Cardiac Tyrosine 97 Phosphorylation of Cytochrome <i>c</i> Regulates Respiration and Apoptosis.

ABSTRACT: It was previously reported that tyrosine 97 (Y97) of cytochrome c is phosphorylated in cow heart tissue under physiological conditions. Y97 phosphorylation was shown to partially inhibit respiration in vitro in the reaction with purified cytochrome c oxidase. Here, we use phosphomimetic Y97E Cytc to further characterize the functional effects of this modification both in vitro and in cell culture models. In vitro, phosphomimetic Y97E Cytc showed lower activity in the reaction with purified cow heart cytochrome c oxidase (COX), decreased caspase-3 activity, and reduced rate of reduction. Additionally, the phosphomimetic Y97E Cytc tended to be resistant to heme degradation and showed an increased rate of oxidation. Intact mouse Cytc double kno

SUBMITTER: Morse PT 

PROVIDER: S-EPMC11818311 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature