Hedgehog-regulated Costal2-kinase complexes control phosphorylation and proteolytic processing of Cubitus interruptus.
Hedgehog (Hh) proteins control animal development by regulating the Gli/Ci family of transcription factors. In Drosophila, Hh counteracts phosphorylation by PKA, GSK3, and CKI to prevent Cubitus interruptus (Ci) processing through unknown mechanisms. Here, we show that these kinases physically interact with the kinesin-like protein Costal2 (Cos2) to control Ci processing and that Hh inhibits such interaction. Cos2 is required for Ci phosphorylation in vivo, and Cos2-immunocomplexes (Cos2IPs) phosphorylate Ci and contain PKA, GSK3, and CKI. By using a Kinesin-Cos2 chimeric protein that carries Cos2-interacting proteins to the microtubule plus end, we demonstrated that these kinases bind Cos2 in intact cells. PKA, GSK3, and CKI directly bind the N- and C-terminal regions of Cos2, both of which are essential for Ci processing. Finally, we showed that Hh signaling inhibits Cos2-kinase complex formation. We propose that Cos2 recruits multiple kinases to efficiently phosphorylate Ci and that Hh inhibits Ci phosphorylation by specifically interfering with kinase recruitment.
Zhang
Wensheng
W
Center for Developmental Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
Zhao
Yun
Y
Tong
Chao
C
Wang
Gelin
G
Wang
Bing
B
Jia
Jianhang
J
Jiang
Jin
J
D000818:Animals; D030801:Animals, Genetically Modified; D001665:Binding Sites; D047389:Casein Kinase I / Q000235:genetics / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004330:Drosophila / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017344:Genes, Insect; D038362:Glycogen Synthase Kinase 3 / Q000235:genetics / Q000378:metabolism; D053823:Hedgehog Proteins; D016547:Kinesins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008954:Models, Biological; D009154:Mutation; D010641:Phenotype; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors; D014921:Wings, Animal / Q000254:growth & development / Q000378:metabolism
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D053823:Hedgehog Proteins; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; C092937:ci protein, Drosophila; C107452:cos protein, Drosophila; C077245:hh protein, Drosophila; D047389:Casein Kinase I; D017868:Cyclic AMP-Dependent Protein Kinases; D038362:Glycogen Synthase Kinase 3; D016547:Kinesins