An ATP-responsive metabolic cassette comprised of inositol tris/tetrakisphosphate kinase 1 (ITPK1) and inositol pentakisphosphate 2-kinase (IPK1) buffers diphosphosphoinositol phosphate levels.
Hayley Whitfield,Gaye F. White,Colleen Sprigg,Andrew M. Riley,Barry V. L. Potter,Andrew M. Hemmings,Charles A. Brearley +6 more
TLDR
The findings and the methods described will enable a full appraisal of the role of diphosphoinositol phosphates in plants and particularly the relative contribution of reversible inositol phosphate hydroxykinase and inositl phosphate phosphokinase activities to plant physiology.Abstract:
Inositol polyphosphates are ubiquitous molecular signals in metazoans, as are their pyrophosphorylated derivatives that bear a so-called 'high-energy' phosphoanhydride bond. A structural rationale is provided for the ability of Arabidopsis inositol tris/tetrakisphosphate kinase 1 to discriminate between symmetric and enantiomeric substrates in the production of diverse symmetric and asymmetric myo-inositol phosphate and diphospho-myo-inositol phosphate (inositol pyrophosphate) products. Simple tools are applied to chromatographic resolution and detection of known and novel diphosphoinositol phosphates without resort to radiolabeling approaches. It is shown that inositol tris/tetrakisphosphate kinase 1 and inositol pentakisphosphate 2-kinase comprise a reversible metabolic cassette converting Ins(3,4,5,6)P4 into 5-InsP7 and back in a nucleotide-dependent manner. Thus, inositol tris/tetrakisphosphate kinase 1 is a nexus of bioenergetics status and inositol polyphosphate/diphosphoinositol phosphate metabolism. As such, it commands a role in plants that evolution has assigned to a different class of enzyme in mammalian cells. The findings and the methods described will enable a full appraisal of the role of diphosphoinositol phosphates in plants and particularly the relative contribution of reversible inositol phosphate hydroxykinase and inositol phosphate phosphokinase activities to plant physiology.read more
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Journal ArticleDOI
Analysis of inositol phosphate metabolism by capillary electrophoresis electrospray ionization mass spectrometry.
Danye Qiu,Miranda S. C. Wilson,Verena B. Eisenbeis,Robert K. Harmel,Esther Riemer,Thomas M. Haas,Christopher Wittwer,Nikolaus Jork,Chunfang Gu,Stephen B. Shears,Gabriel Schaaf,Bernd Kammerer,Dorothea Fiedler,Adolfo Saiardi,Henning J. Jessen +14 more
TL;DR: Capillary electrophoresis coupled to electrospray ionization mass spectrometry (ESI-MS) is implemented to analyze complex mixtures of InsPs and PP-InsPs with high sensitivity, providing evidence for the existence of unknown inositol synthesis pathways in mammals and highlighting the potential of this method to dissect inositl phosphate metabolism and signalling.
Journal ArticleDOI
Intracellular phosphate sensing and regulation of phosphate transport systems in plants
TL;DR: This review has integrated prior established knowledge of Pi and PP-InsP metabolism, intracellular Pi sensing, and transcriptional responses according to the dynamics of cellular Pi status in plants.
Journal ArticleDOI
ITPK1 is an InsP6/ADP phosphotransferase that controls phosphate signaling in Arabidopsis
Esther Riemer,Danye Qiu,Debabrata Laha,Debabrata Laha,Robert K. Harmel,Philipp Gaugler,Verena Gaugler,Michael Frei,Mohammad-Reza Hajirezaei,Nargis Parvin Laha,Lukas Krusenbaum,Robin Schneider,Adolfo Saiardi,Dorothea Fiedler,Henning J. Jessen,Gabriel Schaaf,Ricardo Fabiano Hettwer Giehl +16 more
TL;DR: In this article, the authors combined different methods to obtain a comprehensive picture of how inositol (pyro)phosphate metabolism is regulated by Pi and dependent on the inositolin phosphate kinase ITPK1.
Journal ArticleDOI
Inositol phosphate kinases in the eukaryote landscape.
TL;DR: In this article, an evolutionary approach to understand the development of the "inositol phosphate code" in eukaryotes was presented, which revealed the loss of either ITPK, or of PPIP5K proteins in several species.
Posted ContentDOI
Arabidopsis inositol polyphosphate kinases IPK1 and ITPK1 modulate crosstalks between SA-dependent immunity and phosphate-starvation responses
Hitika Gulabani,Krishnendu Goswami,Yashika Walia,Jewel Jameeta Noor,Kishor D. Ingole,Abhisha Roy,Debabrata Laha,Gabriel Schaaf,Saikat Bhattacharjee +8 more
TL;DR: It is demonstrated that SA is induced in phosphate-deprived plants, however its defense-promoting functions are likely diverted to PSR-supportive roles, and selective InsP-kinases are revealed as crosstalk mediators among diverse signaling networks programming stress-appropriate adaptations.
References
More filters
Journal ArticleDOI
Features and development of Coot.
TL;DR: Coot is a molecular-graphics program designed to assist in the building of protein and other macromolecular models and the current state of development and available features are presented.
Journal ArticleDOI
AutoDock Vina: Improving the speed and accuracy of docking with a new scoring function, efficient optimization, and multithreading
Oleg Trott,Arthur J. Olson +1 more
TL;DR: AutoDock Vina achieves an approximately two orders of magnitude speed‐up compared with the molecular docking software previously developed in the lab, while also significantly improving the accuracy of the binding mode predictions, judging by tests on the training set used in AutoDock 4 development.
Journal ArticleDOI
The Phyre2 web portal for protein modeling, prediction and analysis
Lawrence A. Kelley,Stefans Mezulis,Christopher M. Yates,Christopher M. Yates,Mark N. Wass,Mark N. Wass,Michael J.E. Sternberg +6 more
TL;DR: An updated protocol for Phyre2, which uses advanced remote homology detection methods to build 3D models, predict ligand binding sites and analyze the effect of amino acid variants for a user's protein sequence.
Journal ArticleDOI
The energy charge of the adenylate pool as a regulatory parameter. Interaction with feedback modifiers.
TL;DR: An electrostatic spray apparatus and method for spraying electrically conductive coating materials on a continuous basis from an electrically grounded bulk coating supply.
Journal ArticleDOI
A phospholipase C-dependent inositol polyphosphate kinase pathway required for efficient messenger RNA export.
TL;DR: A genetic screen was conducted with a yeast mutant deficient in a factor Gle1p, which associates with the nuclear pore complex, and the common downstream effects of mutations were deficiencies in IP6 synthesis and messenger RNA export, indicating a role for IP6 in GLE1 function and messengerRNA export.