Coatomer-bound Cdc42 regulates dynein recruitment to COPI vesicles

Memorial Sloan-Kettering Cancer Center, New York, New York, United States
The Journal of Cell Biology (Impact Factor: 9.83). 06/2005; 169(3):383-9. DOI: 10.1083/jcb.200501157
Source: PubMed


Cytoskeletal dynamics at the Golgi apparatus are regulated in part through a binding interaction between the Golgi-vesicle coat protein, coatomer, and the regulatory GTP-binding protein Cdc42 (Wu, W.J., J.W. Erickson, R. Lin, and R.A. Cerione. 2000. Nature. 405:800-804; Fucini, R.V., J.L. Chen, C. Sharma, M.M. Kessels, and M. Stamnes. 2002. Mol. Biol. Cell. 13:621-631). The precise role of this complex has not been determined. We have analyzed the protein composition of Golgi-derived coat protomer I (COPI)-coated vesicles after activating or inhibiting signaling through coatomer-bound Cdc42. We show that Cdc42 has profound effects on the recruitment of dynein to COPI vesicles. Cdc42, when bound to coatomer, inhibits dynein binding to COPI vesicles whereas preventing the coatomer-Cdc42 interaction stimulates dynein binding. Dynein recruitment was found to involve actin dynamics and dynactin. Reclustering of nocodazole-dispersed Golgi stacks and microtubule/dynein-dependent ER-to-Golgi transport are both sensitive to disrupting Cdc42 mediated signaling. By contrast, dynein-independent transport to the Golgi complex is insensitive to mutant Cdc42. We propose a model for how proper temporal regulation of motor-based vesicle translocation could be coupled to the completion of vesicle formation.

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Available from: Hediye Erdjument-Bromage, May 22, 2014
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    • "In addition, recruitment of coatomer by a nucleoporin may induce the breakdown of the nuclear envelope (Liu et al. 2003). An interaction of coatomer with cdc42 (Wu et al. 2000) and dynein was attributed to positioning of the Golgi (Chen et al. 2005; Hehnly et al. 2010). "
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    • "Our results are consistent with the hypothesis proposed by others that small GTPases of the ARF and Rho families function coordinately in vivo both at the cell periphery and at the Golgi [4], [42]. Here, we have demonstrated that ARFGAP1 also acts in a bifunctional manner. "
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    • "In addition, various Rho-GTPases have been implicated in intracellular vesicle trafficking. These include Cdc42 that inhibits recruitment of the microtubular motor dynein to COP I-coated Golgi vesicles [66] and RhoA and Rac affecting both clathrin-dependent [67] and clathrin-independent [68] endocytosis. The latter process was recently reported to involve Arf family GTPases that might be linked to the Rho family via GIT proteins, Arfaptins or ARAPs [69]. "
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