The molecular anatomy of cashmere goat hair follicle during cytodifferentiation stage.

BACKGROUND: Cashmere, named as "soft gold", derives from the secondary hair follicles (SHFs) of cashmere goat which is vital to Northwest China's economy. The cytodifferentiation stage (E120), mirroring the complete hair follicle (HF) structure of adult goats and marking a critical phase in SHF development. Therefore, this study aims to enhance the understanding of SHF development and its impact on fiber quality, informing breeding strategies. RESULTS: From the scRNA-seq data analysis, the intricate processes and transcriptional dynamics of inner layer cell differentiation of HFs were unveiled in this study. we identified nine cell populations during cytodifferentiation and key structures such as the hair shaft and inner root sheath. And we discovered three main inner layer lineages and seven subpopulations, clarifying their roles in specialization and signaling. Pseudotime mapping analysis showed cell evolution from early stage to mature stages marked by unique gene expressions, and the intermediate stage on the differentiation of each lineage was revealed. The identification and spatial localization of specific transcription factors, such as GATA3, LEF1 and PRDM1, as well as keratin genes highlight regulatory pathways involved in HF development, which was further validated by immunofluorescence. These findings suggested the potential strategies to improve fiber quality, and the discovery of diverse cell types and their developmental molecular mechanisms, particularly in this species-specific context, offered a nuanced view of the regulatory mechanisms driving HF development in cashmere goats. CONCLUSION: Overall, these findings provide a systematic molecular atlas of skin, defining three major branches and cell states of inner layer cells of HF, and determining how the branch-specific transcription factors, keratins, and signals coordinate HF morphogenesis during cytodifferentiation stage. This research not only advances skin tissue research in goats but also holds broader implications for the understanding of HF regeneration and development across various species.

Screening and expression validation of key proteins for secondary hair follicle growth in cashmere goats based on iTRAQ quantitative proteomics technology.

Background: The growth of secondary hair follicles (SHFs) in cashmere goats has periodic changes, including telogen, anagen, and catagen, during which proteins play important roles as the executor of life activities. Results: In this study, the skin tissues of cashmere goats at three different growth stages of SHFs were collected for proteome sequencing and validation experiments. Through protein differential expression analysis and time series analysis, FKBP prolyl isomerase 10 (FKBP10) and fibrillin 2 (FBN2) were screened as the key proteins for SHF cycle growth of cashmere goats, and albumin (ALB), collagen type I alpha 1 chain (COL1A1) and elastin (ELN) were predicted to be their interacting proteins. The results of quantitative real-time PCR (qRT-PCR), western blot, and immunohistochemistry experiments showed that the mRNA and protein expression levels of FKBP10, FBN2, COL1A1, ELN and ALB were higher in anagen and lower in telogen. They were all highly expressed in the outer root sheath of SHFs in anagen. Conclusion: FKBP10, FBN2, COL1A1, ELN, and ALB can promote the growth of SHFs in cashmere goats. This study lays the foundation for analyzing the growth cycle regulatory mechanism of SHFs in cashmere goats, and provides new ideas for further improving cashmere yield and quality.

Genetic characterization of cashmere goat (Capra hircus) populations in Mongolia.

Objective: Characterization studies of the phenotypic and genetic diversity of Mongolian goats are limited, despite several goat breeds being registered in the country. This study aimed to evaluate the phenotypic and genetic diversity of 14 cashmere goat populations in Mongolia, consisting largely of identified goat breeds. Methods: Body weight, cashmere quality, and coat color were the phenotypic traits considered in this study. A linear model was used to fit body weight and cashmere traits, and least squares means (LSMs) were estimated for the region and location classes. Genetic diversity and structure were assessed using a goat 50K SNP array. Results: The studied populations exhibited greater phenotypic diversity at the regional level. A very small overall differentiation index (Fst: 0.017) was revealed by Wright's Fst and a very small overall inbreeding index (F ROH1 :0.019) was revealed based on runs of homozygosity. Genetic clustering of populations by principal components showed large variances for the two goat populations of the Russian admixture (Gobi Gurvan Saikhan and Uuliin Bor), and smaller but differentiated clusters for the remaining populations. Similar results were observed in the admixture analysis, which identified populations with the highest (Govi Gurvan Saikhan and Uuliin Bor) and lowest (Tsagaan Ovoo Khar) exotic admixtures. A genomewide association study (GWAS) of body weight and cashmere traits identified a few significant variants on chromosomes 2, 4, 5, 9, and 15, with the strongest variant for cashmere yield on chromosome 4. The GWAS on coat color yielded nine significant variants, with the strongest variants located on chromosomes 6, 13, and 18 and potential associations with KIT, ASIP, and MC1R genes. These signals were also found in other studies on coat color and patterns in goats. Conclusion: Mongolian cashmere goats showed relatively low genetic differentiation and low inbreeding levels, possibly caused by the traditional pastoral livestock management system and the practice of trading breeding bucks across provinces, along with a recent increase in the goat population. Further investigation of cashmere traits using larger samples and alternative methods may help identify the genes or genomic regions underlying cashmere quality in goats.

Transcriptome-based screening and validation of key genes for wool color in cashmere goats.

BACKGROUND: Colored wool from cashmere goats is increasingly popular among consumers, but the transcriptomic differences between coat colors are poorly understood. OBJECTIVES: This study aimed to screen for coat color regulation-associated genes in cashmere goats to ascertain their underlying molecular mechanisms. METHODS: Transcriptomic sequencing of skin tissues from black (BC), brown (YC), and white cashmere (WC) goats was performed. Immunohistochemistry and western blotting were used to validate SLC24A4 and DCT expression, two essential genes identified for coat color determination. RESULTS: We identified 6,518 differentially expressed genes (DEGs) in the BC vs. WC group (3,919 upregulated, 2,599 downregulated). Next, 5,593 DEGs were identified in the YC vs. WC group (3,629 upregulated, 1,964 downregulated). Finally, 4,538 DEGs were expressed in both groups, with 1,980 and 1,055 DEGs exclusively expressed in either group. Functions and pathways associated with hair color were enriched, including melanosomes, melanocyte migration, melanin biosynthesis processes and functions, and melanogenesis pathways. TYRP1, SLC24A4, PMEL, OCA2, and DCT were significantly upregulated in BC goat skin, while ASIP was significantly upregulated in YC skin. Additionally, KIT, POMC, SLC24A5, Wnt3a, and EDN3 were DEGs for different coat colors. Immunohistochemistry revealed SLC24A4 and DCT expression in dermal papillae, inner and outer root sheaths, and the hair follicle matrix. Western blotting showed that SLC24A4 protein levels were highest in BC goat skin. DCT protein levels were also highest in BC goat skin, albeit not significantly. CONCLUSION: These results further our understanding of coat color regulation in cashmere goats, establishing a foundation for their molecular breeding.

LncRNA018392 promotes the proliferation of Liaoning cashmere goat skin fibroblasts by upregulating CSF1R through binding to SPI1.

BACKGROUND: Liaoning cashmere goat is recognized as a valuable genetic resource breed, with restrictions on genetic outflow in China. Hair follicle development in the cashmere goat is influenced by melatonin and long non-coding RNAs (lncRNAs). However, the role of lncRNAs in facilitating melatonin-promoted cashmere growth remains poorly understood. Previous studies have identified a new lncRNA, lncRNA018392, which is involved in the melatonin-promoted proliferation of cashmere skin fibroblasts. METHOD: Flow cytometry and CCK-8 assays confirmed that silencing lncRNA018392 negates the effects of melatonin on cell proliferation, and that proliferation was reduced when the gene CSF1R, located near lncRNA018392, was inhibited. Further investigation using a dual-luciferase reporter assay showed that lncRNA018392 could positively regulate the promoter of CSF1R. RESULTS: Results from RNA-binding protein immunoprecipitation (RIP) and chromatin immunoprecipitation sequencing (ChIP-Seq) revealed that lncRNA018392 interacts with the transcription factor SPI1, with CSF1R being a downstream target gene regulated by SPI1. This interaction was confirmed by ChIP-PCR, which demonstrated SPI1's binding to CSF1R. CONCLUSIONS: This study found that the melatonin-responsive lncRNA018392 accelerates the cell cycle and promotes cell proliferation by recruiting SPI1 to upregulate the expression of the neighboring gene CSF1R. These findings provide a theoretical foundation for elucidating the molecular mechanisms of cashmere growth and for the molecular breeding of cashmere goats.

Role of Csdc2 in Regulating Secondary Hair Follicle Growth in Cashmere Goats.

Cashmere goats possess two types of hair follicles, with the secondary hair follicles producing valuable cashmere fiber used for textiles. The growth of cashmere exhibits a seasonal pattern arising from photoperiod change. Transcription factors play crucial roles during this process. The transcription factor, cold-shock domain, containing C2 (Csdc2) plays a crucial role in modulating cell proliferation and differentiation. Our preceding research indicated that the expression of Csdc2 changes periodically during anagen to telogen. However, the mechanisms of Csdc2 in regulating SHF growth remain unclear. Here, we found that the knockdown of Csdc2 inhibits the proliferation of dermal papilla cells. ChIP-Seq analysis showed that Csdc2 had a unique DNA binding motif in SHFs. Through conjoint analysis of ChIP-Seq and RNA-Seq, we revealed a total of 25 candidate target genes of Csdc2. Notably, we discovered a putative Csdc2 binding site within roundabout guidance receptor 2 (Robo2) on chromosome 1 of the goat genome. Furthermore, qRT-PCR and dual-luciferase reporter assay confirmed Csdc2's positive regulatory influence on Robo2. These findings expand the research field of hair follicle transcriptional regulatory networks, offering insights into molecular breeding strategies to enhance cashmere production in goats.

Shh Gene Regulates the Proliferation and Apoptosis of Dermal Papilla Cells to Affect Its Differential Expression in Secondary Hair Follicle Growth Cycle of Cashmere Goats.

Sonic hedgehog (Shh) is a component of the Hedgehog signaling pathway, playing an important role in regulating cell proliferation, differentiation, apoptosis, and the repair of damaged organisms. To further clarify the expression pattern of Shh gene in the secondary hair follicle growth cycle of cashmere goats and its mechanism of action on secondary hair follicle papilla cells, and improve cashmere quality, in this study, we took Inner Mongolia Albas white cashmere goats as the research objects and collected skin samples at different growth stages to obtain secondary hair follicles, detected Shh and its gene expression by RT-qPCR, Western blot, immunohistochemistry, and other techniques, while we also cultured DPCs in vitro. Shh gene overexpression and interference vectors were constructed, and the effects of Shh gene on the proliferation and apoptosis of DPCs were studied through cell transfection technology. The results showed that there are significant differences in Shh and its gene expression in the secondary hair follicle growth cycle skins of cashmere goats, with the highest expression level in anagen, followed by catagen, and the lowest expression level in telogen. Shh was mainly expressed in the inner root sheath, outer root sheath, and secondary hair follicle papilla. After the overexpression of Shh gene, the proliferation and vitality of the hair papilla cells were enhanced compared to the interference group. After Shh gene interference, the apoptosis rate of the cells increased, indicating that Shh gene can regulate downstream Ptch, Smo, and Gli2 gene expression to promote the proliferation of DPCs, and thus form its expression pattern in the secondary hair follicle growth cycle of cashmere goats.

Genome-wide association analysis of fleece traits in Northwest Xizang white cashmere goat.

Northwest Xizang White Cashmere Goat (NXWCG) is the first new breed of cashmere goat in the Xizang Autonomous Region. It has significant characteristics of extremely high fineness, gloss, and softness. Genome-wide association analysis is an effective biological method used to measure the consistency and correlation of genotype changes between two molecular markers in the genome. In addition, it can screen out the key genes affecting the complex traits of biological individuals. The aim of this study was to analyze the genetic mechanism of cashmere trait variation in NXWCG and to discover SNP locus and key genes closely related to traits such as superfine cashmere. Additionally, the key genes near the obtained significant SNPs were analyzed by gene function annotation and biological function mining. In this study, the phenotype data of the four traits (cashmere length, fiber length, cashmere diameter, and cashmere production) were collected. GGP_Goat_70K SNP chip was used for genotyping the ear tissue DNA of the experimental group. Subsequently, the association of phenotype data and genotype data was performed using Gemma-0.98.1 software. A linear mixed model was used for the association study. The results showed that four fleece traits were associated with 18 significant SNPs at the genome level and 232 SNPs at the chromosome level, through gene annotated from Capra hircus genome using assembly ARS1. A total of 107 candidate genes related to fleece traits were obtained. Combined with Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis, we can find that CLNS1A, CCSER1, RPS6KC1, PRLR, KCNRG, KCNK9, and CLYBL can be used as important candidate genes for fleece traits of NXWCG. We used Sanger sequencing and suitability chi-square test to further verify the significant loci and candidate genes screened by GWAS, and the results show that the base mutations loci on the five candidate genes, CCSER1 (snp12579, 34,449,796, A → G), RPS6KC1 (snp41503, 69,173,527, A → G), KCNRG (snp41082, 67,134,820, G → A), KCNK9 (14:78472665, 78,472,665, G → A), and CLYBL (12: 9705753, 9,705,753, C → T), significantly affect the fleece traits of NXWCG. The results provide a valuable basis for future research and contribute to a better understanding of the genetic structure variation of the goat.

Metabolomics reveals metabolites associated with hair follicle cycle in cashmere goats.

BACKGROUND: The hair follicle is a skin accessory organ that regulates hair development, and its activity varies on a regular basis. However, the significance of metabolites in the hair follicle cycle has long been unknown. RESULTS: Targeted metabolomics was used in this investigation to reveal the expression patterns of 1903 metabolites in cashmere goat skin during anagen to telogen. A statistical analysis was used to investigate the potential associations between metabolites and the hair follicle cycle. The findings revealed clear changes in the expression patterns of metabolites at various phases and in various feeding models. The majority of metabolites (primarily amino acids, nucleotides, their metabolites, and lipids) showed downregulated expression from anagen (An) to telogen (Tn), which was associated with gene expression, protein synthesis and transport, and cell structure, which reflected, to some extent, that the cells associated with hair follicle development are active in An and apoptotic in An-Tn. It is worth mentioning that the expression of vitamin D3 and 3,3',5-triiodo-L-thyronine decreased and then increased, which may be related to the shorter and longer duration of outdoor light, which may stimulate the hair follicle to transition from An to catagen (Cn). In the comparison of different hair follicle development stages (An, Cn, and Tn) or feeding modes (grazing and barn feeding), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that common differentially expressed metabolites (DEMs) (2'-deoxyadenosine, L-valine, 2'-deoxyuridine, riboflavin, cytidine, deoxyguanosine, L-tryptophan, and guanosine-5'-monophosphate) were enriched in ABC transporters. This finding suggested that this pathway may be involved in the hair follicle cycle. Among these DEMs, riboflavin is absorbed from food, and the expression of riboflavin and sugars (D-glucose and glycogen) in skin tissue under grazing was greater and lower than that during barn feeding, respectively, suggesting that eating patterns may also alter the hair follicle cycle. CONCLUSIONS: The expression patterns of metabolites such as sugars, lipids, amino acids, and nucleotides in skin tissue affect hair follicle growth, in which 2'-deoxyadenosine, L-valine, 2'-deoxyuridine, riboflavin, cytidine, deoxyguanosine, L-tryptophan, and guanosine-5'-monophosphate may regulate the hair follicle cycle by participating in ABC transporters. Feeding practices may regulate hair follicle cycles by influencing the amount of hormones and vitamins expressed in the skin of cashmere goats.

Comparison of genomic prediction methods for early growth traits of Inner Mongolia cashmere goats based on multi trait models.

Inner Mongolia cashmere goat is an excellent livestock breed formed through long-term natural selection and artificial breeding, and is currently a world-class dual-purpose breed producing cashmere and meat. Multi trait animal model is considered to significantly improve the accuracy of genetic evaluation in livestock and poultry, enabling indirect selection between traits. In this study, the pedigree, genotype, environment, and phenotypic records of early growth traits of Inner Mongolia cashmere goats were used to build multi trait animal model., Then three methods including ABLUP, GBLUP, and ssGBLUP wereused to estimate the genetic parameters and genomic breeding values of early growth traits (birth weight, weaning weight, average daily weight gain before weaning, and yearling weight). The accuracy and reliability of genomic estimated breeding value are further evaluated using the five fold cross validation method. The results showed that the heritability of birth weight estimated by three methods was 0.13-0.15, the heritability of weaning weight was 0.13-0.20, heritability of daily weight gain before weaning was 0.11-0.14, and the heritability of yearling weight was 0.09-0.14, all of which belonged to moderate to low heritability. There is a strong positive genetic correlation between weaning weight and daily weight gain before weaning, daily weight gain before weaning and yearling weight, with correlation coefficients of 0.77-0.79 and 0.56-0.67, respectively. The same pattern was found in phenotype correlation among traits. The accuracy of the estimated breeding values by ABLUP, GBLUP, and ssGBLUP methods for birth weight is 0.5047, 0.6694, and 0.7156, respectively; the weaning weight is 0.6207, 0.6456, and 0.7254, respectively; the daily weight gain before weaning was 0.6110, 0.6855, and 0.7357 respectively; and the yearling weight was 0.6209, 0.7155, and 0.7756, respectively. In summary, the early growth traits of Inner Mongolia cashmere goats belong to moderate to low heritability, and the speed of genetic improvement is relatively slow. The genetic improvement of other growth traits can be achieved through the selection of weaning weight. The ssGBLUP method has the highest accuracy and reliability in estimating genomic breeding value of early growth traits in Inner Mongolia cashmere goats, and is significantly higher than that from ABLUP method, indicating that it is the best method for genomic breeding of early growth weight in Inner Mongolia cashmere goats.

Age-Related Variations in the Population of Active Secondary Hair Follicles, Oxidative Stress and Antioxidant Parameters in Cashmere Goats.

The objective of this study was to investigate age-related changes in cashmere production and the population of active secondary hair follicles in cashmere goats across different age groups as well as to explore the association between secondary hair follicle activity and oxidative stress. A total of 104 adult Inner Mongolian ewe goats, aged between 2 and 7 years old, were randomly selected as experimental subjects. Skin samples were collected in August 2020 and cashmere samples were collected in April 2021. The cashmere fiber yield, staple length, and diameter showed age-related variations in cashmere goats aged 2 to 7 years (p < 0.05). Cashmere production was higher in goats aged 2-4 years compared to those aged 5-7 years (p < 0.05). There were no significant differences in the population of primary and secondary hair follicles among goats aged 2 to 7 years. However, the population of active secondary hair follicles varied significantly with age, with the younger group (aged 2-4 years) having a higher population than those aged 5-7 years (p < 0.05). A moderate negative correlation was observed between cashmere fiber diameter and the population of active secondary hair follicles (p < 0.05). Age-related variations in skin antioxidant capacity and oxidative damage were observed among cashmere goats aged 2 to 7 years old (p < 0.05). Goats aged 2 to 4 years exhibited higher antioxidant capacity and lower oxidative damage (p < 0.05). Interestingly, the skin's antioxidant capacity and oxidative damage exhibited significant positive and negative correlations with the population of active secondary hair follicles (p < 0.05). This study presents a novel approach to enhance the activity of secondary hair follicles and improve cashmere production performance through the regulation of oxidative stress.

LncRNA MTC-p65 Protein Mediates Skin Fibroblast Proliferation in Liaoning Cashmere Goat by Regulating the Nuclear Factor-Kappa B Signaling Pathway.

The aim of this study is to investigate the activation of NF-κB signaling pathway and the regulation of the expression of genes related to chorionic villus growth by the binding of LncRNA MTC (XLOC_005914) and p65 (transcription factor p65 [Capra hircus], XP_017898873.1). In addition, the regulation of LncRNA MTC and p65 binding on the proliferation of Liaoning Cashmere Goat skin fibroblasts is investigated. The upregulation of LncRNA MTC promoted the proliferation of skin fibroblasts, and the NF-κB signaling pathway played an important role in this process. Compared with the negative control (NC group), the expression of TNFα and NFKB2(NF-κB) genes was highly significantly up-regulated (P < 0.001), and NFKBIA(IκBɑ) genes were highly significantly down-regulated (P < 0.01) after LncRNA MTC overexpression (OE group). The expression levels of TNFα and NFκB-P-p65 proteins were upregulated in the OE group; NF-κB-p65 expression levels were upregulated in the nucleus, IκBα expression levels were downregulated in the cytoplasm, and P-IκBα expression levels were upregulated. LncRNA MTC and p65 proteins were co-localized in the cells. Meanwhile, LncRNA MTC and p65 protein showed significant nucleation in the OE group. RNA pull-down and LC-MS/MS verified that p65 protein was indeed an interacting protein of LncRNA MTC. LncRNA MTC binds to p65 protein, upregulates the expression of TNFα protein, nucleates p65 protein, and activates NF-κB signaling pathway to promote the proliferation of skin fibroblasts in Liaoning Cashmere Goat.

Genetic diversity and population structure in five Inner Mongolia cashmere goat populations using whole-genome genotyping.

OBJECTIVE: As a charismatic species, cashmere goats have rich genetic resources. In the Inner Mongolia Autonomous Region, there are three cashmere goat varieties named and approved by the state. These goats are renowned for their high cashmere production and superior cashmere quality. Therefore, it is vitally important to protect their genetic resources as they will serve as breeding material for developing new varieties in the future. METHODS: Three breeds including Inner Mongolia cashmere goats (IMCG), Hanshan White cashmere goats (HS), and Ujimqin white cashmere goats (WZMQ) were studied. IMCG were of three types: Aerbas (AEBS), Erlangshan (ELS), and Alashan (ALS). Nine DNA samples were collected for each population, and they were genomically re-sequenced to obtain high-depth data. The genetic diversity parameters of each population were estimated to determine selection intensity. Principal component analysis, phylogenetic tree construction and genetic differentiation parameter estimation were performed to determine genetic relationships among populations. RESULTS: Samples from the 45 individuals from the five goat populations were sequenced, and 30,601,671 raw single nucleotide polymorphisms (SNPs) obtained. Then, variant calling was conducted using the reference genome, and 17,214,526 SNPs were retained after quality control. Individual sequencing depth of individuals ranged from 21.13× to 46.18×, with an average of 28.5×. In the AEBS, locus polymorphism (79.28) and expected heterozygosity (0.2554) proportions were the lowest, and the homologous consistency ratio (0.1021) and average inbreeding coefficient (0.1348) were the highest, indicating that this population had strong selection intensity. Conversely, ALS and WZMQ selection intensity was relatively low. Genetic distance between HS and the other four populations was relatively high, and genetic exchange existed among the other four populations. CONCLUSION: The Inner Mongolia cashmere goat (AEBS type) population has a relatively high selection intensity and a low genetic diversity. The IMCG (ALS type) and WZMQ populations had relatively low selection intensity and high genetic diversity. The genetic distance between HS and the other four populations was relatively high, with a moderate degree of differentiation. Overall, these genetic variations provide a solid foundation for resource identification of Inner Mongolia Autonomous Region cashmere goats in the future.

Genomic Inbreeding and Runs of Homozygosity Analysis of Cashmere Goat.

Cashmere goats are valuable genetic resources which are famous worldwide for their high-quality fiber. Runs of homozygosity (ROHs) have been identified as an efficient tool to assess inbreeding level and identify related genes under selection. However, there is limited research on ROHs in cashmere goats. Therefore, we investigated the ROH pattern, assessed genomic inbreeding levels and examined the candidate genes associated with the cashmere trait using whole-genome resequencing data from 123 goats. Herein, the Inner Mongolia cashmere goat presented the lowest inbreeding coefficient of 0.0263. In total, we identified 57,224 ROHs. Seventy-four ROH islands containing 50 genes were detected. Certain identified genes were related to meat, fiber and milk production (FGF1, PTPRM, RERE, GRID2, RARA); fertility (BIRC6, ECE2, CDH23, PAK1); disease or cold resistance and adaptability (PDCD1LG2, SVIL, PRDM16, RFX4, SH3BP2); and body size and growth (TMEM63C, SYN3, SDC1, STRBP, SMG6). 135 consensus ROHs were identified, and we found candidate genes (FGF5, DVL3, NRAS, KIT) were associated with fiber length or color. These findings enhance our comprehension of inbreeding levels in cashmere goats and the genetic foundations of traits influenced by selective breeding. This research contributes significantly to the future breeding, reservation and use of cashmere goats and other goat breeds.

Stress adaptation in Tibetan cashmere goats is governed by inherent metabolic differences and manifested through variable cashmere phenotypes.

Tibetan cashmere goats are not only served as a valuable model for studying adaptation to hypoxia and high-altitude conditions but also playing a pivotal role in bolstering local economies through the provision of premium quality cashmere yarn. In this study, we performed an integration and network analysis of metabolomic, transcriptomic and proteomic to elucidate the role of differentially expressed genes, important metabolites, and relevant cellular and metabolic pathways between the fine (average 12.04 ± 0.03 µm of mean fiber diameter) and coarse cashmere (average 14.88 ± 0.05 µm of mean fber diameter) producing by Tibetan cashmere goats. We identified a distinction of 56 and 71 differential metabolites (DMs) between the F and C cashmere groups under positive and negative ion modes, respectively. The KEGG pathway enrichment analysis of these DMs highlighted numerous pathways predominantly involved in amino acid and protein metabolism, as indicated by the finding that the most impactful pathway was the mammalian target of rapamycin (mTOR) signalling pathway. In the F group, we identified a distinctive metabolic profile where amino acid metabolites including serine, histidine, asparagine, glutamic acid, arginine, valine, aspartic acid, tyrosine, and methionine were upregulated, while lysine, isoleucine, glutamine, tryptophan, and threonine were downregulated. The regulatory network and gene co-expression network revealed crucial genes, metabolites, and metabolic pathways. The integrative omics analysis revealed a high enrichment of several pathways, notably encompassing protein digestion and absorption, sphingolipid signalling, and the synaptic vesicle cycle. Within the sphere of our integrative analysis, DNMT3B was identified as a paramount gene, intricately associated with significant proteins such as HMCN1, CPB2, GNG12, and LRP1. Our present study delineated the molecular underpinnings governing the variations in cashmere characteristics by conducting comprehensive analyses across metabolomic, transcriptomic, and proteomic dimensions. This research provided newly insights into the mechanisms regulating cashmere traits and facilitated the advancement of selective breeding programs aimed at cultivating high-quality superfine Tibetan cashmere goats.

MiR-199a-5p inhibits dermal papilla cells proliferation by regulating VEGFA expression in cashmere goat.

Hair follicles undergo a renewal cycle consisting of anagen, telogen and catagen stages. MicroRNA (miRNA) plays a crucial role in this process. Recent studies have shown that miR-199a-5p, which exhibits differential expression between anagen and telogen stages in the hair follicle cycle of cashmere goats, inhibits the proliferation of various cell types, including skin keratinocytes and vascular endothelial cells. Since the proliferation of dermal papilla cells (DPCs) is a key factor in the hair follicle cycle, we utilized DPCs to investigate the function and molecular mechanism of miR-199a-5p in cashmere goats. Our functional analysis revealed that miR-199a-5p significantly suppressed cell viability and proliferation of DPCs, as evidenced by MTT, EdU and RT-qPCR methods. Subsequently, we investigated the regulatory mechanism of miR-199a-5p. Through bioinformatics analysis, a potential correlation between lnc102173187 and miR-199a-5p was predicted. However, the dual luciferase reporter assay revealed no interaction between lnc102173187 and miR-199a-5p. Further investigation using dual-luciferase reporter assay, RT-qPCR, and western blot results confirmed that VEGFA was the target gene of miR-199a-5p from. The functional experiment demonstrated that VEGFA promoted the proliferation of DPCs, and antagonized the inhibitory effect of miR-199a-5p on DPCs proliferation. Taken together, this research revealed the role of miR-199a-5p and VEGFA on the proliferation of dermal papilla cells in cashmere goat, which would enrich the theoretical basis for hair follicle development, and could also serve as a marker cofactor to play an important reference and guidance role in the breeding, improvement and optimization of cashmere goat breeds.

Effect of Fasted Live-Weight Gain during the Cashmere Non-Growing Period on Cashmere Production Performance and Secondary Hair Follicle Activity of Cashmere Goats.

The objective of this study was to investigate the effects of fasted live-weight gain during the cashmere non-growing period on cashmere production performance and secondary hair follicle activity, to provide a theoretical basis for appropriate supplementary feeding of cashmere goats. Fifty Inner Mongolian cashmere goats aged 2-4 years old were randomly selected and weighed in May and September 2019, respectively. Based on fasted live-weight gain between the two weights, the experimental ewe goats were divided into two groups: 0-5.0 kg group (n = 30) and 5.0-10.0 kg group (n = 20). Skin samples and cashmere samples were collected. Results of a Pearson correlation analysis showed that fasted live-weight gain during the cashmere non-growing period had a moderate and strong positive correlation with cashmere yield (p = 0.021) and cashmere staple length (p = 0.002), respectively, but did not correlate with cashmere diameter (p = 0.254). Compared with cashmere goats with a fasted live-weight gain of 0-5.0 kg, cashmere goats with a fasted live-weight gain of 5.0-10.0 kg had a 17.10% increase in cashmere yield (p = 0.037) and an 8.09% increase in cashmere staple length (p = 0.045), but had no significant difference in cashmere diameter (p = 0.324). Results of a Pearson correlation analysis showed that there was a strong positive correlation between fasted live-weight gain and the population of active secondary hair follicles in the skin of cashmere goats (p < 0.01). Compared with cashmere goats with a fasted live-weight gain of 0-5.0 kg, cashmere goats with a fasted live-weight gain of 5.0-10.0 kg had an increase in the population of active secondary hair follicles (p < 0.05). In conclusion, the fasted live-weight gain during the cashmere non-growing period had a significant effect on secondary hair follicle activity and cashmere production performance in cashmere goats. Since fasted live-weight gain reflects nutritional level to a certain extent, this study suggests that nutritional manipulations such as supplementary feeding during cashmere non-growing periods can increase cashmere production performance. However, specific nutritional manipulations during the cashmere non-growing period need further research to increase cashmere production performance.

Effects of Artemisia ordosica Crude Polysaccharide on Antioxidant and Immunity Response, Nutrient Digestibility, Rumen Fermentation, and Microbiota in Cashmere Goats.

The objective of this experiment was to investigate the effect of dietary supplementation with Artemisia ordosica crude polysaccharide (AOCP) on growth performance, nutrient digestibility, antioxidant and immunity capacity, rumen fermentation parameters, and the microbiota of cashmere goats. A total of 12 cashmere goats (2 years old) with similar weight (38.03 ± 2.42 kg of BW ± SD) were randomly divided into two dietary treatments with six replicates. The treatments were as follows: (1) control (CON, basal diet); and (2) AOCP treatment (AOCP, basal diet with 0.3% AOCP). Pre-feeding was conducted for 7 days, followed by an experimental period of 21 days. The results showed that the ADG; feed/gain (F/G); and the digestibility of DM, CP, and ADF of cashmere goats in the AOCP group were greater than in the CON group (p < 0.05). Still, there was no significant effect on the digestibility of EE, NDF, Ca, and P (p > 0.05). Compared to the CON group, AOCP increased BCP, propionate, butyrate, isobutyrate, valerate, isovalerate, and TVFA concentrations (p < 0.05), but it reduced the protozoa numbers of acetate and A/P (p < 0.05). The serum CAT, GSH-Px, T-SOD, 1L-6, and NO levels were higher in AOCP than in the CON group (p < 0.05). The addition of AOCP increased the Sobs and Ace estimators (p < 0.05) and reduced the Simpson estimator in the ruminal fluid compared to the CON group (p < 0.05). Additionally, the AOCP group increased the colonization of beneficial bacteria by positively influencing GSH-Px and IL-6 (norank_f__F082, unclassified_p__Firmicutes), as well as bacteria negatively associated with F/G (norank_f__norank_o__Bacteroidales, unclassified_p__Firmicutes, and norank_f__F082). It decreased the colonization of potential pathogenic bacteria (Aeromonas and Escherichia-Shigella) (p < 0.05) compared to the CON group. In conclusion, 0.3% AOCP improves the growth performance, nutrient digestibility, antioxidant status, immune function, rumen fermentation, and microflora of cashmere goats.

Multi-omics analysis of functional substances and expression verification in cashmere fineness.

BACKGROUND: Numerous factors influence the growth and development of cashmere. Existing research on cashmere has predominantly emphasized a single omics level. Integrating multi-omics analyses can offer a more comprehensive understanding by encompassing the entire spectrum. This study more accurately and comprehensively identified the key factors influencing cashmere fineness using multi-omics analysis. METHODS: This study used skin tissues of coarse cashmere type (CT_LCG) and fine cashmere type Liaoning cashmere goats (FT_LCG) for the analysis. This study employed an integrated approach involving transcriptomics, translatomics, proteomics, and metabolomics to identify substances associated with cashmere fineness. The findings were validated using parallel reaction monitoring (PRM) and multiple reaction monitoring (MRM) techniques. RESULTS: The GO functional enrichment analysis identified three common terms: multicellular organismal process, immune system process, and extracellular region. Furthermore, the KEGG enrichment analysis uncovered the involvement of the arachidonic acid metabolic pathway. Protein expression trends were verified using PRM technology. The expression trends of KRT79, as confirmed by PRM, were consistent with those observed in TMT proteomics and exhibited a positive regulatory effect on cashmere fineness. Metabolite expression trends were confirmed using MRM technology. The expression trends of 9 out of 15 validated metabolites were in agreement with those identified in the non-targeted metabolomics analysis. CONCLUSIONS: This study employed multi-omics analysis to identify key regulators of cashmere fineness, including PLA2G12A, KRT79, and prostaglandin B2. The findings of this study offer valuable data and establish a theoretical foundation for conducting comprehensive investigations into the molecular regulatory mechanisms and functional aspects of cashmere fineness.

Regulation of cashmere fineness traits by noncoding RNA in Jiangnan cashmere goats.

BACKGROUND: Cashmere has long been used as the raw material for wool textiles. The diameter of the cashmere fibre determines its quality and economic value. However, the regulatory role of noncoding RNAs (ncRNAs) in cashmere fineness remains unclear, especially regarding the interaction between ncRNAs and coding RNAs. RESULTS: Transcriptome sequencing was used to identify the expression profiles of long noncoding RNAs (lncRNAs), circular RNAs (circRNAs) and microRNAs (miRNAs) in the skin tissues of Jiangnan cashmere goats with different cashmere fineness levels. Integration analysis of ncRNA and coding RNA was performed in combination with previous research results. The results showed that 16,437 lncRNAs, 2234 circRNAs, and 1322 miRNAs were identified in 8 skin samples of cashmere goats. A total of 403 differentially expressed (DE) lncRNAs, 62 DE circRNAs and 30 DE miRNAs were identified in the skin tissues of the fine groups (Fe) and coarse groups (Ce). We predicted the target gene of DE lncRNA, the target gene of DE miRNA and the host gene of DE circRNA. Based on functional annotation and enrichment analysis of target genes, we found that DE lncRNAs could be involved in regulating the fineness traits of cashmere. The most potential lncRNAs were MSTRG.42054.1, MSTRG.18602.3, and MSTRG.2199.13. CONCLUSIONS: The data from this study enriched the cashmere goat noncoding RNA database and helped to supplement the annotation of the goat genome. The results provided a new direction for the breeding of cashmere characters.