Isolation and characterization of the promoter region of the chicken N-cadherin gene.

N-cadherin (CDH2) is a member of the cadherin family of Ca2(+)-dependent cell-cell adhesion molecules. To investigate mechanisms controlling CDH2 transcription, we isolated and analyzed a genomic DNA sequence containing 2.8 kb of 5' flanking region and the first two exons of chicken CDH2. Sequence analysis of the promoter region of CDH2 revealed no CCATT or TATA boxes, but showed a high overall GC content, high CpG dinucleotide content, and several consensus Sp1 and Ap2 binding sequences. When fused to the cat reporter gene in transient transfection experiments, the sequence from positions -3231 to -118 (relative to the translation start site) directed high-level expression in CDH2-expressing chicken primary retinal cells and mouse N2A cells, but was much less active in chicken embryonic fibroblast cells and mouse 3T3 cells which do not express CDH2. Similarly, this promoter fragment directed variable, but neuronal-specific, expression of reporter genes in adult transgenic mice, but failed to produce the correct pattern of expression in other tissues, implying that additional sequences further upstream and/or within introns of CDH2 may play important roles in the transcriptional control.