Cloning, Chromosome Mapping, Characterization Of Porcine RGS2 And Gαq/11

Adipocyte is originated from Mesenchymal stem cell which resides in mesoblast. It is mainly distributed in fat tissue and bone marrow which can differentiate into adipocyte, osteoblasts and cartilage.Whereas the middle and late stages of adipogenesis have been well studied, little is known about the earliest step of adipocyte differentiation and related reporte is infrequent.Regulator of G protein signaling (RGS) protein 2 (RGS2) is an important signal molecular involved in signal transduction of hormones, neurotransmitters and sensory stimuli in animal body. As a G protein molecular switch, it play important roles to coordinate the wide range of responses elicited by extracellular stimuli.A report issued recently indicated that RGS2 is an important factor during earliest step of adipocyte differentiation;From an observation about preadipocyte cells differentiation of mouse subcutaneous tissue,only Gaq/11 is expressed decreasly markedly in all G protein a subunits,and this indicated that Gaq/11 is related closly with preadipocyte cells differentiation. After all, RGS2 acts with Gaq directly.So the cooperation between two proteins maybe be invovled into regulation during the earliest step of adipocyte differentiation.In the present study, based on the knowned human RGS2, Gaq/11 nucleotide sequence, their counterparts in pig were cloned by in silico cloning and homologe sequence method. According to the acquired cDNA sequence in pig and the RGS2 gene tables in huaman and rat, primers were designed and introns were cloned. At last RGS2 genomic sequence were cloned. It was found that the coding domains of these three genes have high identity (94-100%) between human and pig. Especially, amino acid sequence of Gaq is conserved completely in Homo sapiens, Macaca mulatta, Mus musculus, Rattus norvegicus, Monodelphis domestica and Sus scrofa. RGS2 gene has the same gene table with human and mouse, and all of the junctions between the introns and exons conform perfectly to the GT/AG rule.The three genes were mapped finely by radiation hybrid mapping, which were located to 10p, 1q21-2 and 2q21-24 respectively. Our results are consistent with the porcine-human comparative map.The tissue distribution profiles of the three genes were acquired by semi-quantity RT-PCR. The tissues examined include liver, heart, muscle, kidney, spleen, lung, stomach, adipose tissue, brain, uterus, gut. The three genes are expressed ubiquitously. RGS2 was shown to be expressed in muscle, liver, heart, spleen, lung, fat tissue, brain, uterus. But it...