The mechanism of the phosphorylation-dependent myosin-linked regulation of smooth muscle and nonmuscle myosins is being investigated. We compared the conventional steady-state kinetic analysis of the actin-activated myosin MgATPase activity with the Nitella-based in vitro motility assay which is a quantitative assay for measuring the velocity of myosin-coated beads over an organized substratum of actin, and analyzed the effect of phosphorylation of various sites on the 20,000 Da light chain of smooth muscle and cytoplasmic myosins. We also determined the effect of tropomyosin on the actin-activated myosin MgATPase activity and on the movement of myosin-coated beads.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Intramural Research (Z01)
Project #
1Z01HL001786-10
Application #
3920050
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
10
Fiscal Year
1988
Total Cost
Indirect Cost
Name
U.S. National Heart Lung and Blood Inst
Department
Type
DUNS #
City
State
Country
United States
Zip Code
Young, Gavin; Hundt, Nikolas; Cole, Daniel et al. (2018) Quantitative mass imaging of single biological macromolecules. Science 360:423-427
Bond, Lisa M; Sellers, James R; McKerracher, Lisa (2015) Rho kinase as a target for cerebral vascular disorders. Future Med Chem 7:1039-53
Heissler, Sarah M; Sellers, James R (2015) Four things to know about myosin light chains as reporters for non-muscle myosin-2 dynamics in live cells. Cytoskeleton (Hoboken) 72:65-70
Billington, Neil; Revill, Derek J; Burgess, Stan A et al. (2014) Flexibility within the heads of muscle myosin-2 molecules. J Mol Biol 426:894-907
Kim, Kye-Young; Kawamoto, Sachiyo; Bao, Jianjun et al. (2008) The B2 alternatively spliced isoform of nonmuscle myosin II-B lacks actin-activated MgATPase activity and in vitro motility. Biochem Biophys Res Commun 369:124-34
Sellers, James R; Knight, Peter J (2007) Folding and regulation in myosins II and V. J Muscle Res Cell Motil 28:363-70
Iwamoto, Hiroyuki; Oiwa, Kazuhiro; Kovacs, Mihaly et al. (2007) Diversity of structural behavior in vertebrate conventional myosins complexed with actin. J Mol Biol 369:249-64
Kovacs, Mihaly; Thirumurugan, Kavitha; Knight, Peter J et al. (2007) Load-dependent mechanism of nonmuscle myosin 2. Proc Natl Acad Sci U S A 104:9994-9
Kim, Kye-Young; Kovacs, Mihaly; Kawamoto, Sachiyo et al. (2005) Disease-associated mutations and alternative splicing alter the enzymatic and motile activity of nonmuscle myosins II-B and II-C. J Biol Chem 280:22769-75
Kovacs, Mihaly; Wang, Fei; Hu, Aihua et al. (2003) Functional divergence of human cytoplasmic myosin II: kinetic characterization of the non-muscle IIA isoform. J Biol Chem 278:38132-40

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