Changes in cellular glycoproteins after transformation: identification of specific glycoproteins and antigens in sodium dodecyl sulfate gels.

Abstract

The glycoproteins of whole cells were analyzed by direct application of radio-iodinated lectins to sodium dodecyl sulfate gels, followed by autoradiography. By use of lectins with different carbohydrate specificities, different sets of glycoproteins were visualized. The most prominent lectin-binding band in many gels is the large, external, transformation-sensitive (LETS) protein. Major glycoprotein differences are revealed when normal and virus-transformed cells are compared. Certain differences are also seen when the glycoproteins are compared from 2 separately derived SV-40 transformants of [mouse embryo] 3T3 cells [SV 3T3 and SV 101 cells], suggesting a degree of clonal variation between these lines that may not relate to transformation. A complementary technique is used to detect specific antigens in sodium dodecyl sulfate gels by direct application of iodinated antibodies. An antiserum specific for the LETS protein is used to identify this antigen in the gels of normal and transformed cells.