A Novel Auxiliary Subunit Critical to BK Channel Function in Caenorhabditis elegans

作者：Chen Bojun; Ge Qian; Xia Xiao Ming; Liu Ping; Wang Sijie J; Zhan Haiying; Eipper Betty A; Wang Zhao Wen^*

来源：Journal of Neuroscience, 2010, 30(49): 16651-16661.

DOI：10.1523/JNEUROSCI.3211-10.2010

The BK channel is a Ca(2+)- and voltage-gated potassium channel with many important physiological functions. To identify proteins important to its function in vivo, we screened for Caenorhabditis elegans mutants that suppressed a lethargic phenotype caused by expressing a gain-of-gf) isoform of the BK channel alpha-subunit SLO-1. BKIP-1 (for BK channel interacting protein), a small peptide with no significant homology to any previously characterized molecules, was thus identified. BKIP-1 and SLO-1 showed similar expression and subcellular localization patterns and appeared to interact physically through discrete domains. bkip-1 loss-of-lf) mutants phenocopied slo-1(lf) mutants in behavior and synaptic transmission and suppressed the lethargy, egg-laying defect, and deficient neurotransmitter release caused by SLO-1(gf). In heterologous expression systems, BKIP-1 decreased the activation rate and shifted the conductance-voltage relationship of SLO-1 in a Ca(2+)-dependent manner and increased SLO-1 surface expression. Thus, BKIP-1 is a novel auxiliary subunit critical to SLO-1 function in vivo.

• 出版日期2010-12-8