Long noncoding RNA and gene expression analysis of melatonin-exposed Liaoning cashmere goat fibroblasts indicating cashmere growth.

Cashmere produced from Liaoning cashmere goat is highly valuable. Melatonin is an important factor affecting cashmere growth and can regulate the growth cycle via effects on gene expression. Long noncoding RNAs (lncRNAs) regulate gene expression, but detailed studies of their effect on hair growth are lacking. To explore how lncRNA mediates the effects of melatonin on cashmere growth, we used RNA-Seq including a control condition (C) and three melatonin treatments (1.0 g/L 24 h (M1_24H), 0.2 g/L 24 h (M2_24H), 0.2 g/L 72 h (M2_72H)). M1_24H, M2_24H, and M2_72H had 32, 10, and 113 differentially expressed lncRNAs, respectively. Gene ontology (GO) and pathway analyses results showed that melatonin was most beneficial to cashmere growth at 0.2 g/L 72 h, and nuclear factor (NF)-κB signaling corresponding to an effect of LncRNA MTC was involved in hair follicle development. We found that melatonin upregulated XLOC_005914 lncRNA (LncRNA MTC). Proliferation increased in the 0.2 g/L 72 h condition and cells with high LncRNA MTC expression, but it was reduced in fibroblasts with knocked down LncRNA MTC expression. This is the first report that LncRNA MTC promotes fibroblast proliferation and regulates hair follicle development and cashmere growth by activating NF-κB signaling.