Cloning, molecular characterization, and expression pattern of FGF5 in Cashmere goat (Capra hircus)

Fibroblast growth factor 5 (FGF5) is a secreted signaling protein that belongs to the FGF family, and was found to be associated with hair growth in humans and other animals. The Inner Mongolia Cashmere goat (Capra hircus) is a goat breed that provides superior cashmere; this breed was formed by spontaneous mutation in China. Here, we report the cloning, molecular characterization, and expression pattern of the Cashmere goat FGF5. The cloned FGF5 cDNA was 813 base pairs (KM596772), including an open reading frame encoding a 270-amino-acid polypeptide. The nucleotide sequence shared 99% homology with Ovis aries FGF5 (NM_001246263.1). Bioinformatic analysis revealed that FGF5 contained a signal peptide, an FGF domain, and a heparin-binding growth factor/FGF family signature. There was 1 cAMP- and cGMP-dependent protein kinase phosphorylation site, 11 protein kinase C phosphorylation sites, 4 casein kinase II phosphorylation sites, 1 amidation site, 1 N-glycosylation site, and 1 tyrosine kinase phosphorylation site in FGF5. Real-time polymerase chain reaction showed that FGF5 mRNA levels were higher in testis than in the pancreas and liver. These data suggest that FGF5 may play a crucial role in Cashmere goat hair growth.