Determination of Secondary Follicle Characteristics, Density, Activity, and Hoxc13 Expression Pattern of Hexi Cashmere Goats Breed

Abstract

This experiment was conducted to identify some aspects of secondary follicle (SF) characteristics of Hexi cashmere goats at five different growing stages in one year in order and discover the expression pattern of Hoxc13 in a SF cycling to provide morphological basis for studying the growth of cashmere. Ten cashmere goats of one-year old (5 males, 5 females) were included in this study. The density and activity of SF were observed and measured by making paraffin sections, the ultra-structural features of SF were studied under transmission electron microscopy (TEM) by making ultra-thin sections, and the expression of Hoxc13 was investigated through the immunohistochemistry method. The average diameter of SF had the smallest value in the anagen stage, and significant difference (P < 0.05) was found between the anagen stage and other stages. The density of SF increased gradually through the different growing stages, and significant difference was found between the anagen and procatagen stages (P < 0.05). With an increase in time (months), the percentage of SF activity increased, and significant difference in the percentage of SF activity was found between the telogen and anagen stages (P < 0.05). At the telogen stage, the layers of connective tissue sheath (CTS) of SF were unclear, hemidesmosomes between the outer root sheath (ORS) and basement membrane disappeared, and dead cells were found at the top of the SF. The rudiments of new SF were found in the proanagen stage, CTS was thickened, and the cells of ORS were stretched out like fingers. At the anagen stage, the structure of SF was integral, and the inner root sheath (IRS) consisted of three concentric layers (Helen, Huxley, and Cuticle layers). The cells of Huxley's layer degenerated gradually, and pseudopodia were formed on the cells of ORS in the procatagen stage. At the catagen stage, the ORS was separated from the IRS, and IRS disappeared. Huxley's layer was absent in the inactive SF while, the ORS was present in the active SF. Hoxc 13 was expressed in the epidermis and sebaceous gland o, ORS, IRS, hair shaft of SF in the skin. Hoxc13 was expressed weakly during procatagen, catagen, and telogen stage, while with an increase in proanagen and ana-

HOXC13 and HSP27 Expression in Skin and the Periodic Growth of Secondary Fiber Follicles from Longdong Cashmere Goats Raised in Different Production Systems

“…Data in Tables and revealed that the diameter, depth, density and activity of SF in both group of Longdong cashmere goat had a growing tendency in anagen stage. It was consistent with the study on Inner Mongolia Cashmere goat (Li et al, ) and Hexi cashmere goat (He et al, ). The difference was that the largest value of diameter, depth and activity of SF in extensively fed group presented in September, while the value of diameter, depth density and activity of SF presented in October.…”

“…Wu et al () found that the activity of hair follicle was highly correlated with the expression of Hoxc13 gene. The research of SF in Hexi cashmere goat have also found that the activity changes of SF and the expression of Hoxc13 are closely related (He et al, ). HSP can be detected in all organisms (Kakobsson et al, ; Zhang et al, 2014; Gautam et al, ; Murphy 2013).…”

“…The expression of HOXC13 in the ORS of the SF was strong, indicating that the protein plays a very important role in maintaining the function of the ORS. Our previous studies (He et al, 2015) have shown that newborn secondary follicles can be generated beside the ORS, suggesting that HOXC13 may play an important role in the generation of new hair follicles. The strong expression of HSP27 and HOXC13 during anagen and weak reactivity in the catagen and telogen, suggests the two proteins involved in the cycle of secondary follicle growth changes, and plays an important role.…”

“…HOXC13 belongs to the Abd‐B class of Hox gene family members and is involved in goat hair follicle formation and hair growth (Wu et al, ). Research has revealed that HOXC13 expression correlates with cashmere goat skin thickness (Wu et al, ) and He et al () found that HOXC13 was expressed in the skin epidermis and the outer root sheath (ORS) of SF. They revealed a correlation between the expression of HOXC13 and the activity of the SF.…”

Genome-Wide Characterization of Selection Signatures and Runs of Homozygosity in Ugandan Goat Breeds

“…The homeobox genes HOXC12 and HOXC13 genes identified in Sebei are involved in the anterior/posterior pattern specification (GO:0009952). The genes play a role in hair follicle differentiation, growth, and development by regulating the keratin differentiation-specific genes ( Wu et al, 2009 ; Taye et al, 2017 ). The HOXC13 gene has been reported to influence skin thickness.…”