Structural analysis of esp-1 gene (PRSS 21).

The esp-1 gene is originally cloned from human eosinophils and encodes a membrane-type serine protease. This gene is ubiquitously expressed in various tissues but not kidney or muscle, and highly expressed in testis. Among granulocytes, this gene is expressed in eosinophils but not neutrophils, although both are derived from myeloid progenitors. In the present study, we have cloned the esp-1 genome using a BAC library, and determined exon-intron junctions: This gene spans approximately 4.6 kb, and consists of 6 exons and 5 introns. On radiation hybrid and FISH analyses, the esp-1 gene was mapped to 16p13.3. In addition, we have cloned a new splicing variant form of esp-1 from a HeLa cell cDNA library, which contains many esp-1 clones. Both RNase protection and primer extension analyses revealed the transcription initiation site of the esp-1 gene is located at nucleotide position -106, residue G. Dual-luciferase reporter analysis revealed a GC-rich region between nucleotide positions, -106 and -189 containing one AP-1/Sp-1 binding site is responsible for the minimum promoter activity in HeLa cells. Copyright 1999 Academic Press.