Uni-directional ciliary membrane protein trafficking by a cytoplasmic retrograde IFT motor and ciliary ectosome shedding

eLife

Olivier Belzile¹  Jue Ning¹  Muqing Cao¹  Qian Wang¹  Carmen I Hernandez-Lara¹  William J Snell¹  Yanjie Liu¹  Susan K Dutcher² 

[1] Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, United States;Department of Genetics, Washington University, St. Louis, United States;

关键词: Chlamydomonas;    ciliary signaling;    ciliary ectosome;    intraflagellar transport;    cytoplasmic dynein;    membrane protein trafficking;   

DOI  :  10.7554/eLife.05242

来源: DOAJ

【 摘 要 】

The role of the primary cilium in key signaling pathways depends on dynamic regulation of ciliary membrane protein composition, yet we know little about the motors or membrane events that regulate ciliary membrane protein trafficking in existing organelles. Recently, we showed that cilium-generated signaling in Chlamydomonas induced rapid, anterograde IFT-independent, cytoplasmic microtubule-dependent redistribution of the membrane polypeptide, SAG1-C65, from the plasma membrane to the periciliary region and the ciliary membrane. Here, we report that the retrograde IFT motor, cytoplasmic dynein 1b, is required in the cytoplasm for this rapid redistribution. Furthermore, signaling-induced trafficking of SAG1-C65 into cilia is unidirectional and the entire complement of cellular SAG1-C65 is shed during signaling and can be recovered in the form of ciliary ectosomes that retain signal-inducing activity. Thus, during signaling, cells regulate ciliary membrane protein composition through cytoplasmic action of the retrograde IFT motor and shedding of ciliary ectosomes.

【 授权许可】

Unknown