified lncRNA-mRNA networks and hub-lncRNAs for the high correlation modules at each stage. The extensive association of lncRNA target genes with other embryonic genes suggests an important regulatory role for lncRNAs in embryonic development. These data will facilitate further exploration of the role of lncRNAs in the developmental transformation in the pre-implantation stage.

Genome-wide selection signatures analysis of litter size in Dazu black goats using single-nucleotide polymorphism.

Litter size is considered to be the most important index for estimating domestic animal productivity. The number of indigenous goats in China with higher litter sizes than those of commercial breeds in other countries may be helpful for accelerating genetic improvements in goat breeding. We performed a genome-wide selective sweep analysis of 31 Dazu black goats with extreme standard deviation in litter size within the third fetus to identify significant genomic regions and candidate genes through different analyses. The analysis identified a total of 33,917,703 variants, including 32,262,179 SNPs and 1,655,524 indels. In addition, two novel candidate genes (LRP1B and GLRB), which are related to litter size, were obtained with π, Tajima's D, πA/πB, and F ST at the individual level with a 95% threshold for each parameter. These two genes were annotated in five GO terms (localization, binding, macromolecular complex, membrane part, and membrane) and two pathways (long-term depression and neuroactive ligand-receptor interaction pathway). Regarding the result of linkage disequilibrium (LD) analysis, in LRP1B and GRID2, the high-yield Dazu black goats exhibit significantly different LD patterns from low-yield goats. Litter size variability has low heritability and is related to multiple complex factors found in domestic animals. Obtaining a clear explanation and significant signal by genome-wide selective sweep analysis with a small sample size is difficult. However, we investigated some candidate genes, particularly LRP1B and GLRB, which may provide useful information for further research.

Genetic diversity estimation of Yunnan indigenous goat breeds using microsatellite markers.

BACKGROUND: To assess the genetic diversity of seven Yunnan indigenous goat populations (Fengqing hornless goat, Mile red-bone goat, Longling goat, Ninglang black goat, Black-bone goat, Yunling black goat, and Zhaotong goat), their population structures were investigated using 20 microsatellite markers. RESULTS: The results indicated that the genetic diversity of these goats was rich. The observed heterozygosity ranged from 0.4667 ± 0.0243 to 0.5793 ± 0.0230, and the mean number of alleles ranged from 4.80 ± 1.61 and 4.80 ± 1.64 to 6.20 ± 2.93. The population structure analysis showed that these seven goat populations were separated into two clusters, consistent with the results from phylogenetic networks, pairwise differences, and STRUCTURE analyses. We speculate that this may have been caused by natural geographical isolation, human migration and economic and cultural exchanges. We suggest removing CSRD247 and ILSTS005, two loci identified to be under positive selection in the present study, from the microsatellite evaluation system of goats. CONCLUSIONS: The present study may provide a scientific basis for the conservation and utilization of Yunnan indigenous goats.

Current genetic diversity in eight local Chinese sheep populations.

China has numerous local domestic sheep breeds. In this study, the genetic diversity of eight sheep populations was estimated using 17 microsatellites. Knowledge of such diversity provides novel insight into the degree of breed protection needed and the prediction of hybrid advantage. In total, 17 microsatellites were genotyped in 186 individuals from eight populations. The mean number of alleles (± SD) ranged from 3.71 ± 1.36 in Zhaotong sheep to 11.94 ± 3.58 in small-tailed Han sheep. The observed heterozygote frequency (± SD) within a population ranged from 0.482 ± 0.025 in Zhaotong sheep to 0.664 ± 0.023 in Tibetan sheep. In addition, using pairwise difference (FST) analysis, the highest within-population diversity was observed in Tibetan sheep (πX = 12.8098) and small-tailed Han (πX = 12.67873), and the lowest diversity was observed in Zhaotong sheep (πX = 7.90337). The results for genetic divergence between populations indicated that the populations were significantly different (P < 0.05) based on the average number of pairwise differences between populations (πXY) and the corrected average pairwise differences. Both phylogenetic networks and structure analysis showed that these eight populations were separated into three clusters in accordance with their geographical habitat, except Tibetan and Hu sheep. In short, we genotyped eight local Chinese sheep populations using 17 microsatellites, and the results indicated that their current genetic diversity is decreasing and that new conservation strategies are needed. In addition, significant genetic differences between populations could be used in cross breeding.

[Comparison of different single cell whole genome amplification methods and MALBAC applications in assisted reproduction].

Single-cell whole genome amplification (WGA) is a new technology, which can amplify small amounts of DNA from single cell and obtain the high coverage whole genome DNA template for revealing cell heterogeneity. Single cell WGA methods mainly include primer extension preamplification PCR (PEP-PCR), degenerate oligonucleotide primed PCR (DOP-PCR), multiple displacement amplification (MDA), and multiple annealing and looping-based amplification cycles (MALBAC). In this review, we describe the principles and applications of different single cell genome wide amplification, and we evaluate and compare their amplification efficiency, including the coverage of genome, homogeneity, reproducibility, and detection power of single-nucleotide variants (SNV) and copy number variants (CNV). The results show that MALBAC have the highest amplification homogeneity, the lowest allelic gene knockdown rate, the best reproducibility, and the best detection effect on CNV and SNV. We also describe the applications of MALBAC in human single sperm meiosis, aneuploidy analysis, and human oocyte genome research.

Genetic diversity of the Chinese goat in the littoral zone of the Yangtze River as assessed by microsatellite and mtDNA.

The objective of this study was to assess the genetic diversity and population structure of goats in the Yangtze River region using microsatellite and mtDNA to better understand the current status of those goat genetic diversity and the effects of natural landscape in fashion of domestic animal genetic diversity. The genetic variability of 16 goat populations in the littoral zone of the Yangtze River was estimated using 21 autosomal microsatellites, which revealed high diversity and genetic population clustering with a dispersed geographical distribution. A phylogenetic analysis of the mitochondrial D-loop region (482 bp) was conducted in 494 goats from the Yangtze River region. In total, 117 SNPs were reconstructed, and 173 haplotypes were identified, 94.5% of which belonged to lineages A and B. Lineages C, D, and G had lower frequencies (5.2%), and lineage F haplotypes were undetected. Several high-frequency haplotypes were shared by different ecogeographically distributed populations, and the close phylogenetic relationships among certain low-frequency haplotypes indicated the historical exchange of genetic material among these populations. In particular, the lineage G haplotype suggests that some west Asian goat genetic material may have been transferred to China via Muslim migration.

[The molecular mechanism of sheep seasonal breeding and artificial regulatory techniques for estrus and mating in anestrus].

Seasonal breeding is an important factor limiting sheep production efficiency. Detailed analysis on the molecular mechanisms of seasonal breeding is the premise for improving estrus and mating rate of sheep during anestrus. Recent research showed that under long-photoperiod and short-photoperiod conditions, a series of changes in signaling molecules and cell morphology could be observed in ovine seasonal reproduction pathway. Based on the molecular mechanisms of seasonal reproduction, several technologies or methods for inducing estrus and mating of ewes in anestrus have been developed. In this review, photoperiod-induced changes in signaling molecules and cell morphology in pituitary and hypothalamic tissue are first summarized in terms of the molecular mechanisms and characteristics of seasonal reproduction. The application effect, advantages and disadvantages for applying these technologies for inducing estrus and mating of ewes in anestrus are then discussed, thereby providing the critical insights in identifying a new technology, which is environmentally friendly and efficient, to improve breeding rate in anestrus.

miR-27b regulates myogenic proliferation and differentiation by targeting Pax3 in goat.

This study found that miR-27 is expressed in muscle and regulates muscle proliferation and differentiation. We explored the function and regulatory mechanism of miR-27b in goat muscle proliferation and differentiation. Compared with the Boer goat, higher expression of miR-27b was observed in all of the collected muscle tissues of Anhuai goat, excluding the kidney, whereas the opposite expression pattern was observed for Pax3, which showed lower expression in Anhuai goat. Expression of miR-27b decreased gradually during the proliferation of skeletal muscle satellite cells in Anhuai goat and increased during differentiation; however, the expression pattern of Pax3 was opposite. The regulatory activity of miR-27b demonstrated that miR-27b inhibited the proliferation of skeletal muscle satellite cells, but promoted their differentiation. Moreover, function research demonstrated that Pax3 negatively regulated myogenic differentiation of goat skeletal muscle satellite cells, but accelerated their proliferation. The results of a dual-luciferase reporter analysis showed that miR-27b directly targeted the 3'-untranslated regions of Pax3 mRNA, and western blot and immunofluorescence staining analyses showed that miR-27b inhibited expression of the Pax3 protein. In goats, miR-27b can regulate myogenic proliferation and differentiation by targeting Pax3.

Cashmere growth control in Liaoning cashmere goat by ovarian carcinoma immunoreactive antigen-like protein 2 and decorin genes.

OBJECTIVE: The study investigated the biological functions and mechanisms for controlling cashmere growth of Liaoning cashmere goat by ovarian carcinoma immunoreactive antigen-like protein 2 (OCIAD2) and decorin (DCN) genes. METHODS: cDNA library of Liaoning cashmere goat was constructed in early stages. OCIAD2 and DCN genes related to cashmere growth were identified by homology analysis comparison. The expression location of OCIAD2 and DCN genes in primary and secondary hair follicles (SF) was performed using in situ hybridization. The expression of OCIAD2 and DCN genes in primary and SF was performed using real-time polymerase chain reaction (PCR). RESULTS: In situ hybridization revealed that OCIAD2 and DCN were expressed in the inner root sheath of Liaoning cashmere goat hair follicles. Real-time quantitative PCR showed that these genes were highly expressed in SF during anagen, while these genes were highly expressed in primary hair follicle in catagen phase. Melatonin (MT) inhibited the expression of OCIAD2 and promoted the expression of DCN. Insulin-like growth factors-1 (IGF-1) inhibited the expression of OCIAD2 and DCN, while fibroblast growth factors 5 (FGF5) promoted the expression of these genes. MT and IGF-1 promoted OCIAD2 synergistically, while MT and FGF5 inhibited the genes simultaneously. MT+IGF-1/MT+FGF5 inhibited DCN gene. RNAi technology showed that OCIAD2 expression was promoted, while that of DCN was inhibited. CONCLUSION: Activation of bone morphogenetic protein (BMP) signaling pathway up-regulated OCIAD2 expression and stimulated SF to control cell proliferation. DCN gene affected hair follicle morphogenesis and periodic changes by promoting transforming growth factor-ß (TGF-ß) and BMP signaling pathways. OCIAD2 and DCN genes have opposite effects on TGF-ß signaling pathway and inhibit each other to affect the hair growth.