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Updated: Jul 13, 2026

A Cell-based Assay to Investigate Non-muscle Myosin II Contractility via the Folded-gastrulation Signaling Pathway in Drosophila S2R+ Cells
Published on: August 19, 2018
Cell cycle regulation of myosin-V by calcium/calmodulin-dependent protein kinase II
R L Karcher1, J T Roland, F Zappacosta
1Department of Cell and Structural Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Abstract:
Organelle transport by myosin-V is down-regulated during mitosis, presumably by myosin-V phosphorylation. We used mass spectrometry phosphopeptide mapping to show that the tail of myosin-V was phosphorylated in mitotic Xenopus egg extract on a single serine residue localized in the carboxyl-terminal organelle-binding domain. Phosphorylation resulted in the release of the motor from the organelle. The phosphorylation site matched the consensus sequence of calcium/calmodulin-dependent protein kinase II (CaMKII), and inhibitors of CaMKII prevented myosin-V release. The modulation of cargo binding by phosphorylation is likely to represent a general mechanism regulating organelle transport by myosin-V.
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