Required for gamma-tubulin complex recruitment to the microtubule organizing centers (MTOCs) (By similarity). During mitosis, modulates gamma-tubulin complex localization, spindle stability and chromosomal segregation. Necessary for gametophyte development and embryogenesis. Part of the gamma-tubulin complex. Interacts with GIP1 and GCP3. Reorganized from the nucleus to the prospindle and the preprophase band in late G2. After nuclear envelope breakdown, localized on spindle and phragmoplast microtubules (MTs) and on the reforming nuclear envelope of daughter cells. Present in mitotic microtubule arrays. In interphase cortical arrays, gamma-tubulin complexes are preferentially recruited to existing microtubules, from which new microtubules are efficiently nucleated. Mostly expressed in siliques and flowers, and, to a lower extent, in leaves, roots and seedlings, with highest levels in young tissues, meristematic cells, and the vasculature. In the gip1 gip2 double mutants, embryonic lethality and impaired development of male gametophytes, severe growth defects and sterility, characterized by microtubule (MT) misorganization and abnormal spindle polarity, resulting in ploidy defects. Belongs to the MOZART1 family.