PKC phosphorylation of titin's PEVK element: a novel and conserved pathway for modulating myocardial stiffness.

ABSTRACT:

Rationale

Protein kinase C (PKC) regulates contractility of cardiac muscle cells by phosphorylating thin- and thick- filament-based proteins. Myocardial sarcomeres also contain a third myofilament, titin, and it is unknown whether titin can be phosphorylated by PKC and whether it affects passive tension.

Objective

The purpose of this study was to examine the effect of PKC on titin phosphorylation and titin-based passive tension.

Methods and results

Phosphorylation assays with PKCalpha revealed that titin is phosphorylated in skinned myocardial tissues; this effect is exacerbated by pretreating with protein phosphatase 1. In vitro phosphorylation of recombinant protein representing titin's spring elements showed that PKCalpha targets the proline - glutamate - valine -

SUBMITTER: Hidalgo C 

PROVIDER: S-EPMC2764991 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature