An Integrated Analysis of Cashmere Fineness lncRNAs in Cashmere Goats

Knockdown of miR-361-5p promotes the induced activation of SHF-stem cells through FOXM1 mediated Wnt/β-catenin pathway in cashmere goats

The inducing activation event of secondary hair follicle (SHF)-stem cells is considered a key biological process in the SHF regeneration, and the morphogenesis of cashmere fiber in cashmere goats. The miR-361-5p was essentially implicated in the induced activation of SHF-stem cells of cashmere goats, but its functional mechanisms are unclear. Here, we confirmed miR-361-5p was significantly downregulated in anagen SHF bugle of cashmere goats compared with that at telogen, and miR-361-5p expression was significantly lower in SHF-stem cells after activation than its counterpart before activation. Further, we found that miR-361-5p could negatively regulate the induced activation event of SHF-stem cells in cashmere goats. Mechanistically, through dual-luciferase reporter assays, miR-361-5p specifically bound with FOXM1 mRNA in SHF-stem cells of cashmere goats and negatively regulated the expression of FOXM1 gene. Also, through overexpression/knockdown analysis of FOXM1 gene, our results indicated that FOXM1 upregulated the expression of Wnt/β-catenin pathway related genes in SHF-stem cells. Moreover, based on TOP/FOP-flash Wnt report assays, the knockdown of miR-361-5p promotes the Wnt/β-catenin pathway activation through upregulating the FOXM1 expression in SHF-stem cells. Finally, we demonstrated that miR-361-5p negatively regulated the induced activation of SHF-stem cells through FOXM1 mediated Wnt/β-catenin pathway in cashmere goats.

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.

CeRNA regulates network and expression and SNP effect on NFKBIA of cashmere fineness

In this study, a total of 1140 Liaoning Cashmere Goats (LCG) were genotyped for single nucleotide polymorphism (SNP) of NFKBIA gene. There are 15 SNPs and 7 genotypes have been found, and G1547A (GG) genotype has been associated with cashmere fineness and cashmere yield. An integrated ceRNA regulatory network of NFKBIA gene was made. To prove NFKBIA and these non-coding RNAs (ncRNAs) may be related to cashmere fineness, we performed qPCR on these ncRNA in LCG coarse type skin (CT-LCG) and LCG fine type skin (FT-LCG). The result of qPCR showed lncRNA XLOC_011060 and ciRNA452 are at high expression level in CT-LCG, all miRNAs appear high expressed in FT-LCG, and mir-93 was the most significant difference between CT-LCG and FT-LCG. In addition, five miRNAs were selected for qPCR in different genotypes. The qPCR results showed that mir-93 might negatively regulate cashmere fineness and mir-17-5p may play a positive role in regulating cashmere fineness of individuals with G1355A (AG) genotype. These results demonstrated that NFKBIA gene is associated with cashmere fineness of LCG and G1547A (GG) genotype is the preferred marker genotype for cashmere fineness.

High-throughput analysis of lncRNA in cows with naturally infected Staphylococcus aureus mammary gland

LncRNA (long non-coding RNA) is an RNA molecule with a length between 200 and 100,000 nt. It does not encode proteins and is involved in a variety of intracellular processes, becoming a research hotspot of genetics. To identify key lncRNAs associated with dairy mastitis, we collected mammary epithelial tissue samples of Normal disease-free Holstein cows (HCN) and unhealthy Holstein cows with Staphylococcus aureus (HCU) and performed RNA sequencing (RNA-seq) on the samples. A total of 270 differentially expressed lncRNAs and 500 differentially expressed mRNAs were identified by high-throughput sequencing and bioinformatics analysis. Furthermore, Hydrolase activity is the most enriched in GO, and ErbB signaling pathway is significantly enriched in KEGG. In addition, through qPCR validation of 5 candidate lncRNAs in HCN and HCU, four differentially expressed lncRNAs MSTRG.498, MSTRG57.1, MSTRG.41.1 and MSTRG 124.1 were confirmed to have significant differentially expressed in cow mastitis. Also, lncRNA MSTRG.498 and its target gene, SMC4, might directly or indirectly play a role in cow mastitis. The regulatory network of lncRNA-miRNA-mRNA has been inferred from a bioinformatics perspective, which may assist understand the underlying molecular mechanism of lncRNAs involved in regulating mastitis in cows. Our findings will provide meaningful resources for further research on the regulatory function of lncRNAs in cow mastitis.

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.

RNA-Seq Reveals the Roles of Long Non-Coding RNAs (lncRNAs) in Cashmere Fiber Production Performance of Cashmere Goats in China

Long non-coding RNAs (lncRNAs) are a kind of non-coding RNA being >200 nucleotides in length, and they are found to participate in hair follicle growth and development and wool fiber traits regulation. However, there are limited studies reporting the role of lncRNAs in cashmere fiber production in cashmere goats. In this study, Liaoning cashmere (LC) goats (n = 6) and Ziwuling black (ZB) goats (n = 6) with remarkable divergences in cashmere yield, cashmere fiber diameter, and cashmere color were selected for the construction of expression profiles of lncRNAs in skin tissue using RNA sequencing (RNA-seq). According to our previous report about the expression profiles of mRNAs originated from the same skin tissue as those used in the study, the cis and trans target genes of differentially expressed lncRNAs between the two caprine breeds were screened, resulting in a lncRNA-mRNA network. A total of 129 lncRNAs were differentially expressed in caprine skin tissue samples between LC goats and ZB goats. The presence of 2 cis target genes and 48 trans target genes for the differentially expressed lncRNAs resulted in 2 lncRNA-cis target gene pairs and 93 lncRNA-trans target gene pairs. The target genes concentrated on signaling pathways that were related to fiber follicle development, cashmere fiber diameter, and cashmere fiber color, including PPAR signaling pathway, metabolic pathways, fatty acid metabolism, fatty acid biosynthesis, tyrosine metabolism, and melanogenesis. A lncRNA-mRNA network revealed 22 lncRNA-trans target gene pairs for seven differentially expressed lncRNAs selected, of which 13 trans target genes contributed to regulation of cashmere fiber diameter, while nine trans target genes were responsible for cashmere fiber color. This study brings a clear explanation about the influences of lncRNAs over cashmere fiber traits in cashmere goats.

Correlation analysis of four KRTAP gene polymorphisms and cashmere fiber diameters in two cashmere goat breeds

Fiber diameter, a quantitative trait, is controlled by minor effect polygenes. Keratin-associated proteins (KRTAPs) are an important part of hair, and their rich polymorphisms facilitate the mining of cashmere trait molecular markers. In this study, Jiangnan and Tibetan cashmere goats were taken as the research object; multiplex PCR and exome sequencing technology were used to identify the exon regional polymorphisms of cashmere goats KRTAP15-1, KRTAP13.1, KRTAP27-1, and KRTAP24-1. The effects of mutation sites on the fiber diameter of cashmere were analyzed by least square method. The results showed that there were 28 mutation sites in the four KRTAP genes in Jiangnan cashmere goats and Tibetan cashmere goat populations. Among them, the KRTAP13.1, KRTAP27-1, and KRTAP24-1 gene polymorphisms were found to be significantly related to the fiber diameter of Jiangnan cashmere goats. The exploration of molecular markers in this study will help to improve the fiber diameter of the down, while the identification of gene polymorphisms will provide original data for the utilization and protection of germplasm resources of cashmere goats.

Identification of the key proteins associated with different hair types in sheep and goats

Animal-derived fiber has the characteristics of being light, soft, strong, elastic and a good thermal insulator, and it is widely used in many industries and traditional products, so it plays an important role in the economy of some countries. Variations in phenotypes of wool fibers among different species and breeds are important for industry. We found that the mean fiber diameter of cashmere was significantly smaller than that of sheep wool (p < 0.01), and sheep wool was significantly smaller than goat wool (p < 0.01). Compared with traditional proteomics technology, we analyzed cashmere, guard hair, and wool by Laber-free proteomics technology and detected 159, 204, and 70 proteins, respectively. Through the sequential windowed acquisition of all theoretical fragmentations (SWATH), 41 and 54 differentially expressed proteins were successfully detected in the cashmere vs. wool group and guard hair vs. wool group. Protein‒protein interaction network analysis of differentially expressed proteins revealed many strong interactions related to KRT85, KRTAP15-1 and KRTAP3-1. The final analysis showed that the proportion of KRT85, KRTAP15-1 and KRTAP3-1 might be the key to the difference in fiber diameter and could be used as a potential molecular marker for distinguishing different fiber types.

DNA Methylation Mediates lncRNA2919 Regulation of Hair Follicle Regeneration

Hair follicles (HFs) are organs that periodically regenerate during the growth and development of mammals. Long non-coding RNAs (lncRNAs) are non-coding RNAs with crucial roles in many biological processes. Our previous study identified that lncRNA2919 is highly expressed in catagen during the HF cycle. In this study, the in vivo rabbit model was established using intradermal injection of adenovirus-mediated lncRNA2919. The results showed that lncRNA2919 decreased HF depth and density and contributed to HF regrowth, thereby indicating that lncRNA2919 plays a negative role in HF regeneration. Moreover, methylation levels of the lncRNA2919 promoter at different HF cycle stages were detected through bisulfite sequencing. The key CpG site that negatively correlates with lncRNA2919 expression during the HF cycle was identified. 5-Aza-dc-induced demethylation upregulated lncRNA2919 expression, and the core promoter region of lncRNA2919 was verified on the basis of luciferase activity. Furthermore, we found that DNA methylation could prevent the binding of EGR1 to the lncRNA2919 promoter region, thereby affecting the transcriptional expression of lncRNA2919. Collectively, DNA methylation inhibits the transcriptional expression of lncRNA2919, which plays a vital role in the HF cycle and HF regrowth. These findings contribute to the basic theory of epigenetics in HF biology and provide references for further research in HF disease treatment and animal wool production.

lncRNA2919 Suppresses Rabbit Dermal Papilla Cell Proliferation via trans-Regulatory Actions

Hair follicles (HFs) are complex organs that grow cyclically during mammals' growth and development. Long non-coding RNAs (lncRNAs) cannot be translated into proteins and play crucial roles in many biological processes. In our previous study, candidate lncRNAs associated with HF cyclic regeneration were screened, and we identified that the novel lncRNA, lncRNA2919, was significantly expressed during catagen. Here, we identified that lncRNA2919 has no coding potentiality and is highly expressed in the cell nucleus, and downregulates HF growth and development-related genes, inhibits cell proliferation, and promotes cell apoptosis in rabbit dermal papilla cells. lncRNA2919 recruits STAT1 to form a compound. As a key transcription factor, STAT1 regulates the transcriptional expression of KRTAP11-1. Our study revealed that lncRNA2919 is involved in HF cyclic regeneration through the trans-regulatory lncRNA2919-STAT1-KRTAP11-1 axis. This study elucidates the mechanism through which lncRNA2919 regulates HF growth and development and the role of lncRNA2919 as a new therapeutic target in animal wool production and human hair-related disease treatment.

Integrated analysis of lncRNAs and mRNAs by RNA-Seq in secondary hair follicle development and cycling (anagen, catagen and telogen) of Jiangnan cashmere goat (Capra hircus)

BACKGROUND

Among the world's finest natural fiber composites is derived from the secondary hair follicles (SHFs) of cashmere goats yield one of the world's best natural fibres. Their development and cycling are characterized by photoperiodism with diverse, well-orchestrated stimulatory and inhibitory signals. Long non-coding RNA (lncRNAs) and mRNAs play important roles in hair follicle (HF) development. However, not many studies have explored their specific functions in cashmere development and cycling. This study detected mRNAs and lncRNAs with their candidate genes and related pathways in SHF development and cycling of cashmere goat. We utilized RNA sequencing (RNA-Seq) and bioinformatics analysis on lncRNA and mRNA expressions in goat hair follicles to discover candidate genes and metabolic pathways that could affect development and cycling (anagen, catagen, and telogen).

RESULTS

We identified 228 differentially expressed (DE) mRNAs and 256 DE lncRNA. For mRNAs, catagen and anagen had 16 upregulated and 35 downregulated DEGs, catagen and telogen had 18 upregulated and 9 downregulated DEGs and telogen and anagen had 52 upregulated and 98 downregulated DEGs. LncRNA witnessed 22 upregulated and 39 downregulated DEGs for catagen and anagen, 36 upregulated and 29 downregulated DEGs for catagen and telogen as well as 66 upregulated and 97 downregulated DEGs for telogen and anagen. Several key genes, including MSTRG.5451.2, MSTRG.45465.3, MSTRG.11609.2, CHST1, SH3BP4, CDKN1A, GAREM1, GSK-3β, DEFB103A KRTAP9-2, YAP1, S100A7A, FA2H, LOC102190037, LOC102179090, LOC102173866, KRT2, KRT39, FAM167A, FAT4 and EGFL6 were shown to be potentially important in hair follicle development and cycling. They were related to, WNT/β-catenin, mTORC1, ERK/MAPK, Hedgehog, TGFβ, NFkB/p38MAPK, caspase-1, and interleukin (IL)-1a signaling pathways.

CONCLUSION

This work adds to existing understanding of the regulation of HF development and cycling in cashmere goats via lncRNAs and mRNAs. It also serves as theoretical foundation for future SHF research in cashmere goats.

Proteomic analysis of coarse and fine skin tissues of Liaoning cashmere goat

Proteomics is the study of all proteins expressed by a cell or even an organism. However, knowledge of proteins that regulate the fineness of cashmere is limited. Liaoning cashmere goat (LCG) is a valuable genetic resource of China. The skin samples of Liaoning cashmere goats during the growing period were collected, performed tandem mass tag (TMT) method, and identified 117 differentially expressed proteins in CT_LCG (course type) and FT_LCG (fine type). To verify proteins differentially expressed in LCG, we performed PRM validation on three candidate proteins (ALB, SDC1, and ITGB4) in CT-LCG and FT-LCG. Furthermore, primary metabolic process and lysosome are most enriched in the GO and KEGG pathways, respectively. In addition, we also derived a protein-protein interaction (PPI) regulatory network from the perspective of bioinformatics. This study sought to elucidate the molecular mechanism of differential proteins regulating cashmere fineness of Liaoning cashmere goats by using TMT quantitative proteomics analysis. Differentially expressed proteins ALB and SDC1 may regulate cashmere fineness; ITGB4 can become a promising protein for further study. They can be used as key proteins to lay a foundation for studying cashmere fineness of Liaoning cashmere goats.

Transcriptomics analysis of cashmere fineness functional genes

Liaoning cashmere goat (LCG) is a famous cashmere goat breed in China. Cashmere fineness, as an important index to evaluate cashmere quality, is also one of the problems to be improved for Liaoning cashmere goats. Transcriptome studies all mRNA transcribed by a specific tissue or cell in a certain period. It is a key link in the study of gene expression regulation. It plays an important role in the analysis of biological growth and disease. Transcriptome is spatio-temporal specific, that is, gene expression varies in different tissues or at different times. Three coarser and three fine LCG skin samples were sequenced by RNA-seq technology, and a total of 427 differentially expressed genes were obtained, including 291 up-regulated genes and 136 down-regulated genes. In the experiment, we screened out 16 genes that had significant differences in the expression of coarse and fine cashmere of Liaoning cashmere goats, so it was inferred that these 16 genes might have regulatory effects on cashmere fineness. Moreover, GO gene set enrichment analysis revealed that differential genes mainly consist of immune response, MHC protein complex, Heme binding and other pathways. KEGG analysis showed that transplant-versus-host disease and allograft rejection were the main pathways of differential genes.

Selection of Cashmere Fineness Functional Genes by Translatomics

Cashmere fineness is an important index to evaluate cashmere quality. Liaoning Cashmere Goat (LCG) has a large cashmere production and long cashmere fiber, but its fineness is not ideal. Therefore, it is important to find genes involved in cashmere fineness that can be used in future endeavors aiming to improve this phenotype. With the continuous advancement of research, the regulation of cashmere fineness has made new developments through high-throughput sequencing and genome-wide association analysis. It has been found that translatomics can identify genes associated with phenotypic traits. Through translatomic analysis, the skin tissue of LCG sample groups differing in cashmere fineness was sequenced by Ribo-seq. With these data, we identified 529 differentially expressed genes between the sample groups among the 27197 expressed genes. From these, 343 genes were upregulated in the fine LCG group in relation to the coarse LCG group, and 186 were downregulated in the same relationship. Through GO enrichment analysis and KEGG enrichment analysis of differential genes, the biological functions and pathways of differential genes can be found. In the GO enrichment analysis, 491 genes were significantly enriched, and the functional region was mainly in the extracellular region. In the KEGG enrichment analysis, the enrichment of the human papillomavirus infection pathway was seen the most. We found that the COL6A5 gene may affect cashmere fineness.

Characterization of XR_311113.2 as a MicroRNA Sponge for Pre-ovulatory Ovarian Follicles of Goats via Long Noncoding RNA Profile and Bioinformatics Analysis

Long noncoding RNAs (lncRNAs) were identified recently as a large class of noncoding RNAs (ncRNAs) with a length ≥200 base pairs (bp). The function and mechanism of lncRNAs have been reported in a growing number of species and tissues. In contrast, the regulatory mechanism of lncRNAs in the goat reproductive system has rarely been reported. In the present study, we sequenced and analyzed the lncRNAs using bioinformatics to identify their expression profiles. As a result, 895 lncRNAs were predicted in the pre-ovulatory ovarian follicles of goats. Eighty-eight lncRNAs were differentially expressed in the Macheng black goat when compared with Boer goat. In addition, the lncRNA XR_311113.2 acted as a sponge of chi-miR-424-5p, as assessed via a luciferase activity assay. Taken together, our findings demonstrate that lncRNAs have potential effects in the ovarian follicles of goats and may represent a promising new research field to understand follicular development.

Single-Cell Sequencing Reveals Differential Cell Types in Skin Tissues of Liaoning Cashmere Goats and Key Genes Related Potentially to the Fineness of Cashmere Fiber

Cashmere fineness is one of the important factors determining cashmere quality; however, our understanding of the regulation of cashmere fineness at the cellular level is limited. Here, we used single-cell RNA sequencing and computational models to identify 13 skin cell types in Liaoning cashmere goats. We also analyzed the molecular changes in the development process by cell trajectory analysis and revealed the maturation process in the gene expression profile in Liaoning cashmere goats. Weighted gene co-expression network analysis explored hub genes in cell clusters related to cashmere formation. Secondary hair follicle dermal papilla cells (SDPCs) play an important role in the growth and density of cashmere. ACTA2, a marker gene of SDPCs, was selected for immunofluorescence (IF) and Western blot (WB) verification. Our results indicate that ACTA2 is mainly expressed in SDPCs, and WB results show different expression levels. COL1A1 is a highly expressed gene in SDPCs, which was verified by IF and WB. We then selected CXCL8 of SDPCs to verify and prove the differential expression in the coarse and fine types of Liaoning cashmere goats. Therefore, the CXCL8 gene may regulate cashmere fineness. These genes may be involved in regulating the fineness of cashmere in goat SDPCs; our research provides new insights into the mechanism of cashmere growth and fineness regulation by cells.

Screening of cashmere fineness-related genes and their ceRNA network construction in cashmere goats

Competitive endogenous RNA (ceRNA) is a transcript that can be mutually regulated at the post-transcriptional level by competing shared miRNAs. The ceRNA network connects the function of protein-encoded mRNA with the function of non-coding RNA, such as microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA). However, compared with the ceRNA, the identification and combined analysis of lncRNAs, mRNAs, miRNAs, and circRNAs in the cashmere fineness have not been completed. Using RNA-seq technology, we first identified the miRNAs presented in Liaoning Cashmere Goat (LCG) skin, and then analyzed the mRNAs, lncRNAs, circRNAs expressed in LCG and Inner Mongolia cashmere goat (MCG) skin. As a result, 464 known and 45 new miRNAs were identified in LCG skin. In LCG and MCG skin, 1222 differentially expressed mRNAs were identified, 170 differentially expressed lncRNAs and 32 differentially expressed circRNAs were obtained. Then, qRT-PCR was used to confirm further the representative lncRNAs, mRNAs, circRNAs and miRNAs. In addition, miRanda predicted the relationships of ceRNA regulatory network among lncRNAs, circRNAs, miRNAs and mRNAs, the potential regulatory effects were investigated by Go and KEGG analysis. Through the screening and analysis of the results, the ceRNA network regulating cashmere fineness was constructed. LncRNA MSTRG14109.1 and circRNA452 were competed with miRNA-2330 to regulated the expression of TCHH, KRT35 and JUNB, which may provide a potential basis for further research on the process of regulating the cashmere fineness.

The Roles of Non-coding RNA in the Development and Regeneration of Hair Follicles: Current Status and Further Perspectives

Alopecia is a common problem that affects almost every age group and is considered to be an issue for cosmetic or psychiatric reasons. The loss of hair follicles (HFs) and hair caused by alopecia impairs self-esteem, thermoregulation, tactile sensation and protection from ultraviolet light. One strategy to solve this problem is HF regeneration. Many signalling pathways and molecules participate in the morphology and regeneration of HF, such as Wnt/β-catenin, Sonic hedgehog, bone morphogenetic protein and Notch. Non-coding RNAs (ncRNAs), especially microRNAs and long ncRNAs, have significant modulatory roles in HF development and regeneration via regulation of these signalling pathways. This review provides a comprehensive overview of the status and future prospects of ncRNAs in HF regeneration and could prompt novel ncRNA-based therapeutic strategies.

CircRNA-1967 participates in the differentiation of goat SHF-SCs into hair follicle lineage by sponging miR-93-3p to enhance LEF1 expression

Circular RNAs (circRNAs), a novel class of non-coding RNAs, can interact with miRNAs through a sequence-driven sponge mechanism, thereby regulating the expression of their downstream target genes. CircRNA-1967 was found in secondary hair follicles (SHFs) of cashmere goats, but its functions are not clear. Here, we showed that both circRNA-1967 and its host gene BNC2 had significantly higher expression in SHF bulge at anagen than those at telogen of cashmere goats. Also, circRNA-1967 participates in the differentiation of SHF stem cells (SHF-SCs) into hair follicle lineage in cashmere goats. RNA pull-down assay verified that circRNA-1967 interacts with miR-93-3p. We also indicated that circRNA-1967 promoted LEF1 expression in SHF-SCs of cashmere goats. By dual-luciferase reporter analysis, we found that circRNA-1967 up-regulated LEF1 expression through the miR-93-3p-mediated pathway. The results from this study demonstrated that circRNA-1967 participated in the differentiation of goat SHF-SCs into hair follicle lineage by sponging miR-93-3p to enhance LEF1 expression. Our founding might constitute a novel pathway for revealing the potential mechanism of the differentiation of SHF-SCs into hair follicle lineage in cashmere goats. Also, these results provided a valuable basis for further enhancing the intrinsic regeneration of cashmere goat SHFs with the formation and growth of cashmere fibers.

Integrated analysis of lncRNA and mRNA reveals novel insights into cashmere fineness in Tibetan cashmere goats

Tibetan cashmere goats are famous for producing the finest, softest and lightest cashmere fiber in China. The growth and development of skin are closely related to fineness and are the key factors affecting the quality of cashmere. To investigate the specific role of long noncoding RNAs (lncRNAs) and messenger RNAs (mRNAs) in regulating cashmere fineness of Tibetan Cashmere goats in the anagen phase, we conducted high-throughput RNA sequencing of fine-type and coarse-type skin tissues. We identified 2,059 lncRNA candidates (1,589 lncRNAs annotated, 470 lncRNAs novel), and 80 differentially expressed (DE) lncRNAs and their potential targets were predicted. We also identified 384 DE messenger RNAs (mRNAs) out of 29,119 mRNAs. Several key genes in KRT26, KRT28, KRT39, IFT88, JAK3, NOTCH2 and NOTCH3 and a series of lncRNAs, including ENSCHIT00000009853, MSTRG.16794.17, MSTRG.17532.2, were shown to be potentially important for regulating cashmere fineness. GO and KEGG enrichment analyses of DE mRNAs and DE lncRNAs targets significantly enriched in positive regulation of the canonical Wnt signaling pathway, regulation of protein processing and metabolism processes. The mRNA-mRNA and lncRNA-mRNA regulatory networks further revealed potential transcripts involved in cashmere fineness. We further validated the expression patterns of DE mRNAs and DE lncRNAs by quantitative real-time PCR (qRT-PCR), and the results were consistent with the sequencing data. This study will shed new light on selective cashmere goat breeding, and these lncRNAs and mRNAs that were found to be enriched in Capra hircus RNA database.

Genetic Signatures of Selection for Cashmere Traits in Chinese Goats

Simple Summary

Cashmere goats are a unique husbandry resource in China. These goats are well known for producing the highest cashmere yield and best fiber quality in the world. Although cashmere is highly valued and also known as “fiber gem” and “soft gold”, few studies have examined the genetic basis of cashmere traits in cashmere goats. Here, we identified selection signals by comparing Fst and XP-EHH (the cross population extend haplotype homozygosity test) of a non-cashmere breed (Huanghuai goat) with those of two cashmere breeds (Inner Mongolia and Liaoning cashmere goats). Two genes (WNT10A and CSN3) were potentially associated with cashmere traits. This information may be valuable for studying the genetic uniqueness of cashmere goats and elucidating the mechanisms underlying cashmere traits in cashmere goats.

Abstract

Inner Mongolia and Liaoning cashmere goats in China are well-known for their cashmere quality and yield. Thus, they are great models for identifying genomic regions associated with cashmere traits. Herein, 53 Inner Mongolia cashmere goats, Liaoning cashmere goats and Huanghuai goats were genotyped, and 53,347 single-nucleotide polymorphisms (SNPs) were produced using the Illumina Caprine 50K SNP chip. Additionally, we identified some positively selected SNPs by analyzing Fst and XP-EHH. The top 5% of SNPs had selection signatures. After gene annotation, 222 and 173 candidate genes were identified in Inner Mongolia and Liaoning cashmere goats, respectively. Several genes were related to hair follicle development, such as TRPS1, WDR74, LRRC14, SPTLC3, IGF1R, PADI2, FOXP1, WNT10A and CSN3. Gene enrichment analysis of these cashmere trait-associated genes related 67 enriched signaling pathways that mainly participate in hair follicle development and stem cell pluripotency regulation. Furthermore, we identified 20 overlapping genes that were selected in both cashmere goat breeds. Among these overlapping genes, WNT10A and CSN3, which are associated with hair follicle development, are potentially involved in cashmere production. These findings may improve molecular breeding of cashmere goats in the future.

LncRNA-599547 contributes the inductive property of dermal papilla cells in cashmere goat through miR-15b-5p/Wnt10b axis

The lncRNA-599547 (619-nt in length) is identified in secondary hair follicle (SHF) of cashmere goat, but its functional roles in regulating the inductive property of dermal papilla cells (DPCs) remains unknown. We found that lncRNA-599547 had significantly higher expression in dermal papilla of cashmere goat SHF at anagen than its counterpart at telogen. The overexpression of lncRNA-599547 led to a significant increase of ALP and LEF1 expression in DPCs (p < 0.05), whereas, the siLncRNA-1 mediated silencing of lncRNA-599547 significantly down-regulated the expression of ALP and LEF1 in DPCs (p < 0.05). Based on biotin-labeled RNA pull-down assay, we found that lncRNA-599547 directly interacted with chi-miR-15b-5p in DPCs. Based on both overexpression and silencing analysis of lncRNA-599547, our results indicate that lncRNA-599547 promotes the expression of Wnt10b in DPCs but without modulating its promoter methylation level. Using the mRNA-3'UTR fragments of goat Wnt10b containing the predicted binding sites of chi-miR-15b-5p in Dual-luciferase Reporter Assays, we show that lncRNA-599547 modulates the expression of Wnt10b at the chi-miR-15b-5p mediated post-transcriptional level. Taken together, our results indicate that lncRNA-599547 sponges miR-15b-5p to positively regulate the expression of Wnt10 gene, and thereby contributes the inductive property of DPCs in cashmere goat.

Thymosin β4 Identified by Transcriptomic Analysis from HF Anagen to Telogen Promotes Proliferation of SHF-DPCs in Albas Cashmere Goat

Increasing cashmere yield is one of the important goals of cashmere goat breeding. To achieve this goal, we screened the key genes that can improve cashmere performance. In this study, we used the RNA raw datasets of the skin and dermal papilla cells of secondary hair follicle (SHF-DPCs) samples of hair follicle (HF) anagen and telogen of Albas cashmere goats and identified a set of significant differentially expressed genes (DEGs). To explore potential associations between gene sets and SHF growth features and to identify candidate genes, we detected functional enrichment and constructed protein-protein interaction (PPI) networks. Through comprehensive analysis, we selected Thymosin β4 (Tβ4), Rho GTPase activating protein 6 (ARHGAP6), ADAM metallopeptidase with thrombospondin type 1 motif 15, (ADAMTS15), Chordin (CHRD), and SPARC (Osteonectin), cwcv and kazal-like domains proteoglycan 1 (SPOCK1) as candidate genes. Gene set enrichment analysis (GSEA) for these genes revealed Tβ4 and ARHGAP6 have a close association with the growth and development of SHF-DPCs. However, the expression of Tβ4 in the anagen was higher than that in the telogen, so we finally chose Tβ4 as the ultimate research object. Overexpressing Tβ4 promoted and silencing Tβ4 inhibited the proliferation of SHF-DPCs. These findings suggest that Tβ4 can promote the growth and development of SHF-DPCs and indicate that this molecule may be a valuable target for increasing cashmere production.