Structural organization of the 5 '-end and chromosomal assignment of humanplacental leucine aminopeptidase insulin-regulated membrane aminopeptidasegene

Placental leucine aminopeptidase (P-LAP) which is identical with cystine am inopeptidase as oxytocinase was found to be a homologue of rat insulin-regu lated membrane aminopeptidase (IRAP) by cDNA cloning. In this study, we con firmed 5'-end cDNA sequence of P-LAP and isolated genomic clones containing the upstream region of human P-LAP gene. The transcription initiation site s determined by primer extension located 478 and 480 bp upstream of the ini tiation methionine codon, 38 bp downstream of TATA box-like motif. The 5'-f lanking region of human P-LAP gene contained DNA-binding motifs for several ubiquitous transcription factors such as SP1 and AP2. Chromosomal localiza tion by fluorescence in situ hybridization showed that the gene was assigne d to 5q14.2-q15 of the human chromosome. This study establishes the genetic basis for P-LAP gene research, thereby leading to better understanding of the molecular mechanism underlying the P-LAP gene. (C) 1999 Academic Press.