FIG. 4.

Oligomer formation of ¹²⁵I-labeled Ib in lipid rafts of MDCK cells. (A) MDCK cells were incubated with ¹²⁵I-labeled Ib at 37°C for the indicated times. Triton X-100-insoluble cell extracts were subjected to SDS-PAGE, followed by autoradiography, as described in Materials and Methods. (B) The radioactivity of the ¹²⁵I-Ib oligomer in MDCK cell lipid rafts was determined by using the Fuji BAS2000 system. The data are the means and standard deviations from three experiments.