Structure of the bifunctional isocitrate dehydrogenase kinase/phosphatase

Zheng, Jimin; Jia, Zongchao

doi:10.1038/nature09088

Cited by 67 publications

(92 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, Ser51, the regulatory phosphorylation site in eukaryotic initiation factor 2α (eIF2α), is sequestered within an α-helix, but interaction with its kinase PKR promotes melting of the helix to allow access to the phosphoacceptor residue (35,36). Similarly, bifunctional isocitrate dehydrogenase kinase/phosphatases in bacteria appear to induce a conformational rearrangement in their substrates that liberates a phosphorylation site residue that is normally buried and thus inaccessible (37). In these cases, the presence of the phosphorylation site in a folded helix serves as a mechanism for achieving a high degree of specificity for a particular phosphorylating kinase.…”

Section: Discussionmentioning

confidence: 99%

Control of serotonin transporter phosphorylation by conformational state

Zhang

Turk

Rudnick

2016

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

View full text Add to dashboard Cite

Serotonin transporter (SERT) is responsible for reuptake and recycling of 5-hydroxytryptamine (5-HT; serotonin) after its exocytotic release during neurotransmission. Mutations in human SERT are associated with psychiatric disorders and autism. Some of these mutations affect the regulation of SERT activity by cGMPdependent phosphorylation. Here we provide direct evidence that this phosphorylation occurs at Thr276, predicted to lie near the cytoplasmic end of transmembrane helix 5 (TM5). Using membranes from HeLa cells expressing SERT and intact rat basophilic leukemia cells, we show that agents such as Na + and cocaine that stabilize outward-open conformations of SERT decreased phosphorylation and agents that stabilize inward-open conformations (e.g., 5-HT, ibogaine) increased phosphorylation. The opposing effects of the inhibitors cocaine and ibogaine were each reversed by an excess of the other inhibitor. Inhibition of phosphorylation by Na + and stimulation by ibogaine occurred at concentrations that induced outward opening and inward opening, respectively, as measured by the accessibility of cysteine residues in the extracellular and cytoplasmic permeation pathways, respectively. The results are consistent with a mechanism of SERT regulation that is activated by the transport of 5-HT, which increases the level of inward-open SERT and may lead to unwinding of the TM5 helix to allow phosphorylation.(1) reported a rare missense mutation in the coding region of serotonin transporter (SERT) in two unrelated families. Within these families, individuals with the mutation (Ile425Val, or I425V) were more strongly affected with several psychiatric disorders, including obsessive-compulsive disorder and autism spectrum disorders. Subsequently, additional families with this mutation and others in SERT have been identified (2-8).In transfected cells, the I425V mutation led to enhanced 5-HT transport relative to WT SERT (5, 9). The enhanced transport was similar to the up-regulation of 5-HT transport that had been observed in rat basophilic leukemia (RBL-2H3) cells on stimulation of adenosine A3 receptors with subsequent NO formation and cGMP production (10). Results with heterologously expressed SERT suggest that the I425V mutation interferes with this pathway either by directly increasing basal SERT phosphorylation or by inhibiting SERT dephosphorylation (11).Mutation of serine and threonine residues on the cytoplasmic surface of SERT led to the identification of Thr276 as a potential cGMP-dependent phosphorylation site (12). From homology models based on prokaryotic and eukaryotic homologs, this residue is located near the cytoplasmic end of transmembrane helix 5 (TM5), a location that agrees with cysteine scanning accessibility studies (13) that also have shown this position to be poorly accessible to aqueous reagents. The unlikely location of a phosphorylation site in a transmembrane helix, and the inaccessibility of this position, cast some doubt on the proposal that Thr276 is the site of cGMP-stimulated phosphorylat...

show abstract

Section: Discussionmentioning

confidence: 99%

Control of serotonin transporter phosphorylation by conformational state

Zhang

Turk

Rudnick

2016

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

View full text Add to dashboard Cite

show abstract

“…Eukaryotic glycogen phosphorylase was the first enzyme reported to undergo reversible phosphorylation-dephosphorylation (614,615). A bacterial example is isocitrate dehydrogenase, which is (de)phosphorylated by a bifunctional converter enzyme (616)(617)(618). Bicyclic and multicyclic cascades can be formed by concatenating monocycles.…”

Section: Signal Transduction Cascadesmentioning

confidence: 99%

Nitrogen Assimilation in Escherichia coli: Putting Molecular Data into a Systems Perspective

Heeswijk¹,

Westerhoff

Boogerd³

2013

Microbiol Mol Biol Rev

225

260

View full text Add to dashboard Cite

SUMMARY We present a comprehensive overview of the hierarchical network of intracellular processes revolving around central nitrogen metabolism in Escherichia coli . The hierarchy intertwines transport, metabolism, signaling leading to posttranslational modification, and transcription. The protein components of the network include an ammonium transporter (AmtB), a glutamine transporter (GlnHPQ), two ammonium assimilation pathways (glutamine synthetase [GS]-glutamate synthase [glutamine 2-oxoglutarate amidotransferase {GOGAT}] and glutamate dehydrogenase [GDH]), the two bifunctional enzymes adenylyl transferase/adenylyl-removing enzyme (ATase) and uridylyl transferase/uridylyl-removing enzyme (UTase), the two trimeric signal transduction proteins (GlnB and GlnK), the two-component regulatory system composed of the histidine protein kinase nitrogen regulator II (NRII) and the response nitrogen regulator I (NRI), three global transcriptional regulators called nitrogen assimilation control (Nac) protein, leucine-responsive regulatory protein (Lrp), and cyclic AMP (cAMP) receptor protein (Crp), the glutaminases, and the nitrogen-phosphotransferase system. First, the structural and molecular knowledge on these proteins is reviewed. Thereafter, the activities of the components as they engage together in transport, metabolism, signal transduction, and transcription and their regulation are discussed. Next, old and new molecular data and physiological data are put into a common perspective on integral cellular functioning, especially with the aim of resolving counterintuitive or paradoxical processes featured in nitrogen assimilation. Finally, we articulate what still remains to be discovered and what general lessons can be learned from the vast amounts of data that are available now.

show abstract

“…This cycle is largely regulated by the expression of isocitrate dehydrogenase (IDH) 1 . In bacteria, the activity of IDH is controlled through phosphorylation and dephosphorylation [2][3][4] . In Staphylococcus aureus, the expression of virulence factors, toxins and biofilm formation requires active functioning of TCA cycle and serine/threonine protein kinases (PknB) [5][6][7][8][9][10][11] .…”

Section: Introductionmentioning

confidence: 99%

Phosphorylation controls the functioning ofStaphylococcus aureusisocitrate dehydrogenase – favours biofilm formation

Prasad¹,

Vasu²,

Yeswanth³

et al. 2015

Journal of Enzyme Inhibition and Medicinal Chemistry

View full text Add to dashboard Cite

Isocitrate dehydrogenase (IDH) gene from Staphylococcus aureus ATCC12600 was cloned, sequenced and characterized (HM067707). PknB site was observed in the active site of IDH; thus, it was predicted as IDH may be regulated by phosphorylation. Therefore, in this study, PknB, alkaline phosphatase III (SAOV 2675) and IDH genes (JN695616, JN645811 and HM067707) of S. aureus ATCC12600 were over expressed from clones PV 1, UVPALP-3 and UVIDH 1. On passing the cytosloic fractions through nickel metal chelate column, pure enzymes were obtained. Phosphorylation of pure IDH by PknB resulted in the complete loss of activity and was restored upon dephosphorylation with SAOV 2675 which indicated that phosphorylation and dephosphorylation regulate IDH activity in S. aureus. Further, when S. aureus ATCC12600 was grown in BHI broth, decreased IDH activity and increased biofilm units were observed; therefore, this regulation of IDH alters redox status in this pathogen favouring biofilm formation.

show abstract

Structure of the bifunctional isocitrate dehydrogenase kinase/phosphatase

Cited by 67 publications

References 37 publications

Control of serotonin transporter phosphorylation by conformational state

Control of serotonin transporter phosphorylation by conformational state

Nitrogen Assimilation in Escherichia coli: Putting Molecular Data into a Systems Perspective

Phosphorylation controls the functioning ofStaphylococcus aureusisocitrate dehydrogenase – favours biofilm formation

Contact Info

Product

Resources

About