Silencing MAP3K1 expression inhibits the proliferation of goat hair follicle stem cells

ChIP-Seq analysis reveals PRKACB as a target gene of HOXC13 involved in rabbit hair follicle development

Dermal papilla cells (DPCs) are key regulators of hair follicle (HF) development and growth, which not only regulate HF growth and cycling but play a role in the pathogenesis of hair loss. The transcription factor Homeobox C13 (HOXC13) can modulate the growth and development of HFs. Nevertheless, the specific genes and pathways regulated by HOXC13 in DPCs have yet to be determined. Thus, to gain a better understanding of genomic binding sites involved in HOXC13-regulated HF development, chromatin immunoprecipitation followed by high throughput sequencing (ChIP-Seq) was performed on rabbit DPCs with pcDNA3.1-3 × Flag-HOXC13 overexpression. A complete set of 9670 enrichment peaks was acquired by applying HOXC13-Flag ChIP. Subsequently, the peak sequence was annotated to the rabbit genome, revealing that 6.1 % of the peaks were identified within in the promoter region. Thereafter, five annotated genes were verified using RT-qPCR. The peak-associated genes were mainly enriched in signaling pathways related to HF development, such as MAPK and PI3K-Akt. Furthermore, by using a dual-luciferase reporter assay, we found that HOXC13 can target the protein kinase cAMP‑dependent catalytic β (PRKACB) promoter region (-1596 ∼ -1107 bp) and inhibit its transcription, which was consistent with data obtained from ChIP-seq analysis. Overexpression of PRKACB gene significantly modulated the expression of BCL2, WNT2, LEF1, and SFRP2 genes related to HF development as determined by RT-qPCR (P < 0.01, P < 0.05). The CCK-8 and flow cytometry assays showed that PRKACB significantly inhibited the proliferation of DPCs and promoted apoptosis (P < 0.01). In conclusion, our research revealed that PRKACB has the potential to serve as a novel target gene of HOXC13, contributing to the regulation of the proliferation and apoptosis of DPCs. The process of identifying global target genes can contribute to the understanding of the intricate pathways that HOXC13 regulates in the growth of HFs.

A homozygous missense mutation in the fibroblast growth factor 5 gene is associated with the long-hair trait in Angora rabbits

BACKGROUND

Rabbits are well-domesticated animals. As a crucial economic animal, rabbit has been successfully bred into wool-use, meat-use and fur-use breeds. Hair length is one of the most economically important traits affecting profitability in wool rabbits. In this study, to identify selection signatures with the long-hair trait, whole-genomic resequencing of long-haired rabbits (Angora rabbits) and short-haired rabbits (Rex and New Zealand rabbits) was performed.

RESULTS

By genome-wide selective sweeping analysis based on population comparison, we identified a total of 5.85 Mb regions (containing 174 candidate genes) with strong selection signals. Six of these genes (Dusp1, Ihh, Fam134a, Map3k1, Spata16, and Fgf5) were enriched in the MAPK signalling and Hedgehog signalling pathways, both of which are closely associated with hair growth regulation. Among these genes, Fgf5 encodes the FGF5 protein, which is a well-established regulator of hair growth. There was a nonsynonymous nucleotide substitution (T19234C) in the Fgf5 gene. At this locus, the C allele was present in all of the tested Angora rabbits, while the T allele was dominant in New Zealand and Rex rabbits. We further confirmed that the C allele was conserved in Angora rabbits by screening an additional 135 rabbits. Moreover, the results of functional predictions and co-immunoprecipitation revealed that the T19234C mutation impaired the binding capacity of FGF5 to its receptor FGFR1.

CONCLUSIONS

We discovered that the homozygous missense mutation T19234C within Fgf5 might contribute to the long-hair trait of Angora rabbits by reducing its receptor binding capacity. This finding will provide new insights into the genetic basis underlying the genetic improvement of Angora rabbits and benefit the improvement of rabbit breeding in the future.

Global Research Status and Trends in Hair Follicle Stem Cells: a Bibliometric Analysis

BACKGROUND

Hair follicle stem cells (HFSCs) are derived from the bulge region and are important autologous stem cell sources. Bibliometric is a statistical method that quantitatively analyses the research papers concerned about one special topic. This study aims to estimate the research status and trends of HFSCs worldwide by bibliometric analyses.

METHODS

Data were obtained from the Web of Science by searching keywords related to HFSCs. Publication distributions stratified by countries/regions, institutions, journals, and authors were systematically assessed. The frequency of keywords was assessed, and bibliometric mapping was employed to describe the development of HFSC research.

RESULTS

A total of 458 publications that met our screening criteria were included in this study, consisting of 423 (92.4%) articles and 35 (7.6%) reviews. The United States of America (USA) ranked first in the number of publications at 146 (31.9%), followed by China at 130 (28.4%), which is consistent with the rank of the H-index. Author keywords were classified into three clusters, namely, basic study, applied study, and biomarker; average publication time of keywords in applied study cluster is later than basic study cluster. The keywords "bulge", "nestin", and "skin" are the top three most frequent keywords in basic studies; "differentiation", "proliferation", and "alopecia" are the top three most frequent keywords in applied studies. With respect to the latest research hotspots, "apoptosis" and "tissue engineering" are relatively new keywords.

CONCLUSIONS

The USA and China were the most productive countries for research on HFSCs. The focus of keywords gradually shifted from basic study to applied study. Research on the differentiation/proliferation of HFSCs and the role of HFSCs in alopecia have been recent research focuses. Apoptosis and tissue engineering are recommended as promising research hotspots. Our study provides profound insights into the research history, current status, and future trend of HFSCs.

Effect of miR-101 on the Proliferation and Apoptosis of Goat Hair Follicle Stem Cells

The Yangtze River Delta white goat is a rare goat species capable of producing high-quality brush hair. Dual specificity protein phosphatase 1 (DUSP1) may play a role in the formation of high-quality brush hair, as evidenced by our previous research. We investigated the potential mechanisms that regulate the proliferation and apoptosis of goat hair follicle stem cells. We particularly focused on the relationship between DUSP1 and miR-101, which directly targets DUSP1, predicted and screened through bioinformatics websites. Then, fluorescence assays, flow cytometry, RT-qPCR, and Western blotting were used to investigate the effects of miR-101 on the proliferation and apoptosis of hair follicle stem cells. We found that miR-101 overexpression significantly decreased (p < 0.01) apoptosis and promoted the proliferation of hair follicle stem cells. Furthermore, the overexpression of miR-101 increased (p < 0.05) the mRNA and protein expression levels of the proliferation-related gene (PCNA) and anti-apoptotic gene (Bcl-2), and it decreased (p < 0.05) the mRNA and protein expression levels of the apoptotic gene (Bax). In conclusion, miR-101 can promote the proliferation of and inhibit the apoptosis of hair follicle stem cells by targeting DUSP1, which provides a theoretical basis for further elucidating the molecular mechanism that regulates the production of high-quality brush hair of Yangtze River Delta white goats.

DUSP6 inhibits the proliferation of hair follicle stem cells (HFSCs) in vitro

RNA-seq has shown that the DUSP6 and MAPK signaling pathways are associated with the production of high-quality brush hair (type III hair) in Yangtze River Delta white goats. However, there are few reports on the regulatory effects of DUSP6 expression on hair follicle stem cells (HFSCs) and cellular processes, as well as the underlying mechanism. Here, we investigated the effect of DUSP6 level in HFSCs and the molecular mechanism underlying the functional regulation of HFSCs by DUSP6. Overexpression of DUSP6 significantly suppressed the proliferation of HFSCs by inducing cell cycle arrest in the G1 phase and by promoting apoptosis. Transcriptome analysis revealed a total of 217 differentially expressed genes between DUSP6-overexpressing and control HFSCs, of which 33 (15.2%) were upregulated in DUSP6-overexpressing cells. The two pathways with the most significant enrichment of differentially expressed genes were the TNF signaling pathway and cytokine-cytokine receptor interaction pathway, and the significantly enriched terms in the GO enrichment analysis involved cell attachment and cytokines. These results indicate that DUSP6 can function as an inhibitory factor in HFSCs through the induction of cell cycle arrest in the G1 phase and can promote apoptosis by mediating crosstalk among several pathways and cytokines.HighlightsWe constructed DUSP6 overexpression vectors to detect mRNA and protein expression levels related to high-quality brush hair in MAPK signaling pathway.We found that high expression level of DUSP6 can inhibit the proliferation of hair follicle stem cells (HFSCs) and promote cell apoptosis of HFSCs.DUSP6 may be involved in the growth regulation of HFSCs like Other studies in cancer, tumors by regulating the expression of cytokines, changing the transmission of signals between cells, activating or suppressing immune-related pathways.