The transient receptor potential channel TRPC6 is a non-selective cation channel which modulates the calcium level in eukaryotic cells (including sensory receptor cells) in response to external signals. Calmodulin (CaM) is a ubiquitously expressed Ca(2+) binding protein that is an important mediator of Ca(2+)-dependent regulation of the TRPC6 channel. One CaM binding site was identified within the C-tail of TRPC6. The aim of this study is to map in detail the CaM and inositol (1,4,5)-triphosphate receptor binding (CIRB) domain in the C-terminal region of mouse TRPC6 that is capable of interacting with CaM using in vitro binding assays. Besides the set of positively charged amino acid residues Arg852, Lys856, Arg864, Lys859/Arg860, a hydrophobic Ile857, at the position 1 in 1-5-10 motif, was located and the effect of replacing it with a neutral residue was tested using fluorescence anisotropy measurement. Participation of Ile857 could indicate a strong role of this conserved CaM binding motif.

Institute of Physiology Academy of Sciences of the Czech Republic Prague Czech Republic

Citace poskytuje Crossref.org

Characterization of the S100A1 protein binding site on TRPC6 C-terminus

Integrative binding sites within intracellular termini of TRPV1 receptor

PtdIns(4,5)P2 interacts with CaM binding domains on TRPM3 N-terminus

Calmodulin and S100A1 protein interact with N terminus of TRPM3 channel