Four-and-a-half LIM domains proteins are novel regulators of the protein kinase D pathway in cardiac myocytes.

ABSTRACT: PKD (protein kinase D) is a serine/threonine kinase implicated in multiple cardiac roles, including the phosphorylation of the class II HDAC5 (histone deacetylase isoform 5) and thereby de-repression of MEF2 (myocyte enhancer factor 2) transcription factor activity. In the present study we identify FHL1 (four-and-a-half LIM domains protein 1) and FHL2 as novel binding partners for PKD in cardiac myocytes. This was confirmed by pull-down assays using recombinant GST-fused proteins and heterologously or endogenously expressed PKD in adult rat ventricular myocytes or NRVMs (neonatal rat ventricular myocytes) respectively, and by co-immunoprecipitation of FHL1 and FHL2 with GFP-PKD1 fusion protein expressed in NRVMs. In vitro kinase assays showed that neither FHL1 nor FHL2 is a PKD1 substrate.

SUBMITTER: Stathopoulou K 

PROVIDER: S-EPMC3927927 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature