The PAR-aPKC system: lessons in polarity.
Ten years ago, par-1 and par-3 were cloned as two of the six par genes essential for the asymmetric division of the Caenorhabditis elegans zygote. PAR-1 is a protein kinase, whereas PAR-3 is a PDZ-domain-containing scaffold protein. Work over the past decade has shown that they are part of an evolutionarily conserved PAR-aPKC system involved in cell polarity in various biological contexts. Recent progress has illustrated the common principle that the PAR-aPKC system is the molecular machinery that converts initial polarity cues in the establishment of complementary membrane domains along the polarity axis. In most cases, this is achieved by mutually antagonistic interactions between the aPKC-PAR-3-PAR-6 complex and PAR-1 or PAR2 located opposite. However, accumulating evidence has also revealed that mechanisms by which the asymmetrically localized components of the PAR-aPKC system are linked with other cellular machinery for developing polarity are divergent depending on the cell type.
Suzuki
Atsushi
A
Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fuku-ura, Kanazawa-ku, Yokohama 236-0004, Japan. abell@med.yokohama-cu.ac.jp
Ohno
Shigeo
S
D048948:14-3-3 Proteins / Q000502:physiology; D000818:Animals; D051186:Armadillo Domain Proteins / Q000378:metabolism; D017173:Caenorhabditis elegans; D029742:Caenorhabditis elegans Proteins / Q000502:physiology*; D016764:Cell Polarity / Q000502:physiology*; D004330:Drosophila; D029721:Drosophila Proteins / Q000502:physiology; D007365:Intercellular Junctions / Q000502:physiology; D008870:Microtubules / Q000502:physiology; D011485:Protein Binding; D011493:Protein Kinase C / Q000502:physiology*; D017346:Protein Serine-Threonine Kinases / Q000502:physiology; D011506:Proteins / Q000502:physiology*; D015398:Signal Transduction
D048948:14-3-3 Proteins; D051186:Armadillo Domain Proteins; D029742:Caenorhabditis elegans Proteins; D029721:Drosophila Proteins; D011506:Proteins; C087977:par-2 protein, C elegans; C106207:par-5 protein, C elegans; C512642:par-6 protein, C elegans; C409406:PAR-1 protein, C elegans; C097238:PAR-3 protein, C elegans; D017346:Protein Serine-Threonine Kinases; C115015:PKC-3 protein; D011493:Protein Kinase C