MIRANDA IS REQUIRED FOR THE ASYMMETRIC LOCALIZATION OF PROSPERO DURING MITOSIS IN DROSOPHILA

Asymmetric division of Drosophila neuroblasts, sensory organ precursor cells, and cells in the procephalic neurogenic region involves the se gregation of Numb and Prospero proteins into one of the two daughter c ells. We have isolated a novel gene, miranda, based on the ability of its gene product to interact with the Prospero asymmetric localization domain. miranda expression coincides spatially and temporally with as ymmetric cell divisions and asymmetric localization of Prospero. Miran da protein is localized asymmetrically, along with Prospero, to the ba sal cell membrane during mitosis. Loss of miranda gene function abolis hes asymmetric Prospero localization during mitosis. The asymmetric lo calization of Miranda protein requires inscuteable. Our results sugges t that miranda functions downstream of inscuteable and works as an ada pter that connects Prospero to the basal cell membrane during asymmetr ic cell division.