NHE3 mobility in brush borders increases upon NHERF2-dependent stimulation by lyophosphatidic acid.

ABSTRACT: The epithelial brush border (BB) Na(+)/H(+) exchanger NHE3 is associated with the actin cytoskeleton by binding both directly and indirectly to ezrin; indirect binding is via attachment to NHERF family proteins. NHE3 mobility in polarized epithelial cell BBs is restricted by the actin cytoskeleton and NHERF binding such that only approximately 30% of NHE3 in the apical domain of an OK cell line stably expressing NHERF2 is mobile, as judged by FRAP analysis. Given that levels of NHE3 are partially regulated by changes in trafficking, we investigated whether the cytoskeleton association of NHE3 was dynamic and changed as part of acute regulation to allow NHE3 trafficking. The agonist studied was lysophosphatidic acid (LPA), an inflammatory mediator, which acutely stimulates NHE3 activity by

SUBMITTER: Cha B 

PROVIDER: S-EPMC2936692 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature