FIGURE 2.

Identification of the short form of mouse MsrB1. A, metabolic labeling of MsrB1 KO mice with ⁷⁵Se. Wild-type (+/+) and MsrB1 KO (-/-) mice were injected with ⁷⁵Se, and, after 2 days, tissues were extracted and proteins were analyzed by SDS-PAGE, followed by PhosphorImager analysis. Migration of full-length and short forms of MsrB1 is shown by arrows on the left. B, immunoprecipitation of ⁷⁵Se-labeled MsrB1 from mouse liver. MsrB1 was immunoprecipitated from liver extracts of wild-type (+/+, left panel) and MsrB1 KO (-/-, right panel) mice with MsrB1 antibodies. Initial, unbound (flow-through), wash, and eluted fractions were collected and separated by SDS-PAGE, and the labeled protein bands were visualized with a PhosphorImager. Migration of full-length and short forms of MsrB1 is shown by arrows on the left. C, MsrB1 was affinity-isolated from mouse liver extracts on the column containing MsrB1 antibodies and analyzed by immunoblot assays. Migration of full-length and short forms of MsrB1 is shown by the arrows on the left. Molecular weight markers are shown on the right in each panel.