Regulation of microtubule dynamics and myogenic differentiation by MURF, a striated muscle RING-finger protein.
The RING-finger domain is a novel zinc-binding Cys-His protein motif found in a growing number of proteins involved in signal transduction, ubiquitination, gene transcription, differentiation, and morphogenesis. We describe a novel muscle-specific RING-finger protein (MURF) expressed specifically in cardiac and skeletal muscle cells throughout pre- and postnatal mouse development. MURF belongs to the RING-B-box-coiled-coil subclass of RING-finger proteins, characterized by an NH(2)-terminal RING-finger followed by a zinc-finger domain (B-box) and a leucine-rich coiled-coil domain. Expression of MURF is required for skeletal myoblast differentiation and myotube fusion. The leucine-rich coiled-coil domain of MURF mediates association with microtubules, whereas the RING-finger domain is required for microtubule stabilization and an additional region is required for homo-oligomerization. Expression of MURF establishes a cellular microtubule network that is resistant to microtubule depolymerization induced by alkaloids, cold and calcium. These results identify MURF as a myogenic regulator of the microtubule network of striated muscle cells and reveal a link between microtubule organization and myogenesis.
Spencer
J A
JA
Department of Molecular Biology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75235-9148, USA.
Eliazer
S
S
Ilaria
R L
RL
Richardson
J A
JA
Olson
E N
EN
D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D002454:Cell Differentiation; D002460:Cell Line; D015723:Gene Library; D006367:HeLa Cells; D006321:Heart / Q000502:physiology; D006801:Humans; D007930:Leucine; D008297:Male; D051379:Mice; D008870:Microtubules / Q000502:physiology*; D008969:Molecular Sequence Data; D009124:Muscle Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D018482:Muscle, Skeletal / Q000166:cytology / Q000502:physiology*; D009206:Myocardium / Q000378:metabolism; D009928:Organ Specificity; D014176:Protein Biosynthesis; D014158:Transcription, Genetic; D014162:Transfection
D009124:Muscle Proteins; C413644:Rnf30 protein, mouse; C485888:TRIM54 protein, human; D007930:Leucine