Biology:Glutaredoxin
| Glutaredoxin | |||||||||
|---|---|---|---|---|---|---|---|---|---|
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| Identifiers | |||||||||
| Symbol | Glutaredoxin | ||||||||
| Pfam | PF00462 | ||||||||
| Pfam clan | CL0172 | ||||||||
| InterPro | IPR002109 | ||||||||
| PROSITE | PDOC00173 | ||||||||
| SCOP2 | 1kte / SCOPe / SUPFAM | ||||||||
| OPM superfamily | 131 | ||||||||
| OPM protein | 1z9h | ||||||||
| CDD | cd02066 | ||||||||
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Glutaredoxins[1][2][3] (also known as Thioltransferase) are small redox enzymes of approximately one hundred amino-acid residues that use glutathione as a cofactor. In humans this oxidation repair enzyme is also known to participate in many cellular functions, including redox signaling and regulation of glucose metabolism.[4][5] Glutaredoxins are oxidized by substrates, and reduced non-enzymatically by glutathione. In contrast to thioredoxins, which are reduced by thioredoxin reductase, no oxidoreductase exists that specifically reduces glutaredoxins. Instead, glutaredoxins are reduced by the oxidation of glutathione. Reduced glutathione is then regenerated by glutathione reductase. Together these components compose the glutathione system.[6]
Like thioredoxin, which functions in a similar way, glutaredoxin possesses an active centre disulfide bond.[7] It exists in either a reduced or an oxidized form where the two cysteine residues are linked in an intramolecular disulfide bond. Glutaredoxins function as electron carriers in the glutathione-dependent synthesis of deoxyribonucleotides by the enzyme ribonucleotide reductase.[6] Moreover, GRX act in antioxidant defense by reducing dehydroascorbate, peroxiredoxins, and methionine sulfoxide reductase. Beside their function in antioxidant defense, bacterial and plant GRX were shown to bind iron-sulfur clusters and to deliver the cluster to enzymes on demand.[8]
In viruses
Glutaredoxin has been sequenced in a variety of viruses. On the basis of extensive sequence similarity, it has been proposed[9] that Vaccinia virus protein O2L is, it seems, a glutaredoxin. Bacteriophage T4 thioredoxin seems to be evolution-related. In position 5 of the pattern T4, thioredoxin has Val instead of Pro.
In plants
Approximately 30 GRX isoforms are described in the model plant Arabidopsis thaliana and 48 in Oryza sativa L. According to their redox-active centre, they are subgrouped in six classes of the CSY[C/S]-, CGFS-, CC-type and 3 groups with additional domain of unknown function. The CC-type GRXs are only found in higher plants. In Arabidopsis GRXs are involved in flower development and Salicylic acid signalling.[8]
Subfamilies
Human proteins containing this domain
GLRX; GLRX2; GLRX3; GLRX5; PTGES2
References
- ↑ "Thioredoxin and related proteins in procaryotes". FEMS Microbiology Reviews 54 (4): 271–97. December 1988. doi:10.1111/j.1574-6968.1988.tb02747.x. PMID 3152490.
- ↑ "Thioredoxin and glutaredoxin: small multi-functional redox proteins with active-site disulphide bonds". Biochemical Society Transactions 16 (2): 95–6. April 1988. doi:10.1042/bst0160095. PMID 3286320.
- ↑ "Thioredoxin and glutaredoxin systems". The Journal of Biological Chemistry 264 (24): 13963–6. August 1989. doi:10.1016/S0021-9258(18)71625-6. PMID 2668278.
- ↑ "Effect of age on the thioltransferase (glutaredoxin) and thioredoxin systems in the human lens". Investigative Ophthalmology & Visual Science 51 (12): 6598–604. December 2010. doi:10.1167/iovs.10-5672. PMID 20610843.
- ↑ "Thioredoxins and glutaredoxins as facilitators of protein folding". Biochimica et Biophysica Acta (BBA) - Molecular Cell Research. Redox regulation of protein folding 1783 (4): 641–50. April 2008. doi:10.1016/j.bbamcr.2008.02.003. PMID 18331844.
- ↑ 6.0 6.1 "Glutaredoxins: glutathione-dependent redox enzymes with functions far beyond a simple thioredoxin backup system". Antioxidants & Redox Signaling 6 (1): 63–74. February 2004. doi:10.1089/152308604771978354. PMID 14713336.
- ↑ "The glutaredoxin -C-P-Y-C- motif: influence of peripheral residues". Structure 12 (2): 289–300. February 2004. doi:10.1016/j.str.2004.01.009. PMID 14962389.
- ↑ 8.0 8.1 "The role of glutathione in photosynthetic organisms: emerging functions for glutaredoxins and glutathionylation". Annual Review of Plant Biology 59: 143–66. 2008. doi:10.1146/annurev.arplant.59.032607.092811. PMID 18444899. https://hal.inrae.fr/hal-02660326/file/2008%20Rouhier%20Jacquot%20ARPB.pdf.
- ↑ "Vaccinia virus encodes a protein with similarity to glutaredoxins". Virology 181 (1): 378–81. March 1991. doi:10.1016/0042-6822(91)90508-9. PMID 1994586.
External links
- Enzyme database entry
- Glutaredoxins at the US National Library of Medicine Medical Subject Headings (MeSH)
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