Claudin-18, a novel downstream target gene for the T/EBP/NKX2.1 homeodomain transcription factor, encodes lung- and stomach-specific isoforms through alternative splicing.

ABSTRACT: T/EBP/NKX2.1, a member of the NKX family of homeodomain-containing transcription factors, regulates the expression of a number of genes in lung and thyroid. Here we describe the isolation and characterization of a novel target gene, termed claudin-18, that is down-regulated in the lungs of T/ebp/Nkx2.1-null mouse embryos. The gene product exhibits an amino acid sequence similar to those of the claudin multigene family of proteins that constitute tight junction strands in epithelial cells. The gene was localized by fluorescence in situ hybridization to mouse chromosome 9 at region 9E3-F1 and to human chromosome 3 at region 3q21-23. The claudin-18 gene has two promoters, each with its own unique exon 1 that is spliced to common exons 2 through 5. Alternative usage of these promoters leads to

SUBMITTER: Niimi T 

PROVIDER: S-EPMC99911 | biostudies-literature | 2001 Nov

REPOSITORIES: biostudies-literature