Actin from pig and rat uterus.
Smooth-muscle actin was isolated from pig uterus and from pregnant-rat uterus. Methods involving acetone-dried powders were unsuccessful, and a column-chromatographic procedure was developed, with proteinase inhibitors and avoiding polymerization as a purification step. The yield of pure actin was 0.8--1.5 mg/g wet wt. of uterus, which should be compared with an expected yield of actin from skeletal muscle of 2--4 mg/g wet wt. The actin was pure as judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, and exhibited alpha-, beta-, and gamma-forms on isoelectric focusing. It possessed a blocked N-terminal amino acid residue, and its amino acid analysis conformed to those of other actins. The rat uterine actin was available only in small amounts (5--10 mg) and did not polymerize. The pig uterine actin could be obtained in amounts up to 30 mg, polymerized reversibly, and activated a skeletal myosin Mg2+-dependent ATPase.
D000199:Actins / Q000302:isolation & purification* / Q000494:pharmacology; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D046911:Macromolecular Substances; D011247:Pregnancy; D051381:Rats; D013552:Swine; D014599:Uterus / Q000032:analysis*
D000199:Actins; D000596:Amino Acids; D046911:Macromolecular Substances; D000251:Adenosine Triphosphatases