Stable expression of MCHR2 in CHO cell line and analysis of its signal transduction pathways / 中国药理学通报

ABSTRACT

Aim To construct a eukaryotic expression vector of human MCHR2 and to analyze the stable expression and signal transduction pathways of MCHR2 in CHO cells. Methods The full-length MCHR2 cDNA fragment was amplified by PCR from the human fetal brain cDNA library and inserted into eukaryotic expres-sion vector pcDNA3.1(+), resulted in the recombinant expression vector pcDNA3.1-MCHR2. The recombinant plasmid was confirmed by the restriction enzymatic digestion and DNA sequencing analysis, and then transfected into CHO cells by lipofectamine. A stably-transfected cell line was obtained by the dominant G418 selection, and the expression of the MCHR2 gene on transcription and translation levels were identified by RT-PCR and Western blot. Signal transduction pathways mediated by MCHR2 were analyzed by measurement of intracellular cAMP and calcium. Results The eukaryotic expression vector pcDNA3.1-MCHR2 was successfully constructed and the MCHR2 gene was stably transfected into CHO cells. A stably-transfected cell line was established and the MCHR2 gene was efficiently transcribed and translated. MCH stimulation had no effect on the production of cAMP, however, it could induce a clear and transient increase of intracellular calcium, suggesting that MCHR2 was only coupled to Gq protein. Conclusion The stable expression of MCHR2 and analysis of its signal transduction pathways in CHO cell line provided a solid experimental foundation for further studies on the function of the MCHR2 gene in vitro.