Transcriptomic analysis reveals critical genes for the hair follicle of Inner Mongolia cashmere goat from catagen to telogen

Abstract

There are two main types of hair follicle in Inner Mongolia Cashmere goats, the primary hair follicle (PHF) producing hair fibers and the secondary hair follicle (SHF) producing cashmere fibers. Of both fibers from cashmere-bearing goats in Aerbasi, Inner Mongolia, the timing of cyclical phases for the cashmere have been well clarified but hair fibers have been less noticeable. Herein, we evaluated transcriptome of PHF and SHF from the same three goats in Aerbasi at the catagen- and telogen phase of cashmere growth. We totally found 1977 DEGs between PHFs at the telogen and catagen phases of SHF, 1199 DEGs between telogen- and catagen SHF, 2629 DEGs between PHF at the catagen phase of SHF and catagen SHF, and 755 DEGs between PHF at the telogen phase of SHF and telogen SHF. By analyzing gene functions based on GO and KEGG database, we found that the DEGs have functions in muscle contraction and muscle filament sliding between catagen- and telogen SHF, indicating that arrector pilli muscles might play a role on the transition from catagen to telogen. Moreover, considering that the enriched GO and KEGG categories of the DEGs between PHF and SHF, we suggested that part of PHF might rest in their own anagen phase when SHF are at catagen, but PHF might enter into the telogen phase at SHF's telogen. Finally, we highly recommended the several potential genes acting as the regulators of the transition between growth phases including IL17RB and eight members of ZNF. These results provide insight into molecular mechanisms on the transition of SHF from catagen to telogen together with PHF's growth situation at SHF's catagen and telogen in Inner Mongolia Cashmere goats.

Fig 1

(a) is Inner Mongolia Autonomous Region map and the location is Otog Banner where Inner Mongolia Cashmere goat strain line of Aerbasi mainly distributed. (b) is a female goat of this breed.

Fig 2. Gene structure in catagen and telogen of SHF and PHF.

The number of exons of SHF in catagen and telogen respectively are 20617193 and 19999609, introns are 4822842 and 2832110, intergenic regions are 1309521 and 6618361. However, the number of exons of PHF in catagen and telogen respectively are 27541761 and 19455711, introns are 5950502 and 3337148, intergenic regions are 1387033 and 5853974. From the figure, we can find that in these four samples, the largest number is exon. But for intron and intergenic regions, there are some differences between catagen and telogen. In catagen, the number of intron is higher than intergenic regions, while in telogen is opposite.

Fig 3. IL17RB, HPS6 and ALPL was detected by the qRT-PCR, and the trend was similar to RNA-seq.

** p-value < 0.01, * p-value < 0.05.

Fig 4. IL17RB-IL17E pathway may due to epithelial cells apoptosis.