title: Direct redox regulation of F-actin assembly and disassembly by Mical.
abstract: Different types of cell behavior, including growth, motility, and navigation, require actin proteins to assemble into filaments. Here, we describe a biochemical process that was able to disassemble actin filaments and limit their reassembly. Actin was a specific substrate of the multidomain oxidation-reduction enzyme, Mical, a poorly understood actin disassembly factor that directly responds to Semaphorin/Plexin extracellular repulsive cues. Actin filament subunits were directly modified by Mical on their conserved pointed-end, which is critical for filament assembly. Mical posttranslationally oxidized the methionine 44 residue within the D-loop of actin, simultaneously severing filaments and decreasing polymerization. This mechanism underlying actin cytoskeletal collapse may have broad physiological and pathological ramifications.
authors: Departments of Neuroscience and Pharmacology and Neuroscience Graduate Program, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
authors: Ruei-Jiun
authors: RJ
authors: Hung
authors: Chi W
authors: CW
authors: Pak
authors: Jonathan R
authors: JR
authors: Terman
mesh_terms: D008841:Actin Cytoskeleton / Q000737:chemistry / Q000378:metabolism*; D000199:Actins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D015815:Cell Adhesion Molecules / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004330:Drosophila; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008715:Methionine / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009249:NADP / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D010084:Oxidation-Reduction; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D011817:Rabbits; D039961:Semaphorins / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D000199:Actins; D015815:Cell Adhesion Molecules; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; C496247:MICAL protein, Drosophila; D009419:Nerve Tissue Proteins; D039961:Semaphorins; C091529:plexin; D009249:NADP; D008715:Methionine