FIG. 1.

Expression of Sin isoforms in mature T cells. (A) Schematic structure of Sin, SinII/Efs2, and the truncated protein SinΔC. Y, tyrosine-containing sequences; P, proline-rich motifs; aa, amino acids. (B) Splenocytes (3 × 10⁷) were immunoprecipitated (IP) with Sin-specific or isotype-matched IgG control antibodies, and Western blots of the immune complexes were probed with a Sin-specific monoclonal antibody to reveal expression of the Sin isoforms as indicated. (C) Western blot of splenocytes from two different founders expressing SinΔC probed with anti-Sin (α-Sin) antibody.