MARK2/Par1b kinase present at centrosomes and retraction fibres correctsspindle off-centring induced by actin disassembly
Published in Open Biology, 2019
Abstract
Tissue maintenance and development requires a directed plane of celldivision. While it is clear that the division plane can be determined by retrac-tion fibres that guide spindle movements, the precise molecular componentsof retraction fibres that control spindle movements remain unclear. Wereport MARK2/Par1b kinase as a novel component of actin-rich retractionfibres. A kinase-dead mutant of MARK2 reveals MARK2’s ability to monitorsubcellular actin status during interphase. During mitosis, MARK2’s localiz-ation at actin-rich retraction fibres, but not the rest of the cortical membraneor centrosome, is dependent on its activity, highlighting a specialized spatialregulation of MARK2. By subtly perturbing the actin cytoskeleton, we revealMARK2’s role in correcting mitotic spindle off-centring induced by actindisassembly. We propose that MARK2 provides a molecular framework tointegrate cortical signals and cytoskeletal changes in mitosis and interphase.