| Abstract: | The calcium-independent mechanism of cell adhesion was studied in normal and polyoma virus-transformed BHK cells. The degree of Ca2+-independent adhesion was greatly reduced in pyBHK cells, whereas CA2+-dependent adhesion occurred to the same degree as in BHK cells. This decrease was shown not to be caused by simple masking of the adhesion sites or by their altered sensitivity to trypsin. Adhesion-blocking antibodies were used to identify molecules responsible for Ca2+-independent adhesion. The antibodies precipitated surface molecules specific for adhesion-competent cells. These have tentatively been named CIDSBHK and CIDSpyBHK. Both were glycoproteins with respective apparent molecular weights of 120K and 125K. CIDSpyBHK incorporated 3H-glucosamine more than CIDSBHK did. Possible modification of the Ca2+-independent adhesion mechanism in pyBHK cells is discussed. |
