K + LOCALIZATION IN MUSCLE CELLS BY AUTORADIOGRAPHY, AND IDENTIFICATION OF K + ADSORBING SITES IN LIVING MUSCLE CELLS WITH URANIUM BINDING SITES IN ELECTRON MICROGRAPHS OF FIXED CELL PREPARATIONS

Localization of K+-adsorption sites on two peripheral regions of the A band and the Z line in frog voluntary muscle cells has been dernonstrated with the aid of autoradiography and radioactive l 3 T s arzd 20(Tl, The findings confirm the association-induction hypothesis, according to which intracellular K+ is adsorbed on the /3- and y-carboxyl groups oj intracellrilar proteins