THE 5' FLANKING SEQUENCES OF THE MOUSE P-CADHERIN GENE - HOMOLOGIES TO 5' SEQUENCES OF THE E-CADHERIN GENE AND IDENTIFICATION OF A 1ST 215-BASE-PAIR INTRON

A genomic clone containing the 5′ region of the mouse P-cadherin gene has been isolated from Balb/c mice. A major feature of this genomic sequence is the presence of a first intron (II), 215 bp long, located 48 bp downstream of the translation start ATG codon. The presence of II has been detected both in Balb/c and C57BL/6 mouse strains, being located at the same position with respect to coding sequences as in the mouse E-cadherin and chicken L-CAM genes. The transcription initiation site of the mouse P-cadherin gene has been located at about 68 nt from the ATG start codon, giving an estimation for the size of the first exon of the mouse P-cadherin gene of 116 bp. The sequence of the 5′ upstream region of the P-cadherin gene presents structural similarities with the recently described 5′ region of the mouse E-cadherin gene: absence of a TATA box, presence of a CAAT box at -65, two putative AP2-binding motifs, at -101 and +31, and a GC-rich region containing a potential SP1-binding element at -88. However, no sequence homologous to the palindromic sequence, E-pal, found on the E-cadherin promoter has been found in the 5′ region of the P-cadherin gene. These results indicate that, in contrast to a previous report, the mouse E and P-cadherin genes exhibit a similar genomic organization both containing 15 introns and a similar size for the first two exons.