TAL2 Background Information LYL1, TAL1 and TAL2 are part of a family of basic helix-loop-helix (bHLH) proteins implicated in T cell acute leukemia. TAL1 (also designated SCL) is a serine phosphoprotein and basic helix-loop-helix transcription factor known to regulate embryonic hematopoiesis. Lyl-1 (lymphoblastic leukemia derived sequence 1) is a nuclear protein. T-cell acute lymphocytic leukemia-2 protein (TAL2), is involved in T-cell acute lymphoblastic leukemia through a chromosomal translocation involving TAL2 and T-cell receptor beta chain genes. TAL2 includes a helix-loop-helix protein dimerization and DNA binding domain that is homologous to TAL1 and Lyl-1 protooncogenes. In leukemic cells TAL2 exists in both a phosphorylated (pp13TAL2) and an unphosphorylated (p12TAL2) form. A chromosomal aberration involving TAL2 may be a cause of some T-cell acute lymphoblastic leukemia (T-ALL). TAL2 interacts with the E2A proteins (E47 and E12) to form bHLH heterodimers that can bind DNA in a sequence-specific manner.
