Centriolar satellites are sites of translation of centrosomal and ciliary proteins

Centriolar satellites are cytoplasmic particles found in the vicinity of centrosomes and cilia whose functional contribution to the formation of these cellular structures has long been unclear. By characterizing the main scaffolding component of satellites, PCM1 or Combover inDrosophila, we show that satellites are not involved in cellular trafficking as previously thought but rather act as sites for the coordinate translation of centrosomal and ciliary proteins through the interaction with a set of RNA binding proteins and proteins involved in quality control. Strikingly, the concentration of satellites near centrosomes and cilia in vertebrates is not a conserved feature and therefore dispensable for satellite function. Such coordinate synthesis may be a general feature in eukaryotic cells to facilitate protein complex formation and cellular compartmentalization.