Transcription factor USF2 is developmentally regulated in fetal lung and acts together with USF1 to induce SP-A gene expression

In the present study, proximal binding element (PBE) was used to screen a rabbit fetal lung cDNA expression library; a cDNA insert encoding the structurally related rabbit upstream stimulatory factor-2 (rUSF2) was isolated. We suggest that heterodimers of USF2 and USF1 bound to two E-box elements in the SP-A gene 5'-flanking region serve a key role in developmental and hormonal regulation of SP-A gene expression in pulmonary type II cells.