Structure and expression of a human class pi glutathione S-transferase messenger RNA.
We have used a rat glutathione S-transferase P (GST-P) complementary DNA as a probe to screen a human placenta complementary DNA library constructed in the lambda gt11 vector. One of the positive clones contained the complete coding region (630 base pair) and the entire 3'-noncoding region (78 base pair) of the putative human glutathione S-transferase pi (GST-pi) subunit mRNA. From the nucleotide sequence we deduced the complete amino acid sequence of the GST-pi subunit. It contained 209 amino acids with the relative molecular mass of Mr 23,224. Comparison of the amino acid sequences between GST-pi and GST-P subunits suggests that they are the corresponding enzymes in these species. GST-pi and GST-P both consist of 209 amino acids and differ in only 30 amino acids (85.6% homology). The difference in amino acid composition can explain the large difference in isoelectric point between GST-pi subunit (pI 5.5) and GST-P subunit (pI 6.9). The expression of GST-pi mRNA in some normal and cancerous tissues, including some hepatoma cell lines, hepatoma, and colon carcinoma specimens was determined using complementary DNA as a probe. The results indicate that the mode of the expression of GST-pi in humans is different from that of GST-P in rats.
Kano
T
T
Department of Biochemistry, University of Tokyo Faculty of Medicine, Japan.
Sakai
M
M
Muramatsu
M
M
D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000032:analysis; D005260:Female; D005982:Glutathione Transferase / Q000032:analysis / Q000235:genetics*; D006801:Humans; D008099:Liver / Q000201:enzymology; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D009369:Neoplasms / Q000201:enzymology; D010920:Placenta / Q000201:enzymology; D012333:RNA, Messenger / Q000032:analysis*; D012737:Sex Factors
D012333:RNA, Messenger; D004247:DNA; D005982:Glutathione Transferase