Genomic structure of NKG5, a human NK and T cell-specific activation gene

Abstract

We reported previously the isolation of a cDNA clone, designated NKG5, encoding a secreted protein that is expressed only in natural killer and T cells and is strongly upregulated upon cell activation. In this report we have isolated the NKG5 gene from a human placental genomic library and sequenced the gene and two kilobases of 5'-flanking DNA. Comparison with the cDNA sequence reveals that the NKG5 gene consists of five exons and four introns. Intron 1 contains a DNA segment that was reported to occur as an exon in 519, a closely related cDNA clone that was isolated from a T-cell library. This result indicates that NKG5 and 519 are alternative splicing products of a single gene. The 5'-flanking region of the NKG5 gene was analyzed for homology with the promoter regions of cytokines and other activation-induced genes showing lymphocyte-specific expression. Several segments displaying sequence similarity were identified. We also identified numerous sequence elements that have strong similarity to known binding sites for transcriptional regulatory proteins including T cell-specific and activation-specific regulatory factors. These findings are consistent with the cell-specific expression and the tight regulatory control that is observed for the NKG5 gene.

Characterization of a NK-lysin antimicrobial peptide gene from channel catfish

“…The five exons/four introns structural feature is conserved between the catfish NK-lysin gene and the NKG5 splicing variant of human granulysin (Fig. 3) [36].…”

NK-lysin of channel catfish: Gene triplication, sequence variation, and expression analysis

“…6). Only a few NK-lysin genes have been reported, but the five exons/four introns structural feature is conserved between the catfish gene and the human gene (Houchins et al, 1993). However, in humans, alternative splicing of granulysin gene led to the identification of two isoforms of granulysin referred to as NKG5 and 519.…”

“…The NK-lysin gene was initially cloned and characterized from humans, but its significance was unrealized until its orthologue was identified from porcine natural killer cells and cytotoxic T lymphocytes as an antimicrobial peptide (Manning et al, 1992;Houchins et al, 1993;Andersson et al, 1995). In recent years, extensive research has been conducted for the analysis of structure and antimicrobial activities of NK-lysin (Stenger et al, 1998;Ernst et al, 2000;Gansert et al, 2003;Jacobs et al, 2003).…”

NK Cells Use Perforin Rather than Granulysin for Anticryptococcal Activity

“…Our previous observations, using Cryptococcus neoformans, which is one of the most common lifethreatening fungal infections in patients who have compromised cell-mediated immunity, including AIDS (10 -12), indicated that granulysin is required for the CD8 T lymphocyte-mediated direct antifungal activity (13). The granulysin (519) gene is also constitutively expressed in NK cells (14), and in fact was cloned as NKG5 (15,16), and NK cells constitutively express granulysin transcripts; consequently, we felt that granulysin was the likely mechanism for the NK cell-mediated antimicrobial activity.…”