Cloning and expression of cold-inducible RNA binding protein in domestic yak (Bos grunniens)

Cold-inducible RNA binding protein (CIRP) is over-expressed during cold and many other stresses, and could regulate the adaptation to hypothermia. In the present investigation, the objective was to determine the expression of CIRP in adult yak heart, liver, spleen, lung, kidney, brain, ovary, testis and skin by relative quantitative real time polymerase chain reaction (RT-PCR), Western blot and immunohistochemistry from mRNA and protein levels. The CIRP open reading frame encoding was cloned from the domestic yak brain. Results of RT-PCR and Western blot showed the high expression level of CIRP in the heart, kidney, brain, testis and skin, and the lower expression level of CIRP in the lung. Immunohistochemical staining showed CIRP was expressed in the nucleus of neuronal cells, spermatogonia, primary spermatocytes and epidermal cells, and in the cytoplasm of the residual tissues. These observations may provide new data to understand and further study the important role of CIRP protein in the plateau adaptation of the domestic yak on long-term evolution.