Abstract：Paired-liked homodomain transcription factor 2 (PITX2) is an important transcription factor of Wnt/β-catenin signaling pathway, and plays an important role in cell proliferation, differentiation, organogenesis, pituitary development and embryonic development. Different tissues of Saanen dairy goats (Capra hircus) were collected as the experimental materials in this study. The PITX2 gene was cloned and analyzed using reverse transcription-polymerase chain reaction (RT-PCR), TA cloning and bioinformatic methods, meanwhile the mRNA expression profiles of this gene was revealed using quantitative Real-time PCR (qRT-PCR). The results showed that the coding sequence of PITX2 gene was 978 bp, encoding 325 amino acids, which shared 99%, 95%, 90%, 90% and 93% homology with Bos taurus, Sus scrofa, Mus musculus, Rattus norvegicus and Homo sapiens, respectively. The PITX2 gene expressed in varied tissues of rams and ewes, which showed a broad spectrum of gene expression. The expression of PITX2 gene was the highest in pancreas of ram, followed by small intestine, lungs and muscles, and the lowest in spleen. Moreover, the expression levels in pancreas, lungs, small intestine and muscles were significantly higher than that in other tissues. The expression of PITX2 gene was the highest in liver of ewe, followed closely by breast, lungs, and the lowest in adipose tissue. Moreover, the expression of breast was significantly higher than that in heart, kidney, muscle and adipose tissues, which suggested that this gene might be related with lactation performance. The results will lay a foundation for further study of the gene function in the regulation of lactation.
