Glycosylation of asparagines 136 and 184 is necessary for the α2δ subunit-mediated regulation of voltage-gated Ca2+ channels

摘要: Abstract The CaVα2δ auxiliary subunit is a glycosylated protein that regulates the trafficking and function of voltage-gated Ca2+ channels. One most prominent roles to increase whole-cell current amplitude. Using N-glycosidase F truncated forms CaVα2δ, earlier studies suggested an important role for N-linked glycosylation in stimulation. Here, we used site-directed mutagenesis heterologous expression HEK-293 cells examine impact individual sites within on regulation Ba2+ currents through recombinant We found two N-glycosylation consensus (NX(S/T)) extracellular α2 domain are functional. Substitution asparagines glutamines at amino acid positions 136 184 rendered these non-functional as shown by patch-clamp experiments. These results corroborate required subunit-induced stimulation suggest N136 N184 directly involved this action. Likewise, N136Q N184Q mutations prevented without altering its kinetic properties, suggesting number functional channels plasma membrane.