Format

Send to

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 1991 Jun 25;266(18):11999-2007.

Separate promoters control transcription of the human aminopeptidase N gene in myeloid and intestinal epithelial cells.

Author information

1
Department of Hematology-Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee.

Abstract

Aminopeptidase N is a membrane-bound metalloprotease expressed on the surface of normal and malignant human myeloid cells, fibroblasts, hepatocytes, and the epithelial cells that form brush borders of the small intestine and kidney. Northern blot analysis of RNA extracted from these tissues revealed two distinct aminopeptidase N transcripts: a 3.7-kilobase (kb) transcript expressed by normal monocytes, myeloid leukemia cells, and fibroblasts and a 3.4-kb transcript expressed by intestinal epithelium and kidney cells. In intestinal epithelial cells, transcripts originated 47 base pairs upstream from the initiation codon and 22 base pairs downstream from a TATA box. By contrast, the longer transcripts found in myeloid cells and fibroblasts originated from several sites clustered in an upstream exon located 8 kb from the exon containing the initiation codon. Functional promoter activity was demonstrated by fusing sequences approximately 1 kb upstream from each transcription origin to bacterial reporter genes and transfecting the resultant constructs into murine NIH-3T3 fibroblasts. A novel feature of this system is that regulatory elements of the epithelial cell promoter, including the TATA box and transcription origin, are included within the 5'-untranslated region of the longer myeloid cell transcript. Both aminopeptidase N transcripts encode the same polypeptide, indicating that the physically distinct promoters must have evolved to regulate expression of this cell-surface peptidase by cells of different tissues.

PMID:
1675638
[Indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Support Center