however , double-labeling experiments in which plasma membrane , nuclear extract , and cytosol were photolabeled with either [ 125i ] or [ 131i ] t4 and mixed , two at a time , in all possible combinations showed that from one cellular fraction to another , the radioactivity peaks corresponding to the approximately 70- , 43-45- , and 30-kda proteins were not superimposed .
C1383501
cytosol
C0007634
cellular