RT Journal Article
SR Electronic
T1 Spatiotemporally controlled Myosin relocalization and internal pressure cause biased cortical extension to generate sibling cell size asymmetry
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 311852
DO 10.1101/311852
A1 Pham, Tri Thanh
A1 Monnard, Arnaud
A1 Helenius, Jonne
A1 Lund, Erik
A1 Lee, Nicole
A1 Müller, Daniel J.
A1 Cabernard, Clemens
YR 2018
UL http://biorxiv.org/content/early/2018/05/01/311852.abstract
AB Metazoan cells can generate unequal sized sibling cells during cell division. This form of asymmetric cell division depends on spindle geometry and Myosin distribution but the underlying mechanics are unclear. Here, we use atomic force microscopy and live cell imaging to elucidate the biophysical forces involved in the establishment of physical asymmetry in Drosophila neural stem cells. We show that the force driving initial apical membrane expansion is provided by hydrostatic pressure, peaking shortly after anaphase onset, and enabled by a relieve of actomyosin contractile tension on the apical cell cortex. The subsequent increase in contractile forces at the cleavage furrow, combined with the relocalization of basally located Myosin results in basal membrane extension and sustained apical expansion. We propose that spatiotemporally controlled actomyosin contractile tension and hydrostatic pressure enables stereotypic biased membrane expansion to generate sibling cell size asymmetry.