Molecular Cloning And Expression Analysis Of KCNQ1Gene In The Golden Hamster

KCNQ1gene is a member of Kcnq family, and also a member ofvoltage-dependent potassium channel family, which was first identified in a linkagestudy looking at some of the genetic causes of sudden death from cardiac arrhythmia.Hamster is not only a medium-sized pet, but also a very good experimental animaland widely used in various fields. To lay a basic foundation in human physiology,genetics, pharmacology and pathology, KCNQ1gene cDNA sequence was cloned andanalyzed based on golden hamster in this research. Subsequently, its expression wasanalyzed in several hamster tissues.Hamster heart cDNA was used as the template. RT-PCR and RACE techniquewere employed to clone KCNQ1gene cDNA sequence, which encoding669aa with atotal length of3050base pair. Comparing with other species in the Genbank, goldenhamster KCNQ1gene cDNA sequence and the amino acid sequence were highconservative. the homologies of KCNQ1cDNA were92%(the hightest),90%and87%respectively, compared with rat, mouse and human. The homologies of theamino acids were97%,97%and90%respectively compared with rat, murine andhuman.According to the predicted amino acid sequence, its protein molecular weightmay be74.68KDa, and the isoelectric point was9.77. KCNQ1protein may have sixtransverse expansion (S1-S6), the positions were123-146,155-178,198-218,263-283,294-317, and331-354. Predicted by software, glycosylation might occur in the sixlocus of KCNQ1protein. Then the phylogenetic tree of the golden hamster KCNQ1gene was constructed, which showed the genetic relationship of golden hamster isconsistent with traditional taxonomy results.Subsequently, total RNAs were extracted from heart, liver, spleen, lung andkidney. KCNQ1cDNA fragments were amplified using RT-PCR. Expressiondifferences in a variety of organs were detected by semi-quantitative RT-PCR.Realtime PCR results showed that KCNQ1gene was highly expressed in heart, lung and kidney, slightly expressed in spleen, while almost no expression in liver. Itsexpression in heart was the highest.