Drosophila crooked-neck protein co-fractionates in a multiprotein complex with splicing factors.
The Drosophila crooked neck (crn) gene encodes an unusual TPR-containing protein whose function is essential for embryonic development. Homology with other TPR-proteins involved in cell cycle control, initially led to the proposal that Crn might play a critical role in regulation of embryonic cell divisions. Here, we show that Crn does not have a cell cycle function in the embryo. By using specific antibodies we also show that the Crn protein is a nuclear protein which localizes in "speckles" which could correspond to preferential localization of several other splicing factors. Fractionation of nuclear extracts on sucrose gradients revealed Crn in a 900 kDa multiproteic complex together with snRNPs, suggesting that Crn participates in the assembly of the splicing machinery in vivo.
Raisin-Tani
Sophie
S
Institute for Signaling, Developmental Biology and Cancer Research, UMR 6543 CNRS, Centre de Biochimie, Parc Valrose, Nice cedex, France.
Léopold
Pierre
P
D000818:Animals; D002453:Cell Cycle / Q000502:physiology; D002458:Cell Fractionation; D002467:Cell Nucleus / Q000737:chemistry / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology* / Q000502:physiology; D046911:Macromolecular Substances; D046912:Multiprotein Complexes; D009687:Nuclear Proteins / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012326:RNA Splicing
D029721:Drosophila Proteins; D046911:Macromolecular Substances; D046912:Multiprotein Complexes; D009687:Nuclear Proteins; C069204:crn protein, Drosophila