Cloning And Identification Of A Human Heart Developmental Candidate Gene Kbtbd7

BTB-kelch proteins play important roles in a variety of cellular functions including transcription regulation, cytoskeleton regulation, gating of ion channels, protein ubiquitination/degradation, angiogenesis and apoptosis. In this study, we have cloned anew member of BTB-kelch proteins,named KBTBD7, from a human embryonic heartcDNA library.The cDNA of KBTBD7 is 3008bp long, encoding a protein productof684 amino acids(77.2kD).The protein is highly conserved in evolution across different Species from Mus musculus, to Pan troglodytes,to Homo sapiens.Western blotanalysis indicate that a 77kD protein specific for KBTBD7 is expressed at defferent level of expression in heart ,liver,spleen,lung,kidney,skeletal muscle and intestineofembryo. In MCF-7 cells, KBTBD7 proteins are localizedtothecytoplasm. KBTBD7istranscriptionactivator when fused to GAL4 DNA-binding domain .Deletion analysis indicates that the BTB domain is a main region for transcriptional activation. Overexpression of KBTBD7in MCF-7 cells activates the transcription activities of activator protein-1(AP-1) and serum response element (SRE).These results suggest that KBTBD7 proteins may act as a new transcriptional activator in mitogen-activated protein kinase (MAPK) signaling pathway to mediate cellular functions.