Regulation of B versus T lymphoid lineage fate decision by the proto-oncogene LRF.

Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.
Science (Impact Factor: 31.48). 06/2007; 316(5826):860-6. DOI: 10.1126/science.1140881
Source: PubMed

ABSTRACT Hematopoietic stem cells in the bone marrow give rise to lymphoid progenitors, which subsequently differentiate into B and T lymphocytes. Here we show that the proto-oncogene LRF plays an essential role in the B versus T lymphoid cell-fate decision. We demonstrate that LRF is key for instructing early lymphoid progenitors in mice to develop into B lineage cells by repressing T cell-instructive signals produced by the cell-fate signal protein, Notch. We propose a new model for lymphoid lineage commitment, in which LRF acts as a master regulator of the cell's determination of B versus T lineage.

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