Identification of genes preferentially expressed in goat hair follicle anagen-catagen transition using suppression subtractive hybridization.

Suppressive subtraction hybridization (SSH) was used to identify differentially expressed genes in goat (Capra hircus) hair follicle anagen-catagen transition. The cDNA fragments, derived from SSH positive subtractive library (tester: anagen-catagen transition, driver: later anagen), were cloned into pEGM-T vector. Two hundred cDNA fragments screened from this library were subjected to identify forty-five unregulated isolates. Sequence analysis revealed that these fragments represented twenty-three genes. Blasting analysis with database in GenBank showed that twenty genes were previously clearly annotated, two were homologous to un-annotated expressed sequence tag (ESTs), and one might be novel. To identify characters of gene expression, seven genes in later anagen and anagen-catagen transition skin tissues were chosen for quantitative real-time PCR. Results indicated that expression of these seven genes varied much, reaching threefold among them, furthering indicating that expression of those genes was up-regulation in the anagen-catagen transition. We characterized expression levels of this potential novel gene and the goat ectodysplasin A during differential stages of hair cycle. These profiles suggested that these two genes might play a role in the goat secondary hair follicle cycle.