Table of Contents
Volume 528 Number 7581 pp163-300
10 December 2015
This Week
News In Focus
Comment
Careers
Specials
Research
About the cover
Scanning electron microscopy images of the mechanosensory organs (or ‘hair’) found on the back of wild-type fruit flies (left). Disruption of asymmetric Sara endosome segregation in a sensitized mutant background changes the cellular fate of stem cells producing these bristles and the back of the fly is then naked (right). Asymmetric cell division in which a cell produces two daughter cells with different cellular fates, is a fundamental process common to stem cells in development and beyond. Many fate determinants are partitioned at the cell cortex during asymmetric division, and in a range of cells, a subset of signalling endosomes segregates unequally in the cytoplasm to mediate the distribution of Notch/Delta signalling molecules between the daughter cells. How this asymmetric distribution is achieved was unknown. Marcos Gonzalez-Gaitan and colleagues now show that, during asymmetric division, central spindle asymmetry is generated by the kinesin Klp10A and its antagonist Patronin, which in turn polarizes the direction of endosome motility. The authors were able to direct the endosome to the wrong cell by inverting the central spindle polarity using an antibody-mediated approach. The system described here is one that can target intracellular cargoes in general, and signalling endosomes in particular, to one of the daughter cells during asymmetric division.
