May be required for accurate chromosome segregation. Required for proper maturation of seed storage proteins. Forms a complex with MAG2, MIP2 and MIP3 on the endoplasmic reticulum that may be responsible for efficient transport of seed storage proteins. Interacts (via the central region) with MAG2 (PubMed:23025793). Forms a complex with MAG2, MIP2 and MIP3 on the endoplasmic reticulum (PubMed:24118572). In prometaphase, associated with the kinetochore. At metaphase, mostly associated with the spindle. In early anaphase, found in the vicinity of the centromere. As anaphase progresses, dispersed in the cytoplasm. Accumulation of the precursors of the two major storage proteins albumin 2S and globulin 12S in dry seeds. Belongs to the ZW10 family.