Detection and ultrastructural localization of human smooth muscle myosin like molecules in human non muscle cells by specific antibodies

R. G. Painter, Michael Sheetz, S. J. Singer

Research output: Contribution to journalArticle

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Spectrin, a protein complex which is peripherally attached to the cytoplasmic surface of the human erythrocyte membrane, cannot be detected (by complement fixation with anti spectrin antibodies) in homogenates of several different human non muscle cells studied. On the other hand, a protein antigenically identical or similar to human smooth muscle myosin was detected (by complement fixation with antibodies to uterine smooth muscle myosin) in these cells. In the case of human fibroblast line WI38, this smooth muscle myosin like component was shown (by ferritin antibody experiments in electron microscopy) to be at least partly associated with the cytoplasmic surface of the plasma membrane of the cell. It is proposed that the spectrin complex of the erythrocyte membrane and the smooth muscle myosin like component of the fibroblast membrane play similar roles in regulating the translational mobilities of integral proteins in their respective membranes.

Original languageEnglish (US)
Pages (from-to)1359-1363
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number4
StatePublished - Jan 1 1975
Externally publishedYes


ASJC Scopus subject areas

  • General

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