Par6? is at the mother centriole and controls centrosomal protein composition through a Par6?-dependent pathway.

ABSTRACT: The centrosome contains two centrioles that differ in age, protein composition and function. This non-membrane bound organelle is known to regulate microtubule organization in dividing cells and ciliogenesis in quiescent cells. These specific roles depend on protein appendages at the older, or mother, centriole. In this study, we identified the polarity protein partitioning defective 6 homolog gamma (Par6?) as a novel component of the mother centriole. This specific localization required the Par6? C-terminus, but was independent of intact microtubules, the dynein/dynactin complex and the components of the PAR polarity complex. Par6? depletion resulted in altered centrosomal protein composition, with the loss of a large number of proteins, including Par6? and p150(Glued), from the centrosome. As a consequence, there were defects in ciliogenesis, microtubule organization and centrosome reorientation during migration. Par6? interacted with Par3 and aPKC, but these proteins were not required for the regulation of centrosomal protein composition. Par6? also associated with Par6?, which controls protein recruitment to the centrosome through p150(Glued). Our study is the first to identify Par6? as a component of the mother centriole and to report a role of a mother centriole protein in the regulation of centrosomal protein composition.

SUBMITTER: Dormoy V 

PROVIDER: S-EPMC3619814 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature