The product of par-4, a gene induced during apoptosis, interacts selectively with the atypical isoforms of protein kinase C.
The atypical PKCs are involved in a number of important cellular functions, including cell proliferation. We report here that the product of the par-4 gene specifically interacts with the regulatory domains of zeta PKC and lambda/LPKC, which dramatically inhibits their enzymatic activity. This is particularly challenging, because expression of par-4 has been shown to correlate with growth inhibition and apoptosis. Results are shown here demonstrating that the expression of par-4 in NIH-3T3 cells induces morphological changes typical of apoptosis, which are abrogated by cotransfection of either wild-type zeta PKC or lambda/LPKC, but not by their respective kinase-inactive mutants. These findings support a role for the atypical PKC subspecies in the control of cell growth and survival.
Pubmed ID: 8797824 RIS Download
3T3 Cells | Amino Acid Sequence | Animals | Apoptosis | Apoptosis Regulatory Proteins | Bacterial Proteins | Base Sequence | Carrier Proteins | Cell Line | Cercopithecus aethiops | Cloning, Molecular | Enzyme Inhibitors | Humans | Intracellular Signaling Peptides and Proteins | Isoenzymes | Mice | Molecular Sequence Data | Promoter Regions, Genetic | Protein Binding | Protein Kinase C | Protein-Serine-Threonine Kinases | Proto-Oncogene Proteins | Proto-Oncogene Proteins c-mos | Proto-Oncogene Proteins c-raf | Recombinant Fusion Proteins | Sequence Alignment | Sequence Homology, Amino Acid | Serine Endopeptidases | Zinc Fingers