M. Buttiglione et al., CHARACTERIZATION OF THE 5' AND PROMOTER REGIONS OF THE GENE ENCODING THE MOUSE NEURONAL CELL-ADHESION MOLECULE F3, Molecular brain research, 29(2), 1995, pp. 297-309
F3 is a 135 kDa neuronal cell surface adhesive glycoprotein belonging
to the immunoglobulin supergene family (IgSF) which mediates heterophi
lic contact formation among neural cells and is involved in the contro
l of neurite growth. F3 expression is regulated, during critical devel
opmental periods, on neuronal subpopulations thus suggesting that cont
rol of F3 gene expression could be of morphogenetic relevance. To shed
light on the mechanism involved in the control of F3 gene expression
we isolated clones covering about 50 kilobases of the F3 gene which al
so included the promoter region. The study of F3 gene exon/intron orga
nization revealed that, like other neural IgSF molecules, each of the
first two F3 C2 domains is encoded by two exons while the N-terminus,
the signal peptide and the 5' untranslated region are each encoded by
distinct exons. A single transcription start site was identified, surr
ounded by a short 114 bp sequence able to direct reporter gene express
ion in both F3-expressing and -non-expressing cells. In addition, a ce
ll type-specific enhancer, only active in F3-expressing cells, was fou
nd immediately upstream to it. structural analysis of the promoter reg
ion revealed consensus sequences for binding transcription factors inv
olved in cell type-specific and/or developmental regulations. Most of
them are homeobox containing transcription factors thus suggesting tha
t regulation of F3 gene expression could be part of a large developmen
tal program.