(Alliance, FBgn0003124 )

May play a role in regulating both nuclear and cytoplasmic aspects of the mitotic cycle (PubMed:1660828). Regulates localization of the augmin complex during mitosis by ensuring its location on mitotic spindles (PubMed:24829288). Also regulates augmin complex localization during male meiosis by promoting its placement at kinetochores while preventing its association with spindle microtubules (PubMed:24829288).

(UniProt, P52304)

Maternal-effect mitotic mutation and male meiotic mutation. The wild type allele functions in the early embryo and in the imaginal and neuroblast cells of the larva. About 7% of polo1 homozygotes (offspring of polo1/+ females mated to polo1/+ or polo1/polo1 males) survive to adulthood, but most of them die as late third instar larvae, their imaginal disks and neuroblast cells failing to proliferate. polo2 homozygotes (offspring of polo2/+ females mated to polo2/+ males) never eclose, dying as early third-instar larvae. Some polo1/polo2 heterozygotes (less than 7%) survive, but show very abnormal cuticle formation in the abdominal tergites. Offspring of surviving polo1/polo1 females die very early in development, the embryos showing an abnormal distribution of nuclei that fail to cellularize and then become polyploid before breaking down. Spindles of these embryonic nuclei are highly branched and have broad, barrel-shaped poles. In third instar larvae homozygous for polo1, many of the neuroblast cells show mitotic abnormalities. In anaphase, the chromosomes are often in a circular arrangement and may or may not be polyploid or aneuploid; these chromosomes, however, are never fragmented and seem to undergo normal condensation. In anaphase, chromosomes frequently lie in a random orientation at one or both poles. Surviving polo1/polo1 males are fertile, but often show meiotic abnormalities. Many of the meiotic spindles are irregular in shape and structure amd a high frequency of nondisjunction occurs, mostly in the second meiotic division.