Centrobin-centrosomal protein 4.1-associated protein (CPAP) interaction promotes CPAP localization to the centrioles during centriole duplication.
Centriole duplication is the process by which two new daughter centrioles are generated from the proximal end of preexisting mother centrioles. Accurate centriole duplication is important for many cellular and physiological events, including cell division and ciliogenesis. Centrosomal protein 4.1-associated protein (CPAP), centrosomal protein of 152 kDa (CEP152), and centrobin are known to be essential for centriole duplication. However, the precise mechanism by which they contribute to centriole duplication is not known. In this study, we show that centrobin interacts with CEP152 and CPAP, and the centrobin-CPAP interaction is critical for centriole duplication. Although depletion of centrobin from cells did not have an effect on the centriolar levels of CEP152, it caused the disappearance of CPAP from both the preexisting and newly formed centrioles. Moreover, exogenous expression of the CPAP-binding fragment of centrobin also caused the disappearance of CPAP from both the preexisting and newly synthesized centrioles, possibly in a dominant negative manner, thereby inhibiting centriole duplication and the PLK4 overexpression-mediated centrosome amplification. Interestingly, exogenous overexpression of CPAP in the centrobin-depleted cells did not restore CPAP localization to the centrioles. However, restoration of centrobin expression in the centrobin-depleted cells led to the reappearance of centriolar CPAP. Hence, we conclude that centrobin-CPAP interaction is critical for the recruitment of CPAP to procentrioles to promote the elongation of daughter centrioles and for the persistence of CPAP on preexisting mother centrioles. Our study indicates that regulation of CPAP levels on the centrioles by centrobin is critical for preserving the normal size, shape, and number of centrioles in the cell.
From the Departments of Surgery and gudi@musc.edu.
Radhika
R
Gudi
the Department of Medicine, NorthShore Research Institute, Evanston, Illinois 60201.
Chaozhong
C
Zou
the Department of Medicine, NorthShore Research Institute, Evanston, Illinois 60201.
Jayeeta
J
Dhar
the Department of Medicine, NorthShore Research Institute, Evanston, Illinois 60201.
Qingshen
Q
Gao
From the Departments of Surgery and Microbiology and Immunology, Medical University of South Carolina, Charleston, South Carolina 29425 and.
Chenthamarakshan
C
Vasu
D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002455:Cell Division / Q000502:physiology; D002502:Centrioles / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D049452:Green Fluorescent Proteins / Q000235:genetics; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D012516:Osteosarcoma; D010750:Phosphoproteins / Q000378:metabolism; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary; D034741:RNA, Small Interfering / Q000235:genetics
C467559:CCP110 protein, human; C414735:CENPJ protein, human; C551028:CEP152 protein, human; C507203:CNTROB protein, human; D018797:Cell Cycle Proteins; D008869:Microtubule-Associated Proteins; D010750:Phosphoproteins; D034741:RNA, Small Interfering; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; C490219:PLK4 protein, human; D017346:Protein Serine-Threonine Kinases
CEP152; CPAP; Centriole; Centrobin; Centrosome; Cloning; Confocal Microscopy; Gene Expression