Shaggy/GSK-3beta kinase localizes to the centrosome and to specialized cytoskeletal structures in Drosophila.
The assembly of a functional bipolar mitotic spindle requires an exquisite regulation of microtubule behavior in time and space. To characterize new elements of this machinery we carried out a GFP based "protein trap" screen and selected fusion proteins which localized to the spindle apparatus. By this method we identified Shaggy, the Drosophila homologue of glycogen synthase kinase-3beta (GSK-3beta), as a component of centrosomes. GSK-3beta acting in the Wingless signaling pathway is involved in a vast range of developmental processes, from pattern formation to cell-fate specification, and is a key factor for cell proliferation in most animals. We exploited our Shaggy::GFP Drosophila line to analyze the subcellular localizations of GSK-3beta/Shaggy and shed light on its multiple roles during embryogenesis. We found that Shaggy becomes enriched transiently in a variety of specialized cytoskeletal structures of the embryo, including centrosomes throughout mitosis, suggesting that this kinase is involved in the regulation of many aspects of the cytoskeleton function.
Bobinnec
Yves
Y
Biologie du Développement, UMR 7009 CNRS / Université Pierre et Marie Curie, Observatoire Océanologique, Villefranche-sur-mer, France.
Morin
Xavier
X
Debec
Alain
A
D000818:Animals; D049109:Cell Proliferation; D018385:Centrosome / Q000201:enzymology* / Q000502:physiology / Q000648:ultrastructure; D003599:Cytoskeleton / Q000201:enzymology* / Q000502:physiology / Q000648:ultrastructure; D004330:Drosophila / Q000196:embryology / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure; D029721:Drosophila Proteins / Q000378:metabolism*; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D008941:Spindle Apparatus / Q000201:enzymology* / Q000502:physiology / Q000648:ultrastructure; D051155:Wnt1 Protein
D029721:Drosophila Proteins; D011518:Proto-Oncogene Proteins; D051155:Wnt1 Protein; C074622:wg protein, Drosophila; D049452:Green Fluorescent Proteins; C080335:Sgg protein, Drosophila; D038362:Glycogen Synthase Kinase 3