Metaphase to anaphase transition is delayed in aurA¹⁷⁹⁶¹/aurA¹⁴⁶⁴¹ transheterozygous larval brain neuroblasts.

Mutants show a massive increase in larval brain neuroblasts, developing more than 1000 central brain neuroblasts at stages where wild-type larvae have only 95-100 neuroblasts. The mutant neuroblasts are proliferative and can generate neuronal progeny. The orientation of the mitotic spindle is essentially randomised relative to the apical/basal cortical polarity axis in mutant metaphase neuroblasts, in contrast to wild-type metaphase neuroblasts where the mitotic spindle is aligned within 15⁰ of the center of the apical/basal cortical polarity axis.

Single cell mutant clones induced in a single neuroblast typically generate a clone containing multiple neuroblasts as well as a pool of smaller ganglion mother cell(GMC)/neuronal progeny, in contrast to single cell wild-type clones which give rise to one large neuroblast and a population of smaller GMC/neuronal progeny.

Mutant pupal sensory organ precursor (SOP) cells show nearly random spindle orientation relative to the cortical polarity axis, in contrast to wild-type SOP cells.

Mutant neuroblasts in explanted larval brains show both asymmetric and symmetric (17%) cell divisions, in contrast to wild-type controls which always divide asymmetrically.

Homozygous larvae have supernumerary neuroblasts.