Quantitative profiling of mRNA expression of glutathione S‐transferase superfamily genes in various tissues of bighead carp (Aristichthys nobilis)

Abstract

ABSTRACT:The expression of glutathione S-transferase (GST) is a crucial factor in determining the sensitivity of cells and organs in response to a variety of toxicants. In this study, we cloned the core nucleotide of alpha, kappa, mu, mGST, pi, rho, and theta-like GST genes from bighead carp (Aristichthys nobilis). Their derived amino acid sequences were clustered with other vertebrate GSTs in a phylogenetic tree, and the bighead carp GST sequences have the highest similarity with those from common carp and zebrafish. We quantified the constitutive mRNA transcription of GST isoforms in eight different tissues (liver, kidney, spleen, intestine, muscle, heart, brain, and gill). The information obtained from the present study could be distilled into a few generalized principles: multiple GST isoenzymes were ubiquitously expressed in all tissues; majority of GSTs had high constitutive expression in intestine, liver, and kidney. These findings are in agreement with the roles of these tissues in xenobiotic metabolism. At the same time, some unique findings were detected in the current experiment: (1) higher expression of most GSTs was observed in spleen; (2) the expression of GST pi was highest in almost all the studied tissues except muscle; the other two isoforms, GST alpha and rho, were also highly expressed in liver, kidney, intestine, spleen, heart, and brain of bighead carp. All these results strongly imply an important role of these GST isoforms in detoxification of ingested xenobiotics. C

Moringa Oleifera Leaf Extract Repairs the Oxidative Misbalance following Sub-Chronic Exposure to Sodium Fluoride in Nile Tilapia Oreochromis niloticus

“…Interestingly, the molecular expression of GST may be considered as a biomarker for xenobiotics exposure [72][73][74]. Many toxicologists expect that the highest level of GST expression may occur in the liver where metabolism mostly occurs [75]. In this study, the mRNA expression of GST in the liver of NaF-exposed fish showed a significant reduction compared to control fish.…”

Effects of malachite green on the mRNA expression of detoxification‐related genes in Nile tilapia (Oreochromis niloticus) and other major Chinese freshwater fishes

“…Our results also showed varied trends of the same gene in different fish. The possible explanations for the observed variations could be attributed to (1) the vulnerability to MG among different fish species was quite different (Steffens et al,1961; Alderman and Clifton‐Hadley,1993); and (2) that the constitutive mRNA expression of the same detoxification‐related was diverse in different fish species (Li et al,2010) which leads to the different detoxified ability. In this study, the constitutive mRNA expression level of CYP1A, GSTR, GSTA, GPX, UCP2, or HSP70 genes in the liver of Nile tilapia and other major Chinese freshwater fishes have been analyzed by semiquantitative PCR after MG exposure.…”

Identification and characterization of the zebrafish glutathione S‐transferase Pi‐1

“…Sequence analysis revealed that these two zebrafish GSTs contain sequences corresponding to the glutathione‐binding site (G‐site) and substrate‐binding site (H‐site) that are involved in the glutathione conjugation reaction . In fish such as zebrafish and bighead carp, GST Pi‐1 (GSTP1) is highly expressed in the liver, kidney, gills, and intestine, implying a role of this enzyme in detoxification . In humans, in addition to its role in detoxification, genetic polymorphisms of GSTP1 have been linked to prostate, testicular, and bladder cancer .…”

“…[26,30,31] In fish such as zebrafish and bighead carp, GST Pi-1 (GSTP1) is highly expressed in the liver, kidney, gills, and intestine, implying a role of this enzyme in detoxification. [12,32] In humans, in addition to its role in detoxification,…”