Effects of aging on DNA-binding activity of the E47 transcription factor in splenic B cells.

In the present paper, we have investigated the DNA-binding activity of the E2A-encoded transcription factor E47 in LPS-activated splenic B cells from young and old BALB/c mice. E47 is a key regulator of B cell differentiation and function: it binds to the E-box site, found in the regulatory regions of several B cell-specific genes (immunoglobulin (Ig), mb-1, and lambda5), promotes cell survival of early pre-B cells, helps to initiate Ig rearrangements, promotes class switch and is perhaps involved in somatic mutation in mature splenic and lymph node B cells. Results show that LPS-stimulated splenic B cells from old mice display decreased E47 DNA-binding activity as compared to young mice and that in splenic activated B cells only E47 homodimers bind DNA.