Characterization of a novel Obg-like ATPase in the protozoan Trypanosoma cruzi

Gradia, Daniela Fiori; Rau, Karlan; Umaki, Adriana Castilhos Souza; Souza, Flávia Sá Pereira de; Probst, Christian M.; Correa, Alejandro; Holetz, Fabíola; Ávila, Andréa Rodrigues; Krieger, Marco Aurélio; Goldenberg, Samuel; Fragoso, Stênio Perdigão

doi:10.1016/j.ijpara.2008.05.019

Cited by 46 publications

(70 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In animals (human and protozoa), YchF homologs are primarily regarded as ATPases (4,5,15). However, a crystallographic study and subsequent binding assays suggested the presence of a GTP binding site in the H. influenza YchF homolog (6).…”

Section: Discussionmentioning

confidence: 99%

“…A unique subgroup within the Obg family, the YchF proteins, exhibit relaxed nucleotide-binding specificities (4)(5)(6). All G proteins contain a G domain (composed of the G1-G5 motifs) for GTP binding and hydrolysis (4).…”

mentioning

confidence: 99%

“…The G4 motif (canonical sequence: NKxD) confers the specificity for binding GTP (4). In YchFs, the noncanonical G4 sequence (NxxE) is correlated with the loss of nucleotide-binding specificities (4,5). In some cases, ATP is the preferred ligand (4,5).…”

mentioning

confidence: 99%

“…In YchFs, the noncanonical G4 sequence (NxxE) is correlated with the loss of nucleotide-binding specificities (4,5). In some cases, ATP is the preferred ligand (4,5). However, the physiological significance of the ancient and evolutionarily conserved YchF proteins having the relaxed binding specificities for both ATP and GTP is still unknown.…”

mentioning

confidence: 99%

See 3 more Smart Citations

ATP binding by the P-loop NTPase OsYchF1 (an unconventional G protein) contributes to biotic but not abiotic stress responses

Cheung

Miao

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

G proteins are involved in almost all aspects of the cellular regulatory pathways through their ability to bind and hydrolyze GTP. The YchF subfamily, interestingly, possesses the unique ability to bind both ATP and GTP, and is possibly an ancestral form of G proteins based on phylogenetic studies and is present in all kingdoms of life. However, the biological significance of such a relaxed ligand specificity has long eluded researchers. Here, we have elucidated the different conformational changes caused by the binding of a YchF homolog in rice (OsYchF1) to ATP versus GTP by X-ray crystallography. Furthermore, by comparing the 3D relationships of the ligand position and the various amino acid residues at the binding sites in the crystal structures of the apo-bound and ligand-bound versions, a mechanism for the protein's ability to bind both ligands is revealed. Mutation of the noncanonical G4 motif of the OsYchF1 to the canonical sequence for GTP specificity precludes the binding/hydrolysis of ATP and prevents OsYchF1 from functioning as a negative regulator of plant-defense responses, while retaining its ability to bind/hydrolyze GTP and its function as a negative regulator of abiotic stress responses, demonstrating the specific role of ATP-binding/hydrolysis in disease resistance. This discovery will have a significant impact on our understanding of the structure-function relationships of the YchF subfamily of G proteins in all kingdoms of life.G TP-binding proteins (G proteins) play important roles in diverse fundamental biological processes in living organisms, including signal transduction, cell division, development, intracellular transport, translation, and others (1, 2). The functions and working mechanisms of some ancestral G proteins, which are believed to play essential roles in cellular processes, are still unknown. One such group is the Obg family, which features an N-terminal glycine-rich sequence, followed by a G domain for nucleotide binding and a C-terminal TGS (ThrRS, GTPase, and SpoT) domain that has nucleic acid binding affinity (3).A unique subgroup within the Obg family, the YchF proteins, exhibit relaxed nucleotide-binding specificities (4-6). All G proteins contain a G domain (composed of the G1-G5 motifs) for GTP binding and hydrolysis (4). The G4 motif (canonical sequence: NKxD) confers the specificity for binding GTP (4). In YchFs, the noncanonical G4 sequence (NxxE) is correlated with the loss of nucleotide-binding specificities (4, 5). In some cases, ATP is the preferred ligand (4, 5). However, the physiological significance of the ancient and evolutionarily conserved YchF proteins having the relaxed binding specificities for both ATP and GTP is still unknown.Only a few reports touch on the biological functions of YchF proteins and most focus on human and microorganisms (7-9). The YchF proteins may play a role in iron utilization and regulation of the Ton system in Brucella melitensis (7), and in the growth of the procyclic forms of Trypanosoma cruzi (5). The human YchF homolog hOLA...

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

ATP binding by the P-loop NTPase OsYchF1 (an unconventional G protein) contributes to biotic but not abiotic stress responses

Cheung

Miao

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Many Obg-like G/ ATPases are involved in ribosome biogenesis and ribosome binding has been observed for Escherichia coli (6,49) and Trypanosoma cruzi (16) YchF. The exact impact of YchF on ribosome biogenesis or translation is unknown, but yeast Ola1 possibly influences translational fidelity (39).…”

Section: Innovationmentioning

confidence: 99%

Redox Activation of the Universally Conserved ATPase YchF by Thioredoxin 1

Hannemann

Suppanz

et al. 2016

Antioxidants & Redox Signaling

View full text Add to dashboard Cite

Aims: YchF/Ola1 are unconventional members of the universally conserved GTPase family because they preferentially hydrolyze ATP rather than GTP. These ATPases have been associated with various cellular processes and pathologies, including DNA repair, tumorigenesis, and apoptosis. In particular, a possible role in regulating the oxidative stress response has been suggested for both bacterial and human YchF/Ola1. In this study, we analyzed how YchF responds to oxidative stress and how it potentially regulates the antioxidant response. Results: Our data identify a redox-regulated monomer-dimer equilibrium of YchF as a key event in the functional cycle of YchF. Upon oxidative stress, the oxidation of a conserved and surface-exposed cysteine residue promotes YchF dimerization, which is accompanied by inhibition of the ATPase activity. No dimers were observed in a YchF mutant lacking this cysteine. In vitro, the YchF dimer is dissociated by thioredoxin 1 (TrxA) and this stimulates the ATPase activity. The physiological significance of the YchF-thioredoxin 1 interaction was demonstrated by in vivo cross-linking, which validated this interaction in living cells. This approach also revealed that both the ATPase domain and the helical domain of YchF are in contact with TrxA. Innovation: YchF/Ola1 are the first redox-regulated members of the universally conserved GTPase family and are inactivated by oxidation of a conserved cysteine residue within the nucleotide-binding motif. Conclusion: Our data provide novel insights into the regulation of the so far ill-defined YchF/Ola1 family of proteins and stipulate their role as negative regulators of the oxidative stress response. Antioxid. Redox Signal. 24, 141-156.

show abstract

Regulation of cell-matrix adhesion by OLA1, the Obg-like ATPase 1

Jeyabal

Rubio

Chen

et al. 2014

Biochemical and Biophysical Research Communications

View full text Add to dashboard Cite

Attachment of cells to the extracellular matrix induces clustering of membrane receptor integrins which in turn triggers the formation of focal adhesions (FAs). The adaptor/scaffold proteins in FAs provide linkage to actin cytoskeleton, whereas focal adhesion kinase (FAK) and other FA-associated kinases and phosphatases transduce integrin-mediated signaling cascades, promoting actin polymerization and progression of cell spreading. In this study, we explored the role of OLA1, a newly identified member of Obg-like ATPases, in regulating cell adhesion processes. We showed that in multiple human cell lines RNAi-mediated downregulation of OLA1 significantly accelerated cell adhesion and spreading, and conversely overexpression of OLA1 by gene transfection resulted in delayed cell adhesion and spreading. We further found that OLA1-deficient cells had elevated levels of FAK protein and decreased Ser3 phosphorylation of cofilin, an actin-binding protein and key regulator of actin filament dynamics, while OLA1-overexpressing cells exhibited the opposite molecular alterations in FAK and cofilin. These findings suggest that OLA1 plays an important negative role in cell adhesion and spreading, in part through the regulation of FAK expression and cofilin phosphorylation, and manipulation of OLA1 may lead to significant changes in cell adhesion and the associated phenotypes.

show abstract

Characterization of a novel Obg-like ATPase in the protozoan Trypanosoma cruzi

Cited by 46 publications

References 37 publications

ATP binding by the P-loop NTPase OsYchF1 (an unconventional G protein) contributes to biotic but not abiotic stress responses

ATP binding by the P-loop NTPase OsYchF1 (an unconventional G protein) contributes to biotic but not abiotic stress responses

Redox Activation of the Universally Conserved ATPase YchF by Thioredoxin 1

Regulation of cell-matrix adhesion by OLA1, the Obg-like ATPase 1

Contact Info

Product

Resources

About