Referenced in: none

Automatically associated channels: Kv1.5

Title: alpha-actinin-2 couples to cardiac Kv1.5 channels, regulating current density and channel localization in HEK cells.

Authors: N D Maruoka, D F Steele, B P Au, P Dan, X Zhang, E D Moore, D Fedida

Journal, date & volume: FEBS Lett., 2000 May 12 , 473, 188-94

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/10812072

Abstract
Voltage-gated K(+) (Kv) channels are particularly important in the physiology of excitable cells in the heart and the brain. PSD-95 is known to cluster Shaker channels and NMDA receptors and the latter is known to couple through alpha-actinin-2 to the post-synaptic cytoskeleton [Wyszynski et al. (1997) Nature 385, 439-442], but the mechanisms by which Kv channels are linked to the actin cytoskeleton and clustered at specific sites in the heart are unknown. Here we provide evidence that Kv1.5 channels, widely expressed in the cardiovascular system, bind with alpha-actinin-2. Human Kv1.5 interacts via its N-terminus/core region and can be immunoprecipitated with alpha-actinin-2 both after in vitro translation and from HEK cells expressing both proteins. The ion channels and alpha-actinin-2 co-localize at the membrane in HEK cells, where disruption of the actin cytoskeleton and antisense constructs to alpha-actinin-2 modulate the ion and gating current density.