Transcriptional activity of WASP-CAT mutant constructs bearing mutations in the proximal (W-CAT-▵EtsP), distal (W-CAT-▵EtsD), or in both Ets binding sites (W-CAT-▵EtsP/▵EtsD). CAT activity is expressed as percentage of the wild-type construct, W-CAT-5′▵-137.