[Features of the preparation and estimation of homogeneity and native state of smooth muscle actin].
It is shown that smooth muscle actin preparations, produced with the help of techniques described in literature, have contaminations of tropomyosin and proteins with the molecular weight of 250 000, 80 000 and 18 000. The composition of contaminations depends on the method of preparation and conditions of dissociation of native actomyosin material. A method is proposed for actin separation from acetone-treated actomyosin followed by salting out with 50 mM MgCl2. Gel-electrophoresis in the presence of Na-dodecylsulphate has shown that the actin preparations are homogeneous and have the same cofactor activity for the myosin ATPase as actin from the rabbit skeletal muscle. It is supposed that in the cytoplasm of smooth muscle cells as well as in the non-muscle ones there is a considerable part of actin is the monomer form. It gets easily lost in the process of fibrillar actin separation. This may account for low actin output in spite of its relatively high contents in smooth muscles.
D000199:Actins / Q000302:isolation & purification*; D000205:Actomyosin / Q000302:isolation & purification; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D008970:Molecular Weight; D009130:Muscle, Smooth / Q000032:analysis*; D009132:Muscles / Q000032:analysis; D009928:Organ Specificity; D011817:Rabbits; D013552:Swine
D000199:Actins; D000205:Actomyosin
Osobennosti polucheniia i otsenka gomogennosti i nativnosti aktina gladkikh myshts.