Characterization of mouse IFT complex B.
The primary cilium plays a key role in the development of mammals and in the maintenance of health. Primary cilia are assembled and maintained by the process of intraflagellar transport (IFT). In this work, we characterize mouse IFT complex B by identifying all of the mammalian orthologues of complex B and B-associated proteins previously identified in Chlamydomonas and Caenorhabditis and also identify a new component (IFT25/Hspb11) of complex B by database analysis. We tagged each of these proteins with the FLAG epitope and show that all except IFT172 and IFT20 localize to cilia and the peri-basal body or centrosomal region at the base of cilia. All of the proteins except IFT172 immunoprecipitate IFT88 indicating that they are co-assembled into a complex. IFT20 is the only complex B protein that localizes to the Golgi apparatus. However, overexpression of IFT54/Traf3ip1, the mouse orthologue of Dyf-11/Elipsa, displaces IFT20 from the Golgi apparatus. IFT54 does not localize to the Golgi complex nor does it interact with GMAP210, which is the protein that anchors IFT20 to the Golgi apparatus. This suggests that IFT54s effect on IFT20 is a dominant negative phenotype caused by its overexpression. Cell Motil. Cytoskeleton 2009. (c) 2009 Wiley-Liss, Inc.
Follit
John A
JA
Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
Xu
Fenghui
F
Keady
Brian T
BT
Pazour
Gregory J
GJ
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D015153:Blotting, Western; D002352:Carrier Proteins / Q000378:metabolism*; D002460:Cell Line; D002923:Cilia / Q000378:metabolism; D003598:Cytoskeletal Proteins; D005407:Flagella / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D047468:Immunoprecipitation; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D051379:Mice; D009687:Nuclear Proteins / Q000378:metabolism; D011485:Protein Binding; D025521:Tumor Suppressor Proteins / Q000378:metabolism
D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; C479520:Ift172 protein, mouse; C514104:Ift20 protein, mouse; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; C534613:TRIP11 protein, mouse; C490898:Tg737Rpw protein, mouse; D025521:Tumor Suppressor Proteins