Gamma-tubulin complex is necessary for microtubule nucleation at the microtubule organizing centers (MTOCs). Required for the positioning of the gamma-tubulin-containing complex on pre-existing microtubules and for the proper organization of cortical arrays. Gamma-tubulin complex is essential for the control of microtubular network remodeling in the course of initiation and development of giant-feeding cells, and for the successful reproduction of nematodes (e.g. Meloidogyne spp.) in their plant hosts. Part of the gamma-tubulin complex. Gamma-tubulin complex is composed of gamma-tubulin and GCP proteins. Interacts directly with GCP2, GIP1 and GIP2. Associated to motile complexes in the cytosol that transiently stabilized at fixed locations in the cell cortex (e.g. along the outer periclinal edge of newly formed crosswalls) from which microtubules grow away prior to microtubules nucleation. Colocalizes with gamma-tubulin at the nuclear surface where microtubules are nucleated. Localizes to both cortical cytoplasm and mitotic microtubule arrays of the nematode feeding giant cells. Up-regulated in galls upon nematode infection. Belongs to the TUBGCP family.