Figure 8.

Chemical Cross-Linking of ¹²⁵I-Tyr-flg22 to Microsomal Membranes.

Specific labeling of a single 115-kD polypeptide was reproduced in two independent experiments with dithiobis(succinimidyl propionate) and in one experiment with disuccinimidyl suberate as the cross-linkers.

(A) Aliquots of microsomal membranes were incubated with ¹²⁵I-Tyr-flg22 and different concentrations of unlabeled Tyr-flg22 for 30 min on ice. Cross-linking was initiated by addition of dithiobis(succinimidyl propionate), and radiolabeled proteins were analyzed (with a PhosphorImager) after separation by SDS-PAGE. Numbers and dashes at left denote positions and molecular masses in kilodaltons of standard proteins.

(B) Quantitative analysis of radioactivity in the band migrating at 115 kD in (A).