UMMS Affiliation
Department of Physiology
Publication Date
2007-10-26
Document Type
Article
Subjects
Myosin Type II; Actins; Cytokinesis; Signal Transduction
Disciplines
Life Sciences | Medicine and Health Sciences
Abstract
Equatorial organization of myosin II and actin has been recognized as a universal event in cytokinesis of animal cells. Current models for the formation of equatorial cortex favor either directional cortical transport toward the equator or localized de novo assembly. However, this process has never been analyzed directly in dividing mammalian cells at a high resolution. Here we applied total internal reflection fluorescence microscope (TIRF-M), coupled with spatial temporal image correlation spectroscopy (STICS) and a new analytical approach termed temporal differential microscopy (TDM), to image the dynamics of myosin II and actin during the assembly of equatorial cortex. Our results indicated distinct and at least partially independent mechanisms for the early equatorial recruitment of myosin and actin filaments. Cortical myosin showed no detectable directional flow during early cytokinesis. In addition to equatorial assembly, we showed that localized inhibition of disassembly contributed to the formation of the equatorial myosin band. In contrast to myosin, actin filaments underwent a striking flux toward the equator. Myosin motor activity was required for the actin flux, but not for actin concentration in the furrow, suggesting that there was a flux-independent, de novo mechanism for actin recruitment along the equator. Our results indicate that cytokinesis involves signals that regulate both assembly and disassembly activities and argue against mechanisms that are coupled to global cortical movements.
DOI of Published Version
10.1091/mbc.E07-08-0783
Source
Mol Biol Cell. 2008 Jan;19(1):318-26. Epub 2007 Oct 24. Link to article on publisher's site
Journal/Book/Conference Title
Molecular biology of the cell
Related Resources
PubMed ID
17959823
Repository Citation
Zhou, Mian and Wang, Yu-Li, "Distinct Pathways for the Early Recruitment of Myosin II and Actin to the Cytokinetic Furrow" (2007). Open Access Articles. 1318.
https://escholarship.umassmed.edu/oapubs/1318