CDK5RAP2 and microcephaly: Astrin is a component of centriolar satellites in interphase, and it is required for the centrosomal localization of CDK5RAP2, a protein involved in microcephaly, and for proper centriole duplication in S phase (Thein et al., 2007; Kodani et al., 2015), a step which is crucial for cell cycle progression.