Paired Box Gene 5 (PAX5)

PAX5 encodes the B-cell lineage specific activator protein (BSAP) that is expressed at early, but not late stages of B-cell differentiation. Its expression has also been detected in developing CNS and testis, therefore, PAX5 gene product may not only play an important role in B-cell differentiation, but also in neural development and spermatogenesis. The PAX5 gene is located in chromosome 9p13 region, which is involved in t(9;14)(p13;q32) translocations recurring in small lymphocytic lymphomas of the plasmacytoid subtype, and in derived large-cell lymphomas. This translocation brings the potent E-mu enhancer of the IgH gene into close proximity of the PAX5 promoters, suggesting that the deregulation of PAX5 gene transcription contributes to the pathogenesis of these lymphomas.