STRUCTURE OF THE GUINEA-PIG NEUTROPHIL CATIONIC PEPTIDE GENE

Guinea pig neutrophils contain the antimicrobial cationic peptides GNCP-1 and GNCP-2 in the granules. In this study, the GNCP gene was isolated, and the structure was characterized. Using cDNA probes, one phage clone was isolated from a guinea pig genomic library. The gene spanned > 3 kb, and comprised three exons and two introns. Sequence analysis revealed that the gene encoded GNCP-2. Exon 1 mainly coded for the 5' untranslated region, exon 2 coded for the prepro-peptide region of GNCP-2, and exon 3 coded for the mature peptide region of GNCP-2 and the 3' untranslated region. Primer extension analysis indicated that the transcription initiation site was located to a thymidine residue, 93 bp upstream of the ATG initiation codon of GNCP-2 mRNA. A possible TATA box was located 24 bp upstream of the transcription start site. Interestingly, the pyrimidine-rich sequences identified in the promoter regions of the human neutrophil elastase and myeloperoxidase genes were also found in the 5' flanking region of the GNCP-2 gene.