Background. During reepithelialization keratinocytes show increased ex
pression of the integrin subunit alpha(v). We have investigated the pr
omoter region of the alpha(v) integrin subunit to learn more about its
regulation. Methods. The promoter region of the human integrin alpha(
v) gene was cloned into a luciferase reporter vector. Deletional mutan
ts were created using PCR. Computerized sequence analysis was performe
d using the Wisconsin Package. Gel shift analysis was performed using
keratinocyte nuclear extracts and oligonucleotides spanning the region
s of interest. Results. Deletion from -522 bp to -235 resulted in no d
iscernible effect on promoter activity. In contrast deletion of the ne
xt 22 bp, which included a putative ets binding site, reduced activity
by approximately half. Further deletion to -139 bp essentially abolis
hed promoter activity. Computer searching of this region of the integr
in alpha(v) promoter revealed two tandemly repeated motifs, TCCTCCTCC,
that had previously been implicated in the function of the epidermal
growth factor receptor (EGFR) promoter. Comparison of the alpha(v), in
tegrin promoter to the EGFR promoter revealed an area of high homology
in this region, Gel-shift analysis revealed binding of a single-stran
d specific DNA binding protein to single-stranded oligos comprising th
ese motifs, but no binding of factors to the double-stranded oligo con
taining the ets binding site. Conclusions. In keratinocytes alpha(v) i
ntegrin expression is controlled by a region of the promoter with high
homology to the epidermal growth factor receptor promoter. This regio
n binds single-strand specific DNA binding proteins that are likely to
be important in con trolling transcription. (C) 1998 Academic Press.