Nuclear-localized calcineurin homologous protein CHP1 interacts with upstream binding factor and inhibits ribosomal RNA synthesis.

ABSTRACT: Calcineurin homologous protein 1 (CHP1) is a widely expressed, 22-kDa myristoylated EF-hand Ca(2+)-binding protein that shares a high degree of similarity with the regulatory B subunit of calcineurin (65%) and with calmodulin (59%). CHP1 localizes to the plasma membrane, the Golgi apparatus, and the nucleus and functions to regulate trafficking of early secretory vesicles, activation of T cells, and expression and transport of the Na-H exchanger NHE1. Although CHP1 contains nuclear export signals, whether its nuclear and cytoplasmic localization is regulated and has distinct functions remain unknown. We show that CHP1 is predominantly in the nucleus in quiescent fibroblasts, is translocated to cytoplasmic compartments with growth medium, and that translocation is inhibited by mutations in

SUBMITTER: Jimenez-Vidal M 

PROVIDER: S-EPMC2978553 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature