Gamma-tubulin complex is necessary for microtubule nucleation at the centrosome. Gamma-tubulin complex is composed of gamma-tubulin, TUBGCP2, TUBGCP3, TUBGCP4, TUBGCP5 and TUBGCP6 (By similarity). Interacts with CDK5RAP2; the interaction is leading to centrosomal localization of TUBTUBGCP3 and CDK5RAP2 (By similarity). Interacts with NIN (via N-terminus); the interaction may promote recruitment of the gamma-tubulin ring complex to the centrosome (PubMed:15784680). Belongs to the TUBGCP family.