Thymocyte Selection Is Regulated by the Helix-Loop-Helix Inhibitor Protein, Id3 (original) (raw)

Department of Biology, 0366 et al., 1996). T cell-specific E box binding complexes University of California, San Diego are largely composed of heterodimers of E2A and HEB La Jolla, California 92093 (Sawada and Littman, 1993; Bain et al., 1997). Targeted disruption of the HEB or E2A genes leads to severe defects in thymocyte development (Zhuang et al., 1996; Summary Bain et al., 1997). E2A-deficient mice lack subsets of ␥␦ T cells, due in part to an impaired ability to undergo E2A, HEB, E2-2, and daughterless are basic helix-TCR V(D)J recombination (Bain et al., 1999a). E2A null loop-helix (bHLH) proteins that play key roles in multimutant mice also show a partial block at the doubleple developmental pathways. The DNA binding activity negative (DN) stage, prior to the onset of TCR␤ chain of E2A, HEB, and E2-2 is regulated by a distinct class gene rearrangement (Bain et al., 1997). In addition, E2Aof inhibitor HLH proteins, the Id gene products. Here, deficient thymocytes exhibit a