Colocalization of ${\alpha}$of Gq Protein with Actin Filaments in L8E63 Cells

  • Chae, Sungsuk (Department of Life Science, Kwang-ju Institute of Science and Technology) ;
  • Park, Dongeun (Department of Life Science, Kwang-ju Institute of Science and Technology)
  • Published : 1997.03.01

Abstract

The present study investigated the cellular localization of a-subunit of Gq (Gaq) protein in developing L8E63, rat skeletal muscle cell line. The colocalization of Gaq with actin cytoskeleton was demonstrated by double-labeling experiments. In mononucleated myoblasts, the immuno-fluorescence staining pattern of Gaq was almost identical with that of F-actin visualized with rhodamine-conjugated phalloidin. However, this colocalization of Gaq with cytoskeleton was not maintained in multinucleated myotubes. The staining pattern of Gaq in myotubes did not match with any specific subcellular structure, but appeared as a uniformly distributed diffuse staining throughout the whole cell surface. Interestingly, change in the expression level of Gaq was not detected during myoblast differentiation, suggesting that actin-associated Gaq protein might dissociate from the cytoskeleton as cells differentiate. Immunocytochemical experiments using specific antibodies directed against several G proteins indicated that the subcellular localizations of Gai1, Gai2, Gai3, and Gao were different from those obtained with Gaq.

Keywords

References

  1. Cell v.71 Receptor to signaling through G proteins; roles for βγ dimers as α subunits Birnbaumer L
  2. J Biol Chem v.266 Purification and characterization of two G-proteins that activate the β1 isozyme of phosphoinositide-specific phospholipase C. Identification as members of the Gq class Blank JL;Ross AH;Exton JH
  3. J Immunol v.144 Interactions between a lymphoma membrane-associated GTP-binding protein and the cytoskeleton during receptor patching and capping Bourguignon LYM;Wallker G;Huang HS
  4. Mol Pharmacol v.30 Fractionation of the β sucunit common to guanine nucleotide-binding regulatory proteins with the cytoskeleton Calson KE;Woolkalis MJ;Newhouse MG;Manning DR
  5. Proc Natl Acad Sci USA v.89 Heterotrimeric G proteins in synaptoneurosom membranes are crosslinked by p-pheny-Ienedimaleimide, yielding structures comparable in size to crosslinked tubulin and F-action Coulter S;Rodbell M
  6. Curr Opin Cell Biol v.8 Assembly of focal adhesions; progress, paradigms, and portents Craig SW;Johnson RP
  7. Science v.247 The actin-binding protein profilin binds to $PIP_2$ and inhibits its hydrolysis by phospholipase C Goldschmidt-Clermont PJ;Machesky LM;Baldassare JJ;Pollard TD
  8. Mol Pharmacol v.43 Compartmentation of receptor and guaniae nucleotide-binding proteins in NG108-15 cells; lack of cross-talk in agonist binding among the α2 -adrenergic, muscarinic, and opiate receptors Graeser D;Neubig RR
  9. Proc Natl Acad Sci USA v.92 Close association of the α subunits of Gq and G11 G proteins with actin filaments in WRK1 cells; Relation to G proteinmediated phospholipase C activation Ibarrondo J;Joubert D;Dufour MN;Cohen-Solal A;Homburger V;Jard S;Guilon G
  10. J Biol Chem v.286 Cloning, sequencing, purification, and Gq-dependent activation of phospholipase C-β3 Jhon DY;LeeH-H;ParkD;LeeC-W;LeeK-H;YooOJ;RheeSG
  11. Curr Opin Cell Biol v.7 Significance of PIP2 hydrolysis and regulation of phoapholipase C isozymes LeeSB;RheeSG
  12. J Biol Chem v.268 Alteration in Gs-mediated signal transduction in S49 lymphoma cells treated with inhibitors of microtubules Leiber D;Jasper JR;Alousi AA;Martin J;Bernstein D;Insel PA
  13. Science v.258 Cytoskeleton-plasma membrance interactions Luna EJ;Hitt AL
  14. Curr Opin Cell Biol v.7 Lysophosphatidic acid signaling Moolenaar WH
  15. J Biol Chem v.264 Possilble involvement of cytoskeleton in collagen-stimulated activation of phospholipases in human platelets NakanoT;HanasakiK;AritaH
  16. Cell v.80 Heterotrimeric G proteins;Organizers of transmembrane signals Neer EJ
  17. J Cell Biol v.105 Regulation of the affinity atate of the N-formylated peptide receptor of neutrophils; role of GTP-binding proteins and the cytoskeleton Painter RG;Zahler-Bentz K;Dukes RE
  18. J Biol Chem v.267 Regulation of inositol phospholipid-specific phospholipase C isozymes RheeSG;ChoiKD
  19. Proc Natl Acad Sci v.90 Stimulus-induced dissociation of subunits of heterotrimeric GTP-binding proteins from the cytoskeleton of human neutrophils Sarndahal E;Bokoch GM;Stendahl O;Andersson T
  20. Science v.252 Diversity of G proteins in signal transduction Simon MI;Strathmann MP;Gautam N
  21. Science v.251 Regulation of polyphosphoinsitide-specific phospholipase C activity by purified Gq Smrcka AV;Hepler JR;Brown KO;Sternweis PC
  22. J Biol Chem v.267 Association of a receptor and G protein-regulated phospholipase C with the cytoskeleton Vaziri C;Downes CP
  23. Endocrinology v.134 Cellular variations in heterotrimeric G protein localization and expression in rat pituitary Wilson BS;Komoru M;Farquhar MG
  24. J Biol Chem v.269 Epidermal growth factor-induced activation and translation of phospholipase C-γ1 to the cytoskeleton in rat hepatocytes Yang LJ;Rhee SG;Williamson JR