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PubMed · 389627

F-Actin-depolymerizing activity of human serum.

R Norberg·R Thorstensson·G Utter·A Fagraeus
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Abstract

Non-heated human and animal sera contain a factor which exhibited an inhibiting activity on the staining of actin-containing structures by anti-actin antibodies in indirect immunofluorescence experiments. The presence of this factor lowered the viscosity of F-actin preparations and caused, as studied by electron-microscopy, a depolymerization of F-actin filaments as well as inhibition of filament formation of G-actin. The factor was, after its reaction with F-actin, liberated seemingly unaffected, indicating an enzymatic activity. The factor tentatively termed 'F-actin depolymerizing factor' was heat-sensitive and trypsin sensitive but resisted reduction. It was Ca2+ dependent and the staining inhibiting reaction was faster at 30 degrees C and 37 degrees C than at lower temperatures. Gel filtration experiments on Sephadex G-200 suggested a molecular size of the actin depolymerizing factor slightly higher than that of albumin. The electrophoretic mobility was that of gamma 2 globulin. The physiological role of the factor might be to prevent the presence of F-actin filaments within the circulation.

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ActinsAnimalsAntibodiesFluorescent Antibody TechniqueHumansHyperthyroidismKidneyLiverMacromolecular SubstancesMusclesOrgan SpecificityRatsStomachThyroid GlandJournal Article

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R Norberg, R Thorstensson, G Utter, A Fagraeus. 1979-10-15. F-Actin-depolymerizing activity of human serum.. https://doi.org/10.1111/j.1432-1033.1979.tb04204.x

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