title: Redox-sensitive residue in the actin-binding interface of myosin.
abstract: We have examined the chemical and functional reversibility of oxidative modification in myosin. Redox regulation has emerged as a crucial modulator of protein function, with particular relevance to aging. We previously identified a single methionine residue in Dictyostelium discoideum (Dicty) myosin II (M394, near the myosin cardiomyopathy loop in the actin-binding interface) that is functionally sensitive to oxidation. We now show that oxidation of M394 is reversible by methionine sulfoxide reductase (Msr), restoring actin-activated ATPase activity. Sequence alignment reveals that M394 of Dicty myosin II is a cysteine residue in all human isoforms of skeletal and cardiac myosin. Using Dicty myosin II as a model for site-specific redox sensitivity of this Cys residue, the M394C mutant can be glutathionylated in vitro, resulting in reversible inhibition of actin-activated ATPase activity, with effects similar to those of methionine oxidation at this site. This work illustrates the potential for myosin to function as a redox sensor in both non-muscle and muscle cells, modulating motility/contractility in response to oxidative stress.
authors.affiliation: Department of Chemistry and Geology, Minnesota State University, Mankato, MN 56001, United States.
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Moen
authors.affiliation: Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States.
authors.forename: Sinziana
authors.initials: S
authors.lastname: Cornea
authors.affiliation: Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Oseid
authors.affiliation: Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States.
authors.forename: Benjamin P
authors.initials: BP
authors.lastname: Binder
authors.affiliation: Department of Biology, University of Wisconsin, Lacrosse, Lacrosse, MN 54601, United States.
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Klein
authors.affiliation: Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States. Electronic address: ddt@umn.edu.
authors.forename: David D
authors.initials: DD
authors.lastname: Thomas
mesh_terms: D000199:Actins / Q000378:metabolism*; D000595:Amino Acid Sequence; D001665:Binding Sites; D020134:Catalytic Domain; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009218:Myosins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010084:Oxidation-Reduction; D017386:Sequence Homology, Amino Acid
chemical_list: D000199:Actins; D009218:Myosins; D005978:Glutathione
keywords: Dictyostelium; Glutathionylation; Methionine; Methionine sulfoxide reductase (Msr); Myosin II; Reactive oxygen species (ROS)