Characterization of glutathione S-transferase enzymes in Dictyostelium discoideum suggests a functional role for the GSTA2 isozyme in cell proliferation and development

In this report, we extend our previous characterization of Dictyostelium discoideum glutathione S-transferase (DdGST) enzymes that are expressed in the eukaryotic model organism. Transcript profiling of gstA1-gstA5 (alpha class) genes in vegetative, log phase cells identified gstA2 and gstA3 with highest expression (6–7.5-fold, respectively) when compared to other gstA transcripts. Marked reductions in all gstA transcripts occurred under starvation conditions, with gstA2 and gstA3 exhibiting the largest decreases (-96% and -86.6%, respectively). When compared to their pre-starvation levels, there was also a 60 percent reduction in total GST activity. Glutathione (GSH) pull-down assay and mass spectroscopy detected three isozymes (DdGSTA1, DdGSTA2 and DdGSTA3) that were predominantly expressed in vegetative cells. Biochemical and kinetic comparisons between rDdGSTA2 and rDdGSTA3 shows higher activity of rDdGSTA2 to the CDNB (1-chloro-2,4-dinitrobenzene) substrate. RNAi-mediated knockdown of endogenous DdGSTA2 caused a 60 percent reduction in proliferation, delayed development, and altered morphogenesis of fruiting bodies, whereas overexpression of rDdGSTA2 enzyme had no effect. These findings corroborate previous studies that implicate a role for phase II GST enzymes in cell proliferation, homeostasis, and development in eukaryotic cells.

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Glutathione S-transferase 4 is a putative DIF-binding protein that regulates the size of fruiting bodies in Dictyostelium discoideum

Biochemistry and Biophysics Reports ◽

10.1016/j.bbrep.2016.09.006 ◽

2016 ◽

Vol 8 ◽

pp. 219-226 ◽

Cited By ~ 2

Author(s):

Hidekazu Kuwayama ◽

Haruhisa Kikuchi ◽

Yoshiteru Oshima ◽

Yuzuru Kubohara

Keyword(s):

Dictyostelium Discoideum ◽

Binding Protein ◽

Fruiting Bodies ◽

Glutathione S Transferase

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Characterization of methylation of rat liver cytosolic glutathione S-transferases by using reverse-phase h.p.l.c. and chromatofocusing

Biochemical Journal ◽

10.1042/bj2700483 ◽

1990 ◽

Vol 270 (2) ◽

pp. 483-489 ◽

Cited By ~ 16

Author(s):

J A Johnson ◽

T L Neal ◽

J H Collins ◽

F L Siegel

Keyword(s):

Rat Liver ◽

Time Course ◽

Glutathione S Transferase ◽

Reverse Phase ◽

Cytosolic Glutathione ◽

Glutathione S Transferases ◽

Rat Liver Cytosol ◽

Gst Activity

Glutathione S-transferase (GST) subunits in rat liver cytosol were separated by reverse-phase h.p.l.c.; five major proteins were isolated and identified as subunits 1, 2, 3, 4 and 8. F.p.l.c. chromatofocusing resolved the affinity-purified GST pool into nine different isoenzymes. The five basic (Alpha class) dimeric peaks of GST activity were 1-1, 1-2a, 1-2b, 2-2a and 2-2b. Reverse-phase h.p.l.c. analysis revealed that subunit 8 was also present in the protein peaks designated 1-1, 1-2a and 1-2b. The four neutral (Mu class) isoenzymes were 3-3, 3-4, 3-6 and 4-4. The GST pool was methylated in vitro before reverse-phase h.p.l.c. or f.p.l.c. chromatofocusing. Chromatofocusing indicated that the Mu class isoforms (3-3, 3-4 and 4-4) were the primary GSTs methylated, and h.p.l.c. analysis confirmed that subunits 3 and 4 were the major methyl-accepting GST subunits. The addition of calmodulin stimulated the methylation in vitro of GST isoenzymes 3-3, 3-4 and 4-4 by 3.0-, 7.5- and 9.9-fold respectively. Reverse-phase h.p.l.c. also indicated that only the methylation of GST subunits 3 and 4 was stimulated by calmodulin. Basic GST isoenzymes were minimally methylated and the methylation was not enhanced by calmodulin. Investigation of the time course of methylation of GST subunits 3 and 4 indicated that at incubation times less than 4 h the methylation of both Mu class subunits was stimulated by calmodulin, and that under such conditions subunit 4 was the preferred substrate. In contrast, there was essentially no calmodulin-stimulated methylation at incubation times of 4 or 6 h, and the methylation of subunit 3 was predominant. Kinetic parameters at 2 h of incubation were determined in the presence and in the absence of calmodulin. The addition of calmodulin doubled the Vmax. for methylation of both subunits 3 and 4 and decreased the Km of subunit 4 for S-adenosyl-L-methionine 3.6-fold. Finally, methylation was substoichiometric and after 6 h of incubation ranged from 2.8 to 7.6% on a mole-to-mole basis for subunits 4 and 3 respectively.

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Developmental Commitment in Dictyostelium discoideum

Eukaryotic Cell ◽

10.1128/ec.00223-07 ◽

2007 ◽

Vol 6 (11) ◽

pp. 2038-2045 ◽

Cited By ~ 18

Author(s):

Mariko Katoh ◽

Guokai Chen ◽

Emily Roberge ◽

Gad Shaulsky ◽

Adam Kuspa

Keyword(s):

Amino Acids ◽

Cell Proliferation ◽

Cyclic Amp ◽

Dictyostelium Discoideum ◽

Growth Phase ◽

Camp Signaling ◽

Phagocytic Function ◽

Fruiting Bodies ◽

Mutant Strains ◽

Multicellular Organisms

ABSTRACT Upon starvation, Dictyostelium discoideum cells halt cell proliferation, aggregate into multicellular organisms, form migrating slugs, and undergo morphogenesis into fruiting bodies while differentiating into dormant spores and dead stalk cells. At almost any developmental stage cells can be forced to dedifferentiate when they are dispersed and diluted into nutrient broth. However, migrating slugs can traverse lawns of bacteria for days without dedifferentiating, ignoring abundant nutrients and continuing development. We now show that developing Dictyostelium cells revert to the growth phase only when bacteria are supplied during the first 4 to 6 h of development but that after this time, cells continue to develop regardless of the presence of food. We postulate that the cells’ inability to revert to the growth phase after 6 h represents a commitment to development. We show that the onset of commitment correlates with the cells’ loss of phagocytic function. By examining mutant strains, we also show that commitment requires extracellular cyclic AMP (cAMP) signaling. Moreover, cAMP pulses are sufficient to induce both commitment and the loss of phagocytosis in starving cells, whereas starvation alone is insufficient. Finally, we show that the inhibition of development by food prior to commitment is independent of contact between the cells and the bacteria and that small soluble molecules, probably amino acids, inhibit development during the first few hours and subsequently the cells become unable to react to the molecules and commit to development. We propose that commitment serves as a checkpoint that ensures the completion of cooperative aggregation of developing Dictyostelium cells once it has begun, dampening the response to nutritional cues that might inappropriately block development.

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Characterization of liver injury, oval cell proliferation and cholangiocarcinogenesis in glutathione S-transferase A3 knockout mice

Carcinogenesis ◽

10.1093/carcin/bgx048 ◽

2017 ◽

Vol 38 (7) ◽

pp. 717-727 ◽

Cited By ~ 11

Author(s):

Dana R. Crawford ◽

Zoran Ilic ◽

Ian Guest ◽

Ginger L. Milne ◽

John D. Hayes ◽

...

Keyword(s):

Cell Proliferation ◽

Liver Injury ◽

Knockout Mice ◽

Oval Cell ◽

Glutathione S Transferase

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Unusual Occurrence of Two Bona-Fide CCA-Adding Enzymes in Dictyostelium discoideum

International Journal of Molecular Sciences ◽

10.3390/ijms21155210 ◽

2020 ◽

Vol 21 (15) ◽

pp. 5210

Author(s):

Lieselotte Erber ◽

Anne Hoffmann ◽

Jörg Fallmann ◽

Monica Hagedorn ◽

Christian Hammann ◽

...

Keyword(s):

Dictyostelium Discoideum ◽

Developmental Stages ◽

Model Organism ◽

Similar Distribution ◽

Detailed Characterization ◽

Social Amoeba ◽

Genes Encoding ◽

Bona Fide ◽

Unusual Occurrence

Dictyostelium discoideum, the model organism for the evolutionary supergroup of Amoebozoa, is a social amoeba that, upon starvation, undergoes transition from a unicellular to a multicellular organism. In its genome, we identified two genes encoding for tRNA nucleotidyltransferases. Such pairs of tRNA nucleotidyltransferases usually represent collaborating partial activities catalyzing CC- and A-addition to the tRNA 3′-end, respectively. In D. discoideum, however, both enzymes exhibit identical activities, representing bona-fide CCA-adding enzymes. Detailed characterization of the corresponding activities revealed that both enzymes seem to be essential and are regulated inversely during different developmental stages of D. discoideum. Intriguingly, this is the first description of two functionally equivalent CCA-adding enzymes using the same set of tRNAs and showing a similar distribution within the cell. This situation seems to be a common feature in Dictyostelia, as other members of this phylum carry similar pairs of tRNA nucleotidyltransferase genes in their genome.

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Purification and Characterization of a Novel Serine Protease from the Fruiting Bodies of a Rare Edible Medicinal Mushroom, Lyophyllum shimeji (Agaricomycetes)

International Journal of Medicinal Mushrooms ◽

10.1615/intjmedmushrooms.v18.i6.90 ◽

2016 ◽

Vol 18 (6) ◽

pp. 547-554 ◽

Cited By ~ 1

Author(s):

Xueran Geng ◽

Rigen Te ◽

Guoting Tian ◽

Yongchang Zhao ◽

Liyan Zhao ◽

...

Keyword(s):

Serine Protease ◽

Medicinal Mushroom ◽

Fruiting Bodies ◽

Purification And Characterization ◽

Lyophyllum Shimeji

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Chemoprotective Effects of Propolis on Aflatoxin B1-Induced Hepatotoxicity in Rats: Oxidative Damage and Hepatotoxicity by Modulating TP53, Oxidative Stress

Current Proteomics ◽

10.2174/1570164617666190925121720 ◽

2020 ◽

Vol 17 (3) ◽

pp. 191-199

Author(s):

Seval Yilmaz ◽

Fatih Mehmet Kandemir ◽

Emre Kaya ◽

Mustafa Ozkaraca

Keyword(s):

Oxidative Stress ◽

Gene Expression ◽

Oxidative Damage ◽

Aflatoxin B1 ◽

Tp53 Gene ◽

Control Group ◽

Glutathione S Transferase ◽

Gene Expressions ◽

Cat Gene ◽

Gst Activity

Objective: This study aimed to detect hepatic oxidative damage caused by aflatoxin B1 (AFB1), as well as to examine how propolis protects against hepatotoxic effects of AFB1. Method: Rats were split into four groups as control group, AFB1 group, propolis group, AFB1+ propolis group. Results: There was significant increase in malondialdehyde (MDA) level and tumor suppressor protein (TP53) gene expression, Glutathione (GSH) level, Catalase (CAT) activity, CAT gene expression decreased in AFB1 group in blood. MDA level and Glutathione-S-Transferase (GST) activity, GST and TP53 gene expressions increased in AFB1 group, whereas GSH level and CAT activity alongside CAT gene expression decreased in liver. AFB1+propolis group showed significant decrease in MDA level, GST activity, TP53 and GST gene expressions, GSH level and CAT activity and CAT gene expression increased in liver compared to AFB1 group. Conclusion: These results suggest that propolis may potentially be natural agent that prevents AFB1- induced oxidative stress and hepatotoxicity.

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