Glutaredoxin 1 from Evolutionary Ancient Hydra: Characteristics of the Enzyme and Its Possible Functions in Cell

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Nusrat Perween^1,2,a, Komal Pekhale^1,b, Gauri Haval^1,3,c, Ganesh S. Bose^4,d, Smriti P. K. Mittal^4,e, Surendra Ghaskadbi^5,f, and Saroj S. Ghaskadbi^1,g,g*

¹Department of Zoology, Savitribai Phule Pune University, Pune 411007, India

²Department of Zoology, M. C. E. Society’s Abeda Inamdar Senior College, Pune 411001, India

³Department of Zoology, Abasaheb Garware College, Pune 411004, India

⁴Department of Biotechnology, Savitribai Phule Pune University, Pune 411007, India

⁵Developmental Biology Group, Agharkar Research Institute, Pune 411004, India

^* To whom correspondence should be addressed.

Received October 23, 2022; Revised February 20, 2023; Accepted February 20, 2023

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Glutaredoxin (Grx) is an antioxidant redox protein that uses glutathione (GSH) as an electron donor. Grx plays a crucial role in various cellular processes, such as antioxidant defense, control of cellular redox state, redox control of transcription, reversible S-glutathionylation of specific proteins, apoptosis, cell differentiation, etc. In the current study, we have isolated and characterized dithiol glutaredoxin from Hydra vulgaris Ind-Pune (HvGrx1). Sequence analysis showed that HvGrx1 belongs to the Grx family with the classical Grx motif (CPYC). Phylogenetic analysis and homology modeling revealed that HvGrx1 is closely related to Grx2 from zebrafish. HvGrx1 gene was cloned and expressed in Escherichia coli cells; the purified protein had a molecular weight of 11.82 kDa. HvGrx1 efficiently reduced β-hydroxyethyl disulfide (HED) with the temperature optimum of 25°C and pH optimum 8.0. HvGrx1 was ubiquitously expressed in all body parts of Hydra. Expression of HvGrx1 mRNA and enzymatic activity of HvGrx1 were significantly upregulated post H₂O₂ treatment. When expressed in human cells, HvGrx1 protected the cells from oxidative stress and enhanced cell proliferation and migration. Although Hydra is a simple invertebrate, HvGrx1 is evolutionary closer to its homologs from higher vertebrates (similar to many other Hydra proteins).

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KEY WORDS: glutaredoxin, Hydra, redox

DOI: 10.1134/S0006297923050097

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