Molecular Characterization and Expression Pattern of Rheb Gene in Inner Mongolia Cashmere Goat (Capra hircus)

As one member of the Ras super family, Rheb is an upstream regulator of mTOR signaling pathway, which regulates the process of cell-growth, proliferation and differentiation. In order to study the relationship between Rheb and mTOR in Inner Mongolian Cashmere goat (Capra hircus) cells, Ras homolog enriched in brain (Rheb) gene cDNA was amplified by RT-PCR. It is 555 bp in length and includes the complete ORF encoding 184 amino acids (GenBank accession no. HM569224). The full cDNA nucleotide sequence has a 99% identity with that of sheep, 98% with cattle and 93% with human while their amino acids sequence shares identity with 98, 97 and 97% of them, correspondingly. The bio informatics analysis showed that Rheb has a Ras family domain, two casein kinase II phosphorylation sites, two ATP/GTP-binding sites motif A (P-loop), a prenyl group binding site (CAAX box). Tissue-specific expression analysis performed by semi-quantitative RT-PCR. The Rheb gene was expressed in all the tested tissues and the highest level of mRNA accumulation was detected in brain, suggesting that Rheb played an important role in goat cells.