Molecular characterization of the porcine STAT4 and STAT6 genes.

Signal transducers and activators of transcription (STATs) are members of a recently identified family of transcription factors that activate gene transcription in response to a number of different cytokines. STAT4 and STAT6 were activated by interleukin (IL)-12 and IL-4 stimulation, which were important for the generation of Th1 and Th2 cells. In this study, we cloned the cDNA sequences and analyzed the genomic structure of porcine STAT4 (poSTAT4) and STAT6 (poSTAT6) genes. Chromosome localization assigned these two genes to SSC15 and SSC5, and they were most closely linked to maker SWR1002 and DK. The RT-PCR revealed that both genes were expressed in eight diverse tissues, with the highest level in small intestine, followed by lung, kidney, muscle and stomach, whereas expressions in heart, liver and spleen were relatively weak. Transient transfection indicated that poSTAT4 and poSTAT6 proteins distributed throughout the whole porcine hip artery endothelial cell. A single nucleotide polymorphism (A/G), which can be recognized by restriction enzyme TaiI, was identified at the 3' untranslated region of poSTAT6, and genotyping results showed apparent variation in allele frequency between Chinese indigenous and western breeds.