THE MURINE TCL1 ONCOGENE - EMBRYONIC AND LYMPHOID-CELL EXPRESSION

In human leukemias and lymphomas nonrandom chromosomal rearrangements cause changes in cell growth and/or survival in such a way as to promo te malignancy, The detailed study of the biochemical and genetic pathw ays altered in human cancer requires the identification or development of models to allow the study and manipulation of cancer gene function , Recently, the breakpoint gene TCL1, involved in chromosome transloca tions observed mostly in mature T-cell proliferations and chronic lymp hocytic leukemias (CLL), was isolated and characterized, and showed to be part of a new gene family of proteins involved in these tumors, Th e murine Tcl1 gene, is similar in sequence to the murine and human MTC P1 gene also involved in T cell leukemias, The murine Tcl1 gene was sh own to reside on mouse chromosome 12 in a region syntenic to human chr omosome 14, Furthermore, we show that the murine Tcl1 gene is expresse d early in mouse embryonic development and demonstrates expression in fetal hematopoietic organs as well as in immature T and B cells, Chara cterization of the murine Tcl1 gene will help in developing a mouse mo del of CLL and would provide the best opportunity to study and deciphe r the role of TCL1 in malignant transformation.