» Articles » PMID: 23163895

The Pseudophosphatase MK-STYX Inhibits Stress Granule Assembly Independently of Ser149 Phosphorylation of G3BP-1

Overview
Journal FEBS J
Specialty Biochemistry
Date 2012 Nov 21
PMID 23163895
Citations 16
Authors
Affiliations
Soon will be listed here.
Abstract

The pseudophosphatase MK-STYX (mitogen-activated protein kinase phosphoserine/threonine/tyrosine-binding protein) has been implicated in the stress response pathway. The expression of MK-STYX inhibits the assembly of stress granules, which are cytoplasmic storage sites for mRNA that form as a protective mechanism against stressors such as heat shock, UV irradiation and hypoxia. Furthermore, MK-STYX interacts with a key component of stress granules: G3BP-1 (Ras-GTPase activating protein SH3 domain binding protein-1). Because G3BP-1 dephosphorylation at Ser149 induces stress granule assembly, we initially hypothesized that the inhibition of stress granules by MK-STYX was G3BP-1 phosphorylation-dependent. However, in the present study, using MK-STYX constructs and G3BP-1 phosphomimetic or nonphosphorylatable mutants, we show that MK-STYX inhibits stress granule formation independently of G3BP-1 phosphorylation at Ser149. The introduction of point mutations at the 'active site' of MK-STYX that convert serine and phenylalanine to histidine and cysteine, respectively, is sufficient to generate an active enzyme. In separate experiments, we show that this active mutant, MK-STYX(active), has opposite effects to wild-type MK-STYK. Not only does MK-STYX(active) induce stress granules, but also it has the capacity to dephosphorylate G3BP-1. Taken together, these results provide evidence that the pseudophosphatase MK-STYX plays a key role in the cellular response to stress.

Citing Articles

STYXL1 regulates CCT complex assembly and flagellar tubulin folding in sperm formation.

Chen Y, Luo M, Tu H, Qi Y, Guo Y, Zhang X Nat Commun. 2024; 15(1):44.

PMID: 38168070 PMC: 10761714. DOI: 10.1038/s41467-023-44337-1.


Understanding Pseudophosphatase Function Through Biochemical Interactions.

Hinton S Methods Mol Biol. 2023; 2743:21-41.

PMID: 38147206 DOI: 10.1007/978-1-0716-3569-8_2.


The DUSP domain of pseudophosphatase MK-STYX interacts with G3BP1 to decrease stress granules.

Smailys J, Jiang F, Prioleau T, Kelley K, Mitchell O, Nour S Arch Biochem Biophys. 2023; 744:109702.

PMID: 37516290 PMC: 10500436. DOI: 10.1016/j.abb.2023.109702.


SQSTM1/p62 and Hepatic Mallory-Denk Body Formation in Alcohol-Associated Liver Disease.

Qian H, Ding W Am J Pathol. 2023; 193(10):1415-1426.

PMID: 36906265 PMC: 10642158. DOI: 10.1016/j.ajpath.2023.02.015.


The progress of research into pseudophosphatases.

Liu D, Zhang Y, Fang H, Yuan J, Ji L Front Public Health. 2022; 10:965631.

PMID: 36106167 PMC: 9464862. DOI: 10.3389/fpubh.2022.965631.


References
1.
FISCHER E, Tonks N, Charbonneau H, Cicirelli M, Cool D, Diltz C . Protein tyrosine phosphatases: a novel family of enzymes involved in transmembrane signalling. Adv Second Messenger Phosphoprotein Res. 1990; 24:273-9. View

2.
Wishart M, Denu J, Williams J, Dixon J . A single mutation converts a novel phosphotyrosine binding domain into a dual-specificity phosphatase. J Biol Chem. 1995; 270(45):26782-5. DOI: 10.1074/jbc.270.45.26782. View

3.
Azzedine H, Bolino A, Taieb T, Birouk N, Di Duca M, Bouhouche A . Mutations in MTMR13, a new pseudophosphatase homologue of MTMR2 and Sbf1, in two families with an autosomal recessive demyelinating form of Charcot-Marie-Tooth disease associated with early-onset glaucoma. Am J Hum Genet. 2003; 72(5):1141-53. PMC: 1180267. DOI: 10.1086/375034. View

4.
Wehner K, Schutz S, Sarnow P . OGFOD1, a novel modulator of eukaryotic translation initiation factor 2alpha phosphorylation and the cellular response to stress. Mol Cell Biol. 2010; 30(8):2006-16. PMC: 2849474. DOI: 10.1128/MCB.01350-09. View

5.
Thomas M, Loschi M, Desbats M, Boccaccio G . RNA granules: the good, the bad and the ugly. Cell Signal. 2010; 23(2):324-34. PMC: 3001194. DOI: 10.1016/j.cellsig.2010.08.011. View