to determine whether enhancer elements in addition to the highly conserved octamer ( octa ) -nucleotide motif are important for lymphoid-specific expression of the immunoglobulin heavy-chain ( igh ) gene , we have investigated the effect of mutating the binding site for a putative additional lymphoid-specific transcription factor , designated nf-microb , in the murine igh enhancer .
C0017351
immunoglobulin heavy-chain
C0021034
igh