pericentriolar

Pericentriolar is an adjective describing the region surrounding the centrosome. In most animal cells, this area contains the pericentriolar material (PCM), a dynamic, non-membranous protein matrix that envelops the pair of centrioles and serves as the principal microtubule organizing center during interphase and mitosis.

The PCM houses key microtubule-nucleating complexes, most notably the gamma-tubulin ring complexes, and a network of scaffolding and regulatory proteins such as pericentrin, CDK5RAP2 (CEP215), CEP192, and CEP152. Together, these components recruit and organize microtubule nucleation sites, anchor microtubule minus ends, and help assemble the bipolar spindle by positioning the centrosomes.

PCM composition and size are dynamic across the cell cycle. Centrosome maturation involves recruitment of additional PCM, expanding its capacity to nucleate microtubules as cells enter mitosis. This maturation is regulated by cell cycle kinases such as Polo-like kinases and Cdk1.

Defects in PCM proteins or centrosome amplification can disrupt spindle formation and genomic stability, with reported associations to cancer and developmental disorders such as microcephaly. The concept of pericentriolar material is primarily used in studies of animal cells, while other organisms may show variation in centrosome structure.