ZFIN ID: ZDB-PUB-061108-18
Identification and expression of a novel class of glutathione-S-transferase from amphioxus Branchiostoma belcheri with implications to the origin of vertebrate liver
Fan, C., Zhang, S., Liu, Z., Li, L., Luan, J., and Saren, G.
Date: 2007
Source: The international journal of biochemistry & cell biology   32(2): 450-461 (Journal)
Registered Authors: Li, Lei, Liu, Zhenhui
Keywords: Glutathione-S-transferases, Amphioxus, In situ hybridization, Immunohistochemistry, Hepatic caecum
MeSH Terms:
  • Amino Acid Sequence
  • Animals
  • Antibody Specificity
  • Chordata, Nonvertebrate/anatomy & histology
  • Chordata, Nonvertebrate/enzymology*
  • Chordata, Nonvertebrate/genetics*
  • DNA, Complementary
  • Gene Expression*
  • Glutathione Transferase/chemistry
  • Glutathione Transferase/genetics*
  • Glutathione Transferase/immunology
  • Liver/metabolism
  • Molecular Sequence Data
  • Organ Specificity
  • Phylogeny
  • Recombinant Proteins/chemistry
  • Recombinant Proteins/genetics
  • Recombinant Proteins/immunology
  • Sequence Alignment
  • Vertebrates/anatomy & histology
  • Vertebrates/metabolism
PubMed: 17084657 Full text @ Int. J. Biochem. Cell Biol.
ABSTRACT
Glutathione-S-transferases have been identified in all the living species examined so far, yet little is known to date about them in amphioxus, a model organism for insights into the origin and evolution of vertebrates. We have isolated a cDNA encoding an amphioxus (Branchiostoma belcheri) glutathione-S-transferase with a predicted molecular mass of approximately 26kDa, from the gut cDNA library. The glutathione-S-transferase had 43.7-51.8% identity to most glutathione-S-transferases identified from aquatic organisms including fish and green alga, but it was much less identical (<27%) to other cytosolic glutathione-S-transferase classes. The phylogenetic analysis revealed that the glutathione-S-transferase was grouped together with most piscine and algal glutathione-S-transferases, separating from other cytosolic glutathione-S-transferase classes. Moreover, the glutathione-S-transferase had an exon-intron organization typical of zebrafish putative GST, red sea bream GSTR1 and plaice GSTA1 genes. The recombinant glutathione-S-transferase has been successfully expressed and purified, which showed a relatively high catalytic activity (3.37+/-0.1unit/mg) toward 1-chloro-2, 4-dinitrobenzene and a moderate activity toward ethacrynic acid (0.41+/-0.01unit/mg), although it had no detectable activity toward 1, 2-dichloro-4-nitrobenzene, 4-hydroxynonenal, 4-nitrobenzyl chloride and cumene hydroperoxide. In addition, we have revealed a tissue-specific expression pattern of the glutathione-S-transferase gene in B. belcheri, with the most abundant expression in the hepatic caecum. All these indicate that the amphioxus glutathione-S-transferase belongs to a novel rho-class of glutathione-S-transferases with a tissue-specific expression pattern. The relation between the glutathione-S-transferase expression in amphioxus hepatic caecum and the origin of vertebrate liver is also discussed.
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