A myosin I isoform in the nucleus.
A nuclear isoform of myosin I beta that contains a unique 16-amino acid amino-terminal extension has been identified. An affinity-purified antibody to the 16-amino acid peptide demonstrated nuclear staining. Confocal and electron microscopy revealed that nuclear myosin I beta colocalized with RNA polymerase II in an alpha-amanitin- and actinomycin D-sensitive manner. The antibody coimmunoprecipitated RNA polymerase II and blocked in vitro RNA synthesis. This isoform of myosin I beta appears to be in a complex with RNA polymerase II and may affect transcription.
Pestic-Dragovich
L
L
Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL 60612, USA.
Stojiljkovic
L
L
Philimonenko
A A
AA
Nowak
G
G
Ke
Y
Y
Settlage
R E
RE
Shabanowitz
J
J
Hunt
D F
DF
Hozak
P
P
de Lanerolle
P
P
D016475:3T3 Cells; D000199:Actins / Q000378:metabolism; D000546:Amanitins / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism*; D003001:Cloning, Molecular; D003609:Dactinomycin / Q000494:pharmacology; D005091:Exons; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D018613:Microscopy, Confocal; D008854:Microscopy, Electron; D020409:Molecular Motor Proteins; D008969:Molecular Sequence Data; D009218:Myosins / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology; D011233:Precipitin Tests; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D012313:RNA / Q000096:biosynthesis*; D012319:RNA Polymerase II / Q000378:metabolism*; D014158:Transcription, Genetic
D000199:Actins; D000546:Amanitins; D020409:Molecular Motor Proteins; D019384:Nucleic Acid Synthesis Inhibitors; D020033:Protein Isoforms; D003609:Dactinomycin; D012313:RNA; D012319:RNA Polymerase II; D009218:Myosins