Protein kinase D controls voluntary-running-induced skeletal muscle remodelling.

Skeletal muscle responds to exercise by activation of signalling pathways that co-ordinate gene expression to sustain muscle performance. MEF2 (myocyte enhancer factor 2)-dependent transcriptional activation of MHC (myosin heavy chain) genes promotes the transformation from fast-twitch into slow-twitch fibres, with MEF2 activity being tightly regulated by interaction with class IIa HDACs (histone deacetylases). PKD (protein kinase D) is known to directly phosphorylate skeletal muscle class IIa HDACs, mediating their nuclear export and thus derepression of MEF2.

Protein kinase D controls the integrity of Golgi apparatus and the maintenance of dendritic arborization in hippocampal neurons.

Protein kinase D (PKD) is known to participate in various cellular functions, including secretory vesicle fission from the Golgi and plasma membrane-directed transport. Here, we report on expression and function of PKD in hippocampal neurons. Expression of an enhanced green fluorescent protein (EGFP)-tagged PKD activity reporter in mouse embryonal hippocampal neurons revealed high endogenous PKD activity at the Golgi complex and in the dendrites, whereas PKD activity was excluded from the axon in parallel with axonal maturation.

Expression patterns of protein kinase D 3 during mouse development.

Background: The PKD family of serine/threonine kinases comprises a single member in Drosophila (dPKD), two isoforms in C. elegans (DKF-1 and 2) and three members, PKD1, PKD2 and PKD3 in mammals. PKD1 and PKD2 have been the focus of most studies up to date, which implicate these enzymes in very diverse cellular functions, including Golgi organization and plasma membrane directed transport, immune responses, apoptosis and cell proliferation.

Structural requirements for localization and activation of protein kinase C mu (PKC mu) at the Golgi compartment.

We here describe the structural requirements for Golgi localization and a sequential, localization-dependent activation process of protein kinase C (PKC) mu involving auto- and transphosphorylation. The structural basis for Golgi compartment localization was analyzed by confocal microscopy of HeLa cells expressing various PKC mu-green fluorescent protein fusion proteins costained with the Golgi compartment-specific markers p24 and p230. Deletions of either the NH(2)-terminal hydrophobic or the cysteine region, but not of the pleckstrin homology or the acidic domain, of PKC mu completely abrogated Golgi localization of PKC mu.