The Centrosome Regulates the Rab11- Dependent Recycling Endosome Pathway at Appendages of the Mother Centriole

Abstract

Summary The recycling endosome localizes to a pericentrosomal region via microtubule-dependent transport. We previously showed that Sec15, an effector of the recycling endosome component, Rab11-GTPase, interacts with the mother centriole appendage protein, centriolin, suggesting an interaction between endosomes and centrosomes (1, 2). Here we show that the recycling endosome associates with the appendages of the mother (older) centriole. We show that the mother centriole appendage proteins, centriolin and cenexin/ODF2, regulate association of the endosome components Rab11, the Rab11 GTP-activating protein Evi5, and the exocyst at the mother centriole. Development of an in vitro method for reconstituting endosome protein complexes onto isolated membrane-free centrosomes demonstrates that purified GTP-Rab11 but not GDP-Rab11 binds to mother centriole appendages in the absence of membranes. Moreover, centriolin depletion displaces the centrosomal Rab11 GAP, Evi5, and increases mother-centriole-associated Rab11; depletion of Evi5 also increases centrosomal Rab11. This indicates that centriolin localizes Evi5 to centriolar appendages to turn off centrosomal Rab11 activity. Finally, centriolin depletion disrupts recycling endosome organization and function suggesting a role for mother centriole proteins in the regulation of Rab11 localization and activity at the mother centriole.

The deubiquitinating enzyme CYLD controls apical docking of basal bodies in ciliated epithelial cells

“…However, we cannot rule out that ubiquitination/deubiquitination processes might affect centriole appendages and centriolar satellite functions 59,60 .…”

A new role for Rab GTPases during early mitotic stages

“…3,4 The mother centriole also templates cilia formation 5 and regulates membrane recycling through Rab11. 2 The role of the mother centriole was further identified to modulate Rab11-activity through organization of recycling endosome machinery. 2 If appendages were disrupted, recycling endosome machinery (e.g., the exocyst and the Rab11 GTPase Activating Protein, EVI5) were dispersed.…”

“…2 The role of the mother centriole was further identified to modulate Rab11-activity through organization of recycling endosome machinery. 2 If appendages were disrupted, recycling endosome machinery (e.g., the exocyst and the Rab11 GTPase Activating Protein, EVI5) were dispersed. 2 However, what this study did not demonstrate was whether recycling endosomes contributed to the organization and function of the centrosome.…”

“…However, a direct relationship between these intracellular elements remained unclear until 2012 when electron microscopy revealed an intimate interaction with a substructure of the centrosome, the mother centriole appendages. 2 Mother centriole appendages have become a focus of interest because they functionally define the "older" centriole of the centriole pair. This has important consequences in biology.…”

“…2 If appendages were disrupted, recycling endosome machinery (e.g., the exocyst and the Rab11 GTPase Activating Protein, EVI5) were dispersed. 2 However, what this study did not demonstrate was whether recycling endosomes contributed to the organization and function of the centrosome. A follow-up study went on to show that the recycling endosome contributes to the organization of the mitotic spindle poles and organization of the spindle.…”