Redox Regulation of the Human Dual Specificity Phosphatase YVH1 through Disulfide Bond Formation

YVH1 was one of the first eukaryotic dual specificity phosphatases cloned, and orthologues posses a unique C-terminal zinc-coordinating domain in addition to a cysteine-based phosphatase domain. Our recent results revealed that human YVH1 (hYVH1) protects cells from oxidative stress. This function requires phosphatase activity and the zinc binding domain. This current study provides evidence that the thiol-rich zinc-coordinating domain may act as a redox sensor to impede the active site cysteine from inactivating oxidation. Furthermore, using differential thiol labeling and mass spectrometry, it was determined that hYVH1 forms intramolecular disulfide bonds at the catalytic cleft as well as within the zinc binding domain to avoid irreversible inactivation during severe oxidative stress. Importantly, zinc ejection is readily reversible and required for hYVH1 activity upon returning to favorable conditions. This inimitable mechanism provides a means for hYVH1 to remain functionally responsive for protecting cells during oxidative stimuli. YVH1 was one of the first eukaryotic dual specificity phosphatases cloned, and orthologues posses a unique C-terminal zinc-coordinating domain in addition to a cysteine-based phosphatase domain. Our recent results revealed that human YVH1 (hYVH1) protects cells from oxidative stress. This function requires phosphatase activity and the zinc binding domain. This current study provides evidence that the thiol-rich zinc-coordinating domain may act as a redox sensor to impede the active site cysteine from inactivating oxidation. Furthermore, using differential thiol labeling and mass spectrometry, it was determined that hYVH1 forms intramolecular disulfide bonds at the catalytic cleft as well as within the zinc binding domain to avoid irreversible inactivation during severe oxidative stress. Importantly, zinc ejection is readily reversible and required for hYVH1 activity upon returning to favorable conditions. This inimitable mechanism provides a means for hYVH1 to remain functionally responsive for protecting cells during oxidative stimuli. Human YVH1 (hYVH1 2The abbreviations used are: hYVH1human YVH1DUSPdual specificity phosphatasePTPprotein-tyrosine phosphataseMALDImatrix-assisted laser desorption ionizationTOFtime of flightMSmass spectrometryMS/MStandem mass spectrometryPSDpostsource decayCAMcarbamidomethylatedNEMN-ethylmaleimidylCAFchemically assisted fragmentationbis-Tris2-[bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)propane-1,3-diolDiFMUP6,8-difluoro-4-methylumbelliferyl phosphateVHRvaccinia H1-relatedDTTdithiothreitolDTNBdithionitrobenzoic acidPAR4-(2-pyridylazo)resorcinolPCMBparachloromercuribenzoic acidNBD-Cl7-chloro-4-nitrobenzo-2-oxa-1,3-diazole. ; also known as DUSP12) is a member of the dual specificity phosphatase (DUSP) subfamily of protein-tyrosine phosphatases (PTPs) (1Alonso A. Sasin J. Bottini N. Friedberg I. Friedberg I. Osterman A. Godzik A. Hunter T. Dixon J. Mustelin T. Cell. 2004; 117: 699-711Abstract Full Text Full Text PDF PubMed Scopus (1530) Google Scholar, 2Denu J.M. Stuckey J.A. Saper M.A. Dixon J.E. Cell. 1996; 87: 361-364Abstract Full Text Full Text PDF PubMed Scopus (306) Google Scholar). It is constructed of an N-terminal DUSP catalytic domain and a unique C-terminal zinc coordinating domain (3Muda M. Manning E.R. Orth K. Dixon J.E. J. Biol. Chem. 1999; 274: 23991-23995Abstract Full Text Full Text PDF PubMed Scopus (42) Google Scholar). Poor characterization and lack of mitogen-activated protein kinase targeting motifs further classify this enzyme as an atypical DUSP (1Alonso A. Sasin J. Bottini N. Friedberg I. Friedberg I. Osterman A. Godzik A. Hunter T. Dixon J. Mustelin T. Cell. 2004; 117: 699-711Abstract Full Text Full Text PDF PubMed Scopus (1530) Google Scholar). YVH1 orthologues exhibit high evolutionary conservation and similar domain organization (3Muda M. Manning E.R. Orth K. Dixon J.E. J. Biol. Chem. 1999; 274: 23991-23995Abstract Full Text Full Text PDF PubMed Scopus (42) Google Scholar). Deletion of the yvh1 gene in yeast disrupts normal growth processes (4Beeser A.E. Cooper T.G. J. Bacteriol. 2000; 182: 3517-3528Crossref PubMed Scopus (33) Google Scholar), whereas insertion and expression of the hyvh1 gene is capable of restoring a normal yeast growth phenotype (3Muda M. Manning E.R. Orth K. Dixon J.E. J. Biol. Chem. 1999; 274: 23991-23995Abstract Full Text Full Text PDF PubMed Scopus (42) Google Scholar). Amplification of the dusp12/hyvh1 gene has been reported in multiple sarcomas, implicating a role for hYVH1 in human disease (5Mendrzyk F. Korshunov A. Benner A. Toedt G. Pfister S. Radlwimmer B. Lichter P. Clin. Cancer Res. 2006; 12: 2070-2079Crossref PubMed Scopus (190) Google Scholar, 6Kresse S.H. Berner J.M. Meza-Zepeda L.A. Gregory S.G. Kuo W.L. Gray J.W. Forus A. Myklebost O. Mol. Cancer. 2005; 4: 39Crossref PubMed Scopus (24) Google Scholar, 7Das S.K. Chu W.S. Hale T.C. Wang X. Craig R.L. Wang H. Shuldiner A.R. Froguel P. Deloukas P. McCarthy M.I. Zeggini E. Hasstedt S.J. Elbein S.C. Diabetes. 2006; 55: 2631-2639Crossref PubMed Scopus (26) Google Scholar). human YVH1 dual specificity phosphatase protein-tyrosine phosphatase matrix-assisted laser desorption ionization time of flight mass spectrometry tandem mass spectrometry postsource decay carbamidomethylated N-ethylmaleimidyl chemically assisted fragmentation 2-[bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)propane-1,3-diol 6,8-difluoro-4-methylumbelliferyl phosphate vaccinia H1-related dithiothreitol dithionitrobenzoic acid 4-(2-pyridylazo)resorcinol parachloromercuribenzoic acid 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole. Recently, deletion studies from our laboratory have shown that the C-terminal zinc binding domain of hYVH1 is not essential for intrinsic phosphatase activity in vitro; however, it is required for interaction with the ATPase domain of heat shock protein 70 (8Sharda P.R. Bonham C.A. Mucaki E.J. Butt Z. Vacratsis P.O. Biochem. J. 2009; 2: 391-401Crossref Scopus (29) Google Scholar). Similarly, overexpression of wild type hYVH1 but not catalytically dead or zinc coordinating domain deletion mutants prevents cell death induced by Fas receptor activation, heat shock, and hydrogen peroxide (H2O2) (8Sharda P.R. Bonham C.A. Mucaki E.J. Butt Z. Vacratsis P.O. Biochem. J. 2009; 2: 391-401Crossref Scopus (29) Google Scholar). Despite these findings, current information on hYVH1 enzymatic and physiological functions remains limited. PTPs and DUSPs share similar active site architecture and catalytic mechanism, characterized by the conserved HCX5R(S/T) motif (9Zhang Z.Y. Wang Y. Dixon J.E. Proc. Natl. Acad. Sci. U.S.A. 1994; 91: 1624-1627Crossref PubMed Scopus (252) Google Scholar, 10Denu J.M. Dixon J.E. Proc. Natl. Acad. Sci. U.S.A. 1995; 92: 5910-5914Crossref PubMed Scopus (175) Google Scholar). The unique microenvironment within the HCX5R(S/T) motif reduces the pKa value of the active site cysteine, enhancing both nucleophilicity and oxidation susceptibility (11Grzyska P.K. Kim Y. Jackson M.D. Hengge A.C. Denu J.M. Biochemistry. 2004; 43: 8807-8814Crossref PubMed Scopus (10) Google Scholar, 12Denu J.M. Tanner K.G. Biochemistry. 1998; 37: 5633-5642Crossref PubMed Scopus (824) Google Scholar). Stimulated or constituent generation of ROS can result in oxidative second messenger signaling responses capable of transient and reversible post-translational inactivation of both PTPs and DUSPs through oxidation of the catalytic cysteine (13Meng T.C. Fukada T. Tonks N.K. Mol. Cell. 2002; 9: 387-399Abstract Full Text Full Text PDF PubMed Scopus (890) Google Scholar, 14Tonks N.K. Cell. 2005; 121: 667-670Abstract Full Text Full Text PDF PubMed Scopus (606) Google Scholar, 15Lou Y.W. Chen Y.Y. Hsu S.F. Chen R.K. Lee C.L. Khoo K.H. Tonks N.K. Meng T.C. FEBS J. 2008; 275: 69-88Crossref PubMed Scopus (93) Google Scholar). This oxidative susceptibility and modification varies among PTPs and DUSPs, a likely consequence of slight variations in active site conformations or mediated through unique regulatory domains (16Groen A. Lemeer S. van der Wijk T. Overvoorde J. Heck A.J. Ostman A. Barford D. Slijper M. den Hertog J. J. Biol. Chem. 2005; 280: 10298-10304Abstract Full Text Full Text PDF PubMed Scopus (111) Google Scholar, 17Ross S.H. Lindsay Y. Safrany S.T. Lorenzo O. Villa F. Toth R. Clague M.J. Downes C.P. Leslie N.R. Cell. Signal. 2007; 19: 1521-1530Crossref PubMed Scopus (89) Google Scholar, 18Weibrecht I. Böhmer S.A. Dagnell M. Kappert K. Ostman A. Böhmer F.D. Free Radic. Biol. Med. 2007; 43: 100-110Crossref PubMed Scopus (54) Google Scholar). Accumulating evidence suggests that redox-mediated oxidation of PTPs is a dynamic modification that can differentially regulate PTPs (13Meng T.C. Fukada T. Tonks N.K. Mol. Cell. 2002; 9: 387-399Abstract Full Text Full Text PDF PubMed Scopus (890) Google Scholar, 19Fox G.C. Shafiq M. Briggs D.C. Knowles P.P. Collister M. Didmon M.J. Makrantoni V. Dickinson R.J. Hanrahan S. Totty N. Stark M.J. Keyse S.M. McDonald N.Q. Nature. 2007; 447: 487-492Crossref PubMed Scopus (35) Google Scholar). Sulfenic acid, cyclic sulfenamide, and disulfide bond formation have all been shown to facilitate stable, reversible active site modifications among various PTPs and DUSPs (12Denu J.M. Tanner K.G. Biochemistry. 1998; 37: 5633-5642Crossref PubMed Scopus (824) Google Scholar, 14Tonks N.K. Cell. 2005; 121: 667-670Abstract Full Text Full Text PDF PubMed Scopus (606) Google Scholar, 20Chiarugi P. Fiaschi T. Taddei M.L. Talini D. Giannoni E. Raugei G. Ramponi G. J. Biol. Chem. 2001; 276: 33478-33487Abstract Full Text Full Text PDF PubMed Scopus (170) Google Scholar). Furthermore, evidence suggests that oxidation predominantly and rapidly targets the active site cysteine, whereas other cysteinyl residues remain in the reduced state (15Lou Y.W. Chen Y.Y. Hsu S.F. Chen R.K. Lee C.L. Khoo K.H. Tonks N.K. Meng T.C. FEBS J. 2008; 275: 69-88Crossref PubMed Scopus (93) Google Scholar, 20Chiarugi P. Fiaschi T. Taddei M.L. Talini D. Giannoni E. Raugei G. Ramponi G. J. Biol. Chem. 2001; 276: 33478-33487Abstract Full Text Full Text PDF PubMed Scopus (170) Google Scholar). This study investigated the relationship between the zinc-coordinating C-terminal domain and the catalytic domain of hYVH1 during oxidative conditions. We provide data suggesting that the zinc binding domain can serve as a reducing agent during oxidative stress to impede the oxidation of the active site cysteine. Increased exposure to oxidative conditions readily induces disulfide bond formation within the zinc-coordinating and catalytic domains, resulting in concomitant zinc ejection and enzymatic inactivation. Zinc ejection is readily reversible and required for hYVH1 activity upon returning to reducing conditions. Thus, we propose a mechanism for phosphatase active site protection through the intrinsic redox buffering capacity of this unique zinc binding domain. HeLa cells were maintained in Dulbecco's modified Eagle's medium supplemented with 10% (v/v) fetal bovine serum at 37 °C and 5% CO2. Transient transfection was carried out at 70% confluence using FuGENE 6 HD (Roche Applied Science) according to the manufacturer's protocol. For H2O2 treatments, HeLa cells were exposed to the indicated concentrations for 1 h at 37 °C. Cell viability was determined using a fluorescein isothiocyanate-conjugated annexin according to the manufacturer's and as (8Sharda P.R. Bonham C.A. Mucaki E.J. Butt Z. Vacratsis P.O. Biochem. J. 2009; 2: 391-401Crossref Scopus (29) Google Scholar). were also with and using cells were using the and cells were by a annexin The of cells in the as determined by was The data shown from expression of and protein were as (3Muda M. Manning E.R. Orth K. Dixon J.E. J. Biol. Chem. 1999; 274: 23991-23995Abstract Full Text Full Text PDF PubMed Scopus (42) Google Scholar, P.R. Bonham C.A. Mucaki E.J. Butt Z. Vacratsis P.O. Biochem. J. 2009; 2: 391-401Crossref Scopus (29) Google Scholar). of the C-terminal zinc-coordinating domain deletion was (8Sharda P.R. Bonham C.A. Mucaki E.J. Butt Z. Vacratsis P.O. Biochem. J. 2009; 2: 391-401Crossref Scopus (29) Google Scholar). were with of at °C on to the protein were and 1 using at °C. were through a to was determined bovine serum as the and were and at °C The of all in this study was as by activity was at °C using the 6,8-difluoro-4-methylumbelliferyl phosphate were using of by with time were with in similar to (12Denu J.M. Tanner K.G. Biochemistry. 1998; 37: 5633-5642Crossref PubMed Scopus (824) Google Scholar). were a and data were were as of activity of reduced hYVH1 in dithiothreitol activity were and for both reduced hYVH1 and a phosphatase activity of the vaccinia H1-related was similar conditions. Similarly, at time of were with for to by the addition of as to the of was using a modified dithionitrobenzoic acid similar to one P.R. F. M. R. J. Biol. Chem. 2007; Full Text Full Text PDF PubMed Scopus Google Scholar). were for with concentrations of H2O2 and for with of were with in for and at was Zinc was using a acid as M. J. S. J. H. Mol. Biol. 2007; PubMed Scopus Google Scholar). were at time and with in phosphate and at was The addition of in zinc and the was were as of zinc zinc differential thiol labeling similar to one M. J. S. J. H. Mol. Biol. 2007; PubMed Scopus Google was to thiol in to oxidation. hYVH1 and were with a of H2O2 for with 10% acid and with were in supplemented with for 1 h at °C. was and as were in in the or of for at by the addition of for 1 h at °C. were as in and with or (Roche Applied were at various time with acid, and at °C for further of disulfide bond a of hYVH1 was modified using the as the manufacturer's The resulting have a acid to all were with acid in on the mass and tandem mass spectrometry using postsource decay was on as (8Sharda P.R. Bonham C.A. Mucaki E.J. Butt Z. Vacratsis P.O. Biochem. J. 2009; 2: 391-401Crossref Scopus (29) Google and with in fragmentation using the on the were as and for with or a of thiol were as to and with or for and with and as Similarly, hYVH1 was as or with a of H2O2 for h to zinc with were in the or of a slight of for to facilitate reversible zinc with H2O2 were in of and in the or of a slight of were with and the at was oxidation state was using the as (12Denu J.M. Tanner K.G. Biochemistry. 1998; 37: 5633-5642Crossref PubMed Scopus (824) Google Scholar, Biochemistry. PubMed Scopus Google Scholar). hYVH1 was and as and with 1 for 1 were as and with a by the at Our that hYVH1 can cells from oxidative as heat shock, Fas receptor activation, and H2O2 (8Sharda P.R. Bonham C.A. Mucaki E.J. Butt Z. Vacratsis P.O. Biochem. J. 2009; 2: 391-401Crossref Scopus (29) Google Scholar). a catalytically or a zinc domain deletion to that the phosphatase activity and the zinc binding domain required for the cell function of the of the hYVH1 we HeLa cells to of hYVH1 were to H2O2 at and concentrations with and cell at hYVH1 to cells to results that hYVH1 can cells to a of oxidative may a mechanism in to the cell of It is that the susceptibility of PTPs and DUSPs to oxidative conditions predominantly through oxidation of the cysteine within the active site to pKa hYVH1 has a zinc binding domain zinc-coordinating we that this domain may the susceptibility of inactivation at the active site a the was with hYVH1 in the DUSP catalytic domain and has been shown to to inactivation through formation of a acid (12Denu J.M. Tanner K.G. Biochemistry. 1998; 37: 5633-5642Crossref PubMed Scopus (824) Google Scholar). oxidative wild type zinc domain deletion and were to H2O2 and for phosphatase activity the reducing the activity of was that of both hYVH1 and of the zinc coordinating domain not in activity with wild type reducing conditions exposure to H2O2 at a of rapidly and hYVH1 to the oxidative activity of and and The activity similar to that of suggesting that the to inactivation by hYVH1 is mediated by the zinc binding domain. The addition of in of phosphatase activity among all Furthermore, wild type hYVH1 similar an of H2O2 with and these results that the zinc binding domain provides hYVH1 the capacity to impede inactivation. The that the C-terminal zinc coordinating domain may in oxidative inactivation of the of oxidative conditions on zinc we a to zinc in to oxidative conditions. of H2O2 similar to zinc was readily from hYVH1 the of phosphatase activity to the of zinc ejection at concentrations of H2O2 and all thiol oxidation and zinc was determined to the results that zinc ejection and activity during of oxidative stress is to thiol oxidation within both the zinc binding and active site multiple residues zinc ejection is the also suggests that the zinc coordinating may the active site thiol oxidation a was The catalytically dead (hYVH1 was also to the oxidation state of the active site cysteine wild type hYVH1 and the and cysteine with of thiol of protein with H2O2 of multiple was within as with oxidation of the active site cysteine to a cyclic sulfenamide, or acid we an of between wild type hYVH1 and the evidence that upon wild type hYVH1 one thiol the suggesting that the active site cysteine may in intramolecular disulfide bond formation during oxidative stress The data that the active site of hYVH1 may capable of an intramolecular disulfide This a mechanism to avoid irreversible oxidation during oxidative stress. to further the thiol of both reduced and hYVH1 was using through the of differential thiol labeling of reduced and carbamidomethylated hYVH1 were and for hYVH1 the active site at with that of an N-terminal thiol at of were hYVH1 of both of these however, both the active site and thiol in reduced at and a at of is the of these suggesting formation of an intramolecular disulfide bond The was using labeling to facilitate of this intramolecular upon modified at both a mass of was for this was using of this and the formation of an intramolecular disulfide bond between the active site cysteine and the N-terminal cysteine was of hYVH1 carbamidomethylated hYVH1 mass the active site and N-terminal thiol at and carbamidomethylated hYVH1 mass the reduced active site and N-terminal thiol at and reduced or is a intramolecular disulfide at of these and of hYVH1 hYVH1 mass is the disulfide at of the at The to the and of active site disulfide bond Similarly, mass of reduced or hYVH1 were and for hYVH1 was to differential thiol as and mass of all were or were to of the C-terminal zinc binding domain and a of and is whereas formation of one at is suggesting that reduced during oxidation differentially hYVH1 in the of at and to the reduced and that in addition to the of the active site to an intramolecular disulfide the zinc-coordinating residues in the C-terminal domain in a disulfide both oxidation of the were not further formation of disulfide bonds within both bond formation within the zinc-coordinating domain this domain to zinc reducing conditions and disulfide bonds oxidative conditions in a reversible regulatory the C-terminal domain is capable of regulatory of zinc was with the or H2O2 results in zinc ejection in the of reducing This is readily and rapidly reversible to upon the addition of reducing upon returning to reducing zinc to a for catalytic zinc ejection and from the hYVH1 with of activity in with hYVH1 reducing conditions the C-terminal zinc domain deletion activity similar conditions. This suggests that the C-terminal zinc is required to the phosphatase domain. The results that oxidation of hYVH1 is a reversible reversible oxidation of can readily at thiol oxidation disulfide bonds and further disulfide bond formation upon oxidation of was used to for the of acid interaction with a the a of however, interaction with a acid results in formation of an a of for between these Biochemistry. PubMed Scopus Google Scholar). was used to evidence of acid formation was upon that disulfide bond formation is the oxidative modification of hYVH1 cysteine This current study has to our that hYVH1 as a cell phosphatase in to oxidative stress conditions. we have revealed that the zinc binding domain is for hYVH1 to oxidative inactivation of phosphatase other phosphatases have shown the to oxidation of active by various (16Groen A. Lemeer S. van der Wijk T. Overvoorde J. Heck A.J. Ostman A. Barford D. Slijper M. den Hertog J. J. Biol. Chem. 2005; 280: 10298-10304Abstract Full Text Full Text PDF PubMed Scopus (111) Google Scholar, 17Ross S.H. Lindsay Y. Safrany S.T. Lorenzo O. Villa F. Toth R. Clague M.J. Downes C.P. Leslie N.R. Cell. Signal. 2007; 19: 1521-1530Crossref PubMed Scopus (89) Google Scholar, 18Weibrecht I. Böhmer S.A. Dagnell M. Kappert K. Ostman A. Böhmer F.D. Free Radic. Biol. Med. 2007; 43: 100-110Crossref PubMed Scopus (54) Google Scholar, 20Chiarugi P. Fiaschi T. Taddei M.L. Talini D. Giannoni E. Raugei G. Ramponi G. J. Biol. Chem. 2001; 276: 33478-33487Abstract Full Text Full Text PDF PubMed Scopus (170) Google Scholar), this is the first to the of a dynamic zinc coordinating domain in oxidative for a The was to have activity hYVH1 the reducing conditions. in the of activity whereas hYVH1 maintained of activity of was readily reversible upon with is with multiple other studies of PTPs and DUSPs (11Grzyska P.K. Kim Y. Jackson M.D. Hengge A.C. Denu J.M. Biochemistry. 2004; 43: 8807-8814Crossref PubMed Scopus (10) Google Scholar, 12Denu J.M. Tanner K.G. Biochemistry. 1998; 37: 5633-5642Crossref PubMed Scopus (824) Google Scholar). This result the of as to redox conditions and suggests that hYVH1 may to activity during of oxidative stress other PTPs The of cells also this hYVH1 has intrinsic phosphatase activity in reducing conditions with is that it all of the residues known to for catalytic It may that hYVH1 is for physiological or that it is functionally in of to active stress conditions. We the of hYVH1 by to this and the relationship between the catalytic domain and the result was the that ejection of zinc in to high of H2O2 with a in phosphatase The zinc binding domain of hYVH1 zinc-coordinating with of the coordinating residues (3Muda M. Manning E.R. Orth K. Dixon J.E. J. Biol. Chem. 1999; 274: 23991-23995Abstract Full Text Full Text PDF PubMed Scopus (42) Google Scholar). residues that the zinc may act as a redox the active site This is by the zinc and activity shown in to a between of zinc ejection and of inactivation. of zinc is not and oxidation of multiple residues whereas enzymatic inactivation is to the active site cysteine Thus, this the that the zinc binding domain of hYVH1 may serve as a redox capable of protecting the active site to a through oxidation of zinc-coordinating the of active site we thiol in to The active site was used for The conditions the the residues that in wild type The hYVH1 was at the residues oxidative hYVH1 to the coordinating residues in the zinc binding domain. We were these conditions that wild type and the the of to oxidation of the active site we one thiol in the This result the that the active site cysteine in the formation of an intramolecular disulfide bond upon resulting in one thiol for the this an thiol remain for with to the thiol redox of the multiple cysteine residues in hYVH1 were using The active site and an N-terminal were by mass of carbamidomethylated hYVH1 both were however, the of reduced forms of with an at oxidation of these residues were and the of reduced forms the of oxidative conditions. the disulfide mass of these is to the oxidation. the of the the was to and evidence of an disulfide bond is a shown as in with by spectrometry of the C-terminal deletion also this intramolecular disulfide bond formation upon oxidation our studies that activity oxidative conditions as well as the formation of an intramolecular disulfide bond within the active the thiol of the C-terminal zinc-coordinating were by mass and reduced were as and in the mass all zinc thiol were however, a at a reduced thiol oxidation Furthermore, oxidation of these were not readily labeling in the of all in the mass at and may to of a and modified thiol at residues and and evidence was were the differential thiol We a disulfide bond the C-terminal thiol and these data further the that the C-terminal zinc-coordinating domain is capable of as a redox oxidation of thiol resulting in disulfide bond the of and reduced thiol oxidative conditions the that this can act as a reducing agent in of a catalytically active The capacity of hYVH1 to disulfide bonds the that enzymatic inactivation and zinc reversible with a of reducing hYVH1 was capable of of zinc the activity of hYVH1 in the of reducing in a in activity of hYVH1 whereas the C-terminal deletion was that both a reduced active site and zinc for activity in during reducing the of of zinc from oxidative conditions. This reversible capacity of zinc binding and disulfide bond formation suggests a dynamic regulatory mechanism conditions of oxidative stress The role of hYVH1 remains and has been for this the phosphatase activity of hYVH1 is required for function (8Sharda P.R. Bonham C.A. Mucaki E.J. Butt Z. Vacratsis P.O. Biochem. J. 2009; 2: 391-401Crossref Scopus (29) Google Scholar), of during oxidative stress conditions is for of hYVH1 can cells from various it has been that YVH1 is a in yeast Y. A. 2009; PubMed Scopus Google Scholar). hYVH1 a similar role in human it to the function of hYVH1 in this study the of during stress. spectrometry and studies to further the role of hYVH1 in the of this redox mechanism has the value of the zinc binding domain of This unique regulatory mechanism also further on the of cysteine-based phosphatases to with the of oxidative We for of the and for with

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.