Molecular cloning and tissue distribution of the phosphotyrosine interaction domain containing 1 (PID1) gene in Tianfu goat.

Phosphotyrosine interaction domain containing 1 (PID1) is an important mediator in the development of obesity-related insulin resistance in humans and animals. For a better understanding of the structure and function of the PID1 gene and to study its effect in caprine, the cDNA of the PID1 gene from the abdominal muscle of Tianfu goat was cloned and sequenced. The structure of PID1 was analyzed using bioinformatics tools. The results showed that the full sequence of the caprine PID1 cDNA was 896 bp long and contained a 654 bp long coding region that encoded a 217 amino acid sequence. Fifteen phosphorylation sites were predicted in the translated PID1 protein. The protein had a phosphotyrosine-binding domain between Arg(53) and Ile(199). A phylogenic tree based on the PID1 proteins from other species revealed that the caprine protein was closely related to cattle PID1. Fluorescence quantitative PCR analyses revealed that PID1 was expressed in the heart, liver, spleen, lung, kidney, leg muscle, abdominal muscle and longissimus dorsi muscle of goats. In particular, high expression levels of PID1 were detected in liver and abdominal muscle, and low expression levels were seen in lung. Furthermore, the PID1 mRNA expression levels in the longissimus dorsi muscles increased gradually with the age of the goats (P<0.05). Western blotting results detected the PID1 protein in six of the tissues in which PID1 was shown to be expressed; the two exceptions were liver and spleen.