Characterization of acidic actin in mouse sarcoma 180 cells.
Mouse sarcoma 180 cells have a polypeptide that has the same molecular weight as actin but it is more acidic than alpha-actin. Its tryptic peptide pattern on reversed-phase HPLC was very similar to that of beta + gamma-actin, an actin sample prepared by affinity chromatography on DNase I-Sepharose contained the acidic polypeptide, and monoclonal anti-actin antibody reacted with it; therefore, the polypeptide is considered an actin isoform. The mRNA for this variant actin was identified by analyzing the polypeptides translated in vitro, which indicated that the variant actin is not a post-translationally modified form of any known actin. The variant actin was not stained by polyclonal anti-gizzard actin antibody which reacts with gamma-cytoplasmic, alpha-smooth and gamma-smooth muscle actins, nor by polyclonal anti-skeletal muscle actin antibody which reacts with skeletal, cardiac and alpha-smooth muscle actins. These results suggest that this variant actin is related to beta-cytoplasmic actin or, is a novel species whose N-terminal amino acid sequence is not Glu-Glu-Glu.
Ueyama
H
H
Department of Medical Biochemistry, Shiga University of Medical Science, Ohtsu, Japan.
Kurokawa
K
K
Sasaki
I
I
Ueda
K
K
D000199:Actins / Q000032:analysis* / Q000235:genetics; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D014644:Genetic Variation; D051379:Mice; D010446:Peptide Fragments / Q000032:analysis; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D012510:Sarcoma 180 / Q000032:analysis* / Q000378:metabolism
D000199:Actins; D010446:Peptide Fragments; D012333:RNA, Messenger