The Circular RNA CircCOL1A1 Functions as a miR-149-5p Sponge to Regulate the Formation of Superior-Quality Brush Hair via the CMTM3/AR Axis

Integrative and comparative analysis of whole-transcriptome sequencing in circCOL1A1-knockdown and circCOL1A1-overexpressing goat hair follicle stem cells

OBJECTIVE

Hair morphogenesis is tightly related to hair follicle stem cells (HFSCs) proliferation and hair follicle (HF) development. Yangtze River Delta white goats (YRDWG) HFSCs are important for producing superior-quality brush hair (SQBH). Nonetheless, the known regulatory mechanisms are not sufficient to explain YRDWG gHFSCs growth, HF development, and SQBH formation.

METHODS

To deeply investigate the interaction networks and mechanisms of circCOL1A1 in the HF development and SQBH formation of YRDWG in detail, we applied whole-transcriptome sequencing and bioinformatics analysis of circCOL1A1-knockdown and circCOL1A1-overexpressing HFSCs from YRDWG. STRING and other databases were used to construct multiple interaction networks. Differentially expressed (DE) genes, DE-miRNAs, and DE-circRNAs were further confirmed via real-time quantitative polymerase chain reaction and Sanger sequencing.

RESULTS

A total of 87 genes, 96 miRNAs, and 135 circRNAs were DE between circCOL1A1-knockdown and circCOL1A1-overexpressing gHFSCs. Functional enrichment, gene ontology annotation and Kyoto encyclopedia of genes and genomes analyses identified marked enrichment of these DE- genes, DE-miRNAs, and DE-circRNAs in the MAPK, PI3K/Akt, and focal adhesion signaling pathways, which are closely associated with gHFSCs growth and HF development. In addition, through interaction network construction, four important regulatory axes were obtained, namely, the chi-circCOL1A1-miR-149-5p-CMTM3-AR, chi-circACTN1- miR-671-5p-MAPK3/COL13A1, chi-circITGA6-miR-18a-5p-FGF1/MAP3K1 and chi-circ COBLL1-miR-30a-5p/miR-128-3p-ITGA6/MAPK14/FGF14 axes.

CONCLUSION

These novel findings provide a valuable and comprehensive basis for investigating the complex mechanism by which circRNAs participate in and regulate HF development and SQBH formation in YRDWG.

miR-133a-3p and miR-145-5p co-promote goat hair follicle stem cell differentiation by regulating NANOG and SOX9 expression

OBJECTIVE

Hair follicle stem cells (HFSCs) differentiation is a critical physiological progress in skin hair follicle (HF) formation. Goat HFSCs differentiation is one of the essential processes of superior-quality brush hair (SQBH) synthesis. However, knowledge regarding the functions and roles of miR-133a-3p and miR-145-5p in differentiated goat HFSCs is limited.

METHODS

To examine the significance of chi-miR-133a-3p and chi-miR-145-5p in differentiated HFSCs, overexpression and knockdown experiments of miR-133a-3p and miR-145-5p (Mimics and Inhibitors) separately or combined were performed. NANOG, SOX9, and stem cell differentiated markers (β-catenin, C-myc, Keratin 6 [KRT6]) expression levels were detected and analyzed by using real-time quantitative polymerase chain reaction, western blotting, and immunofluorescence assays in differentiated goat HFSCs.

RESULTS

miR-133a-3p and miR-145-5p inhibit NANOG (a gene recognized in keeping and maintaining the totipotency of embryonic stem cells) expression and promote SOX9 (an important stem cell transcription factor) expression in differentiated stem cells. Functional studies showed that miR-133a-3p and miR-145-5p individually or together overexpression can facilitate goat HFSCs differentiation, whereas suppressing miR-133a-3p and miR-145-5p or both inhibiting can inhibit goat HFSCs differentiation.

CONCLUSION

These findings could more completely explain the modulatory function of miR-133a-3p and miR-145-5p in goat HFSCs growth, which also provide more understandings for further investigating goat hair follicle development.

Regulation of Proliferation and Apoptosis of Hair Follicle Stem Cells by miR-145-5p in Yangtze River Delta White Goats

Yangtze River Delta white goats are the sole goat breed producing brush hair of high quality. The gene DUSP6 has been extensively studied in tumor cells but rarely in hair follicle stem cells (HFSCs). Per the previous sequencing data, it was determined that DUSP6 expression was up-regulated in superior-quality brush hair tissues, confirming it as a candidate gene associated with this trait. The targeting relationship of miR-145-5p with DUSP6 was determined based on online database prediction and was authenticated using a dual-luciferase gene reporter assay and quantitative reverse-transcription PCR (RT-qPCR). The regulatory effect of miR-145-5p on the growth of HFSCs was determined by targeting DUSP6 with RT-qPCR, 5-ethynyl-2'-deoxyuridine assays, Western blotting, and flow cytometry. The proliferation of HFSCs was inhibited and their apoptosis capacity was enhanced due to the presence of miR-145-5p. Therefore, it was proposed that this may have occurred through a repression effect of DUSP6 on the MAPK signaling pathway. The regulatory network of the HFSCs can be further understood using the theoretical basis established by the findings derived from this study.

Circ-TRIO promotes TNBC progression by regulating the miR-432-5p/CCDC58 axis

Numerous studies have shown that circRNAs are aberrantly expressed in various cancers and play a significant role in tumor progression. However, the molecular mechanisms of circRNAs in triple-negative breast cancer (TNBC) remain ambiguous. By intersecting throughput data and qRT-PCR results from tissues and cell lines, circ-TRIO was identified as a potential oncogenic regulator of TNBC. Moreover, circ-TRIO expression was detected in TNBC tissues and was correlated with the recurrence and prognosis of TNBC patients. The circular characteristics of circ-TRIO were verified by RNase R and CHX assays. Functionally, the knockdown of circ-TRIO inhibited the proliferation, migration and invasion of TNBC cells, while the overexpression of circ-TRIO resulted in the opposite impacts. Mechanistically, a dual luciferase reporter assay and RNA immunoprecipitation were performed and indicated that circ-TRIO could combine with miR-432-5p to regulate the expression of coiled-coil domain containing 58 (CCDC58). In summary, our study illustrates that circ-TRIO plays an important role in the progression of TNBC by regulating the miR-432-5p/CCDC58 axis, which could broaden our insight into the underlying mechanisms and provide a novel prognostic marker of TNBC in the clinic.