Disruption of the eNOS zinc-tetrathiolate cluster results in the movement of a newly identified 'flexible arm' region that blocks substrate access to the catalytic site, preventing eNOS uncoupling.
Rather than being a constitutive enzyme as was first suggested, endothelial nitric oxide synthase (eNOS) is dynamically regulated at the transcriptional, posttranscriptional, and posttranslational levels. This review will focus on how changes in eNOS function are conferred by various posttranslational modifications. The latest knowledge regarding eNOS targeting to the plasma membrane will be discussed as the role of protein phosphorylation as a modulator of catalytic activity. Furthermore, new data are presented that provide novel insights into how disruption of the eNOS dimer prevents eNOS uncoupling and the production of superoxide under conditions of elevated oxidative stress and identifies a novel regulatory region we have termed the 'flexible arm'.
Rafikov et al. (Fri,) reported a review. Disruption of the eNOS zinc-tetrathiolate cluster results in the movement of a newly identified 'flexible arm' region that blocks substrate access to the catalytic site, preventing eNOS uncoupling.