The long-term goal of this project is to understand how cells regulate cellular force production that drives cell migration and other contractile behaviors such as invasion and matrix remodeling. The current submissions focuses on a model of epithelial-to-mesenchymal transition (EMT), in which normal mouse mammary gland cells, which are epithelial in behavior, can be triggered to switch to a mesenchymal, more invasive state in response to the cytokine TGFb. We have recently discovered dramatic regulation of myosin II functions during EMT in this mammary gland model, including nonmuscle myosin II isoform switch, and an upregulation of MHC phosphorylation. Given earlier studies by our group and others documenting MHC phosphorylation as a critical regulator of myosin II filament assembly control during cell migration, our new studies support a model that myosin II isoform switches and MHC phosphorylation may be critical mediators of the enhanced invasive migration behavior and invasiveness that is a hallmark of the switch to the mesenchymal state. We propose a series of cell biological studies to establish the mechanical role of the induced myosin II isoform (myosin IIB), to establish the role of myosin II heavy chain phosphorylation that is induced during EMT, and to identify how cells that go through EMT upregulate myosin II heavy chain phosphorylation. At a broad level, these studies have relevance for understanding how cells upregulate their motility behavior during normal developmental events such as mesoderm initiation and neural tube formation. These studies also have strong relevance to understanding developmental decisions that occur during mammary ductal formation, where cells differentiate towards epithelial versus mesenchymal fates. Finally, these studies have very strong relevance to understanding how cellular contractile/motility machinery is upregulated in pathological settings such as tumor progression to metastatic states and tissue fibrosis.

Public Health Relevance

This project focuses on a fundamental developmental switch, where cells in an epithelial surface sheet detach from each other and become migratory. This process occurs in many settings in embryogenesis, but also during pathological states such as cancer metastasis and lung fibrosis. We see to understanding sub-cellular machinery, known as the actomyosin cytoskeleton that is responsible for migration in these settings. Our studies focus on understanding how cells convert between these states, in particular, how cellular force production is increased to allow migration. Better understanding of this switch to migratory behavior has relevance for many diseases.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
2R01GM050009-19A1
Application #
8629155
Study Section
Intercellular Interactions (ICI)
Program Officer
Gindhart, Joseph G
Project Start
1993-08-01
Project End
2018-04-30
Budget Start
2014-06-01
Budget End
2015-04-30
Support Year
19
Fiscal Year
2014
Total Cost
$378,305
Indirect Cost
$139,627
Name
Cleveland Clinic Lerner
Department
Other Basic Sciences
Type
Schools of Medicine
DUNS #
135781701
City
Cleveland
State
OH
Country
United States
Zip Code
44195
Betapudi, Venkaiah; Egelhoff, Thomas T (2009) Roles of an unconventional protein kinase and myosin II in amoeba osmotic shock responses. Traffic 10:1773-84
Liang, Wenchuan; Licate, Lucila; Warrick, Hans et al. (2002) Differential localization in cells of myosin II heavy chain kinases during cytokinesis and polarized migration. BMC Cell Biol 3:19