Third instar mspsP18/mspsP18 or mspsP18/mspsP larval central brains have a significant increase in neuroblast number. Extra neuroblasts are found in both type I (Scer\GAL4ase.neuro) and II (Scer\GAL4wor.PA and Scer\GAL80ase.PN) neuroblast lineages in mspsP18/mspsP18 clones. In mspsP18/mspsP18 mutant larval brains, most neuroblasts display random alignment of mitotic spindle, a small percentage show orthogonal division and apicobasal polarity is disrupted. mspsP18/mspsP mutants also show spindle misorientation in metaphase neuroblasts.
mspsP18 is rescued by mspsFL.UAS/Scer\GAL4insc.PU
Expression of mspsFL.Scer\UAS driven by Scer\GAL4insc.PU rescues the phenotype of extra neuroblasts and spindle misorientation in metaphase neuroblasts in mspsP18/mspsP18 larval central brains.