Dataset Information

Genomic organization, 5'-flanking region and chromosomal localization of the human glutathione transferase A4 gene.

ABSTRACT: We have isolated and characterized a human glutathione transferase A4 (hGSTA4) subunit gene from a yeast artificial chromosome containing several other glutathione transferase alpha genes and pseudogenes. The homodimeric protein hGSTA4-4, is involved in the detoxification of 4-hydroxynonenal and other reactive electrophiles produced by oxidative metabolism, and may have a significant role in protecting intracellular components from oxidative damage. The hGSTA4 gene spans nearly 18 kb, contains seven exons, maps onto chromosome 6p12, and lies in close proximity to the 7SK small nuclear RNA gene in a head-to-tail orientation. The intron/exon borders conform to the standard rules, an open reading frame is present beginning at position 154 in exon 2, and the stop codon is at position 822 in exon 7. The transcription initiation site has been determined by primer extension analysis and is located 135 bp upstream of intron 1. Isolation and sequencing of the hGSTA4 gene 5'-flanking region revealed it to be devoid of TATA or CCAAT boxes but it does contain an initiator element overlapping the transcription start site, a GC box and putative binding sites for transcription factors AP1, STAT, GATA1 and NF-kappaB. Reverse transcription-PCR analysis revealed that hGSTA4 mRNA was present in all the tissues tested, although in low amounts, suggesting that this subunit may be ubiquitously expressed.

SUBMITTER: Desmots F

PROVIDER: S-EPMC1219889 | biostudies-other | 1998 Dec

REPOSITORIES: biostudies-other

ACCESS DATA

Similar Datasets

Project description:We have isolated and characterized a cDNA and partial gene encoding a murine subfamily 1 Theta class glutathione transferase (GST). The cDNA derived from mouse GSTT1 has an open reading frame of 720 bp encoding a peptide of 240 amino acids with a calculated molecular mass of 27356 Da. The encoded protein shares only 51% deduced amino acid sequence identity with mouse GSTT2, but greater than 80% deduced amino acid sequence identity with rat GSTT1 and human GSTT1. Mouse GSTT1-1 was expressed in Escherichia coli as an N-terminal 6x histidine-tagged protein and purified using immobilized-metal affinity chromatography on nickel-agarose. The yield of the purified recombinant protein from E. coli cultures was approx. 14 mg/l. Recombinant mouse GSTT1-1 was catalytically active towards 1, 2-epoxy-3-(p-nitrophenoxy)propane, 4-nitrobenzyl chloride and dichloromethane. Low activity towards 1-menaphthyl sulphate and 1-chloro-2,4-dinitrobenzene was detected, whereas mouse GSTT1-1 was inactive towards ethacrynic acid. Recombinant mouse GSTT1-1 exhibited glutathione peroxidase activity towards cumene hydroperoxide and t-butyl hydroperoxide, but was inactive towards a range of secondary lipid-peroxidation products, such as the trans-alk-2-enals and trans,trans-alka-2,4-dienals. Mouse GSTT1 mRNA is most abundant in mouse liver and kidney, with some expression in intestinal mucosa. Mouse GSTT1 mRNA is induced in liver by phenobarbital, but not by butylated hydroxyanisole, beta-napthoflavone or isosafrole. The structure of mouse GSTT1 is conserved with that of the subfamily 2 Theta class GST genes mouse GSTT2 and rat GSTT2, comprising five exons interrupted by four introns. The mouse GSTT1 gene was found, by in situ hybridization, to be clustered with mouse GSTT2 on chromosome 10 at bands B5-C1. This region is syntenic with the location of the human Theta class GSTs clustered on chromosome 22q11.2. Similarity searches of a mouse-expressed sequence tag database suggest that there may be two additional members of the Theta class that share 70% and 88% protein sequence identity with mouse GSTT1, but less than 55% sequence identity with mouse GSTT2.

Dataset Information

Genomic organization, 5'-flanking region and chromosomal localization of the human glutathione transferase A4 gene.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets