Histidine Kinases In Signal Transduction
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Histidine Kinases In Signal Transduction
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Author : Masayori Inouye
language : en
Publisher: Elsevier
Release Date : 2002-11-13
Histidine Kinases In Signal Transduction written by Masayori Inouye and has been published by Elsevier this book supported file pdf, txt, epub, kindle and other format this book has been release on 2002-11-13 with Science categories.
Living cells are constantly sensing environmental changes, and their abilities to sense these changes and adapt to them are essential for their survival. In bacteria, histidine kinases are the major sensors for these environmental stresses, enabling cells to adapt to new growth conditions. Written by leading experts in the field, this book provides an up-to-date and comprehensive review on the structure and function of histidine kinases. It also provides extensive information on the physiological roles of histidine kinases in bacteria and eukaryotes. An an essential reference for cell biologists, microbiologists, molecular biologists, and biochemists interested in signal transduction. Experimental biologists and pharmacologists studying signal transduction systems in living organisms will also find it a valuable research tool. The first comprehensive book on the roles of histidine kinases in cells 23 in-depth chapters written by leading experts in the field Describes the most recent advances in the field of signal transduction
Role Of Signal Transduction Domains In Histidine Kinase Evolution And Activity
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Author : Bruk Mensa
language : en
Publisher:
Release Date : 2021
Role Of Signal Transduction Domains In Histidine Kinase Evolution And Activity written by Bruk Mensa and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2021 with categories.
The process by which various upstream sensor and signal-transduction domains of bacterial histidine kinases (HKs) modulate the activity of the conserved autokinase domain remains poorly understood. Specifically, why do most HKs contain modularly inserted signal transduction domains? How do HKs robustly evolve and finetune the coupling between stimulus sensor domains and the conserved autokinase domain, which are often separated by 10s of nanometers? What is the role of these intervening domains in fine-tuning signaling parameters such as the minimum/maximum responsiveness, mid-point, and steepness of signal transition of an HK? In this work, we examine signal transduction through model E. coli HKs, PhoQ and CpxA, which contain one of the most abundant signal transduction domains in HKs, the HAMP domain. We first generate a large set of single-point mutants of PhoQ, and simultaneously measure the signaling state of the ligand-binding sensor and the kinase activity of the autokinase in vitro, at several inducing ligand concentrations to assess the coupling between these two domains. We demonstrate that point mutants in the HAMP signal transduction domain significantly modulate the coupled behavior of the sensor and autokinase, producing markedly varied ligand-dependent responses. We further use the insertion of poly-glycine motifs (Gly7) to decouple domains from one another and qualitatively show that, intrinsically, the sensor domain has a drastically poor ligand-dependent state transition propensity, and similarly, the autokinase domain has a drastically high basal kinase activity. The HAMP domain strongly couples to both domains and is sufficient to adjust these propensities to what is observed in the full length PhoQ. We suggest that signal transduction in PhoQ occurs by an allosteric coupling mechanism, in which the HAMP domain strongly couples to and acts in opposition the underlying signaling state equilibria of PhoQ such that it is maximally responsive to physiologically relevant ranges of stimuli. We demonstrate the same phenomenon in two other E. coli HAMP containing HKs, CpxA and BaeS, and suggest this may be a common theme in the evolution of signal transduction domains in HKs. In order to quantitatively examine the feasibility of modulating various ligand-dependent properties that inform HK function through evolution, we next establish and experimentally fit a three-domain, two-state equilibrium allosteric signaling model. We demonstrate that small changes to the HAMP domain sequence allow for robust modulation of the signaling ensemble and provide quantitative measures for the strong modulation of both sensor and autokinase domains by the HAMP, as well as the effects of point-mutations and Gly7 insertions.We more fully examine the ability of the HAMP to couple strongly and influence the sensor and autokinase domains of PhoQ by introducing a large library of variants in the HAMP four-helix bundle hydrophobic core, as well as the junction between the HAMP and autokinase domains (the S-Helix) and selecting for variants with high PhoQ activity. We find that destabilizing the HAMP four-helix bundle hydrophobic core does indeed lead to higher kinase activity. Furthermore, we find that the wild-type S-Helix sequence is enriched in the high-activity population, along with sequences with comparable polarity or poor helical propensity. Taken together, these observations lend credence to the hypothesis that the thermodynamically preferred signaling state of the HAMP behaves as a negative allosteric regulator of the autokinase, and that this regulation is alleviated by destabilizing the core helical bundle structure as well as the alpha-helical motif that connects it to the autokinase. We investigate this relationship further using a deep learning method to establish sequence-activity predictive relationships and extract structural features that are essential for this behavior. Finally, we examine the question of whether the HAMP domain exists in two distinct structural states, or rather conformational ensembles that can be classified into one of two functional states. We examine signaling through the HAMP domain of an E. coli histidine kinase, CpxA, by constructing a small library of structurally diverse inputs into the HAMP domain and evaluate the resulting autokinase activity as a function of several S-helix point mutations. This analysis allows us to discern the relationship between different signal inputs into the HAMP domain as the linkage to the output domain (autokinase) is varied. We find that the HAMP seems to have a multiconformational landscape that is not explained by 2 unique structural conformations.In this thesis, we show that the insertion of signal transduction domains in HKs can significantly alter both the intrinsic behaviors of sensor and autokinase domains, as well as the coupling between them. These properties can be well-described through a coupled two-state allosteric mechanism, and easily finetuned through simple mutations to the signal transduction domain and its linkage to adjacent domains to achieve the desired physiologically relevant activity profile.
Predicting And Testing Determinants Of Histidine Kinase Functions By Leveraging Protein Sequence Information
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Author : Orr Ashenberg
language : en
Publisher:
Release Date : 2013
Predicting And Testing Determinants Of Histidine Kinase Functions By Leveraging Protein Sequence Information written by Orr Ashenberg and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013 with categories.
All cells sense and respond to their environments using signal transduction pathways. These pathways control a sweeping variety of cellular processes across the domains of life, but the pathways are often built from a small, shared set of protein domains. At the core of tens of thousands of signal transduction networks in bacteria is a pair of proteins, a histidine kinase and a response regulator. Upon receiving an input signal, a histidine kinase autophosphorylates and then catalyzes transfer of its phosphoryl group to a cognate response regulator, which often activates a transcriptional response. Bacteria typically encode dozens of kinases and regulators, and the kinases function as dimers in all known examples. This dimeric state raises two functional questions. Do histidine kinases specifically form dimers? Once a kinase has dimerized, does a chain in the dimer phosphorylate itself (cis) or its partner chain (trans)? Specific kinase dimerization is likely important to avoid detrimental crosstalk between separate signaling pathways, and how autophosphorylation occurs is central to kinase activity. In my thesis, I have taken biochemical and evolutionary approaches to identify molecular determinants for both dimerization specificity and autophosphorylation. To study dimerization specificity, I developed an in vitro binding assay to measure kinase dimerization, and I then showed that a paralogous pair of kinases from E. coli specifically formed homodimers over heterodimers. Residues important for dimerization specificity were predicted by measuring amino acid coevolution within kinases, which leverages the enormous amount of sequence information available for the kinase family. Experimental verification of these predictions showed that a set of residues at the base of the kinase dimerization domain was sufficient to establish homospecificity. This same region of the kinase, in particular the loops at the base of the kinase dimer, was also important for determining autophosphorylation mechanism. Recent work showed that kinases could autophosphorylate either in cis or in trans, and I found that a trans kinase could be made to autophosphorylate in cis by replacing its loop with the loop from a cis kinase. I also found that two sets of orthologs, despite having significantly diverged loop sequences, had conserved their autophosphorylation mechanisms. This raised the possibility that kinase loops may be under selection to maintain the same autophosphorylation mechanism.
Structural Studies On Transmembrane Signalling Mechanism Of Histidine Kinase Cita
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Author : Michele Salvi
language : en
Publisher:
Release Date : 2019
Structural Studies On Transmembrane Signalling Mechanism Of Histidine Kinase Cita written by Michele Salvi and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2019 with categories.
Perception of environmental changes and subsequent signal transduction are key aspects for the survival of an organism. In bacteria, two component systems (TCSs) consisting of a homodimeric receptor histidine kinase (HK) and a response regulator (RR) are the prevalent mechanism of stimulus sensing and cell signalling. They regulate motility, metabolism and development, and in addition, they are essential for virulence in a number of pathogenic species. The investigation of the signal transduction in TCSs is therefore essential to deepen our understanding of cell signalling and to develop a ...
Two Component Signaling Systems Part C
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Author :
language : en
Publisher: Academic Press
Release Date : 2010-03-01
Two Component Signaling Systems Part C written by and has been published by Academic Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2010-03-01 with Science categories.
Multicellular organisms must be able to adapt to cellular events to accommodate prevailing conditions. Sensory-response circuits operate by making use of a phosphorylation control mechanism known as the "two-component system." This volume, the third in a three-volume treatment edited by the same group of editors, includes a wide range of methods, including those dealing with the Sln-1 kinase pathway, triazole sensitivity in C. albicans, and histidine kinases in cyanobacteria circadian clock. Includes time-tested core methods and new innovations applicable to any researcher studing two-component signaling systems or histidine kinases Methods included are useful to both established researchers and newcomers to the field Relevant background and reference information given for procedures can be used as a guide to developing protocols in a number of disciplines
Histidine Phosphorylation
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Author : Claire E. Eyers
language : en
Publisher: Humana
Release Date : 2020-11-10
Histidine Phosphorylation written by Claire E. Eyers and has been published by Humana this book supported file pdf, txt, epub, kindle and other format this book has been release on 2020-11-10 with Science categories.
This volume details the current understanding of roles and regulation on histidine phosphorylation, describing methods for the characterization of protein phosphorylation on histidine. Chapters guide readers through in vitro systems, cell-based systems, comprehensive background review articles on histidine kinases and phosphatases. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Histidine Phosphorylation: Methods and Protocols aims to ensure successful results in the further study of this rapidly growing field.
Function Of Hybrid Histidine Kinases In Arabidopsis Flagellin Mediated Defence Responses
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Author : Yvonne Marion Stewart
language : en
Publisher:
Release Date : 2013
Function Of Hybrid Histidine Kinases In Arabidopsis Flagellin Mediated Defence Responses written by Yvonne Marion Stewart and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013 with categories.
In plants, the first line of microbial recognition relies on the perception of pathogen-associated molecular patterns (PAMPs) allowing plants to detect microorganisms and respond with a set of basal defence responses. The best studied PAMP is flagellin, the main protein component of bacterial flagella. The sensor histidine kinase AHK5 has been shown to play a novel role in mediating flagellin-induced stomatal closure. AHK5 belongs to a family of 9 Arabidopsis hybrid-histidine kinases (HKs). To further investigate the role of such HKs in flagellin-induced signal transduction, physiological responses to the flagellin derived peptide flg22 were examined in available hybrid HK mutant lines. Seedlings of the ethylene insensitive HK ETR1 mutant (etr1-1) showed dramatically reduced flg22 sensitivity as assayed by flg22-mediated seedling growth inhibition. A novel role for the hormone ethylene in flg22-mediated growth inhibition was thus identified. Conversely enhanced sensitivity to low concentrations of flg22 was observed in the AHK2 cytokinin receptor mutant (ahk2-2). However, the absence of flg22-associated growth phenotype in other cytokinin receptor mutants would suggest the role of AHK2 in flg22-mediated seedling growth inhibition may be independent of its role in cytokinin perception. Despite a wild-type sensitivity in aerial plant tissues, distinct flg22-mediated root growth arrest phenotypes were observed in plants defective in the HKs ETR1 and AHK5. Dissection of the mechanisms underlying flg22-mediated root growth inhibition led to the identification of nitric oxide and the ethylene precursor ACC as key secondary messengers. Further characterisation of etr1 mutants showed that, in addition to seedling growth inhibition, ethylene perception is also required for flg22-mediated callose deposition however surprisingly, does not appear to be a requirement for flg22-mediated bacterial immunity. Despite the known requirement for AHK5 in flg22-mediated stomatal closure, flg22-mediated post-invasive bacterial defences were found to be intact in ahk5-1 mutant plants. In summary this study has shown that ethylene perception via the ethylene receptor HK family plays an integral part in flg22-mediated signalling. In addition, organ/tissue specific functions for three of the nine hybrid kinases, AHK2, AHK5 and ETR1 in flg22-mediated signal transduction have been identified.
Transmembrane Signalling Structural And Functional Studies On Histidine Kinase Cita
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Author :
language : en
Publisher:
Release Date : 2015
Transmembrane Signalling Structural And Functional Studies On Histidine Kinase Cita written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2015 with categories.
Bacteria utilise two component systems (TCS) consisting of a homodimeric receptor histidine kinase (HK) and a response regulator (RR) as a prevalent mechanism of stimulus perception and signal transduction. TCSs are key players in the regulation of metabolism, motility and development, and in addition are crucial for virulence in a number of pathogenic species. The study of TCSs is therefore motivated by their importance as a fundamental and widely used signalling system. In this study, the Geobacillus thermodenitrificans Citrate receptor A (CitA) is used as a model system for HKs. Free cit...
Elucidating The Energetics Of Bacterial Signal Transduction
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Author : Kathleen S. Molnar
language : en
Publisher:
Release Date : 2015
Elucidating The Energetics Of Bacterial Signal Transduction written by Kathleen S. Molnar and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2015 with categories.
Bacteria transduce signals across the membrane using two-component systems, consisting of a membrane-spanning sensor histidine kinase and a cytoplasmic response regulator. The histidine kinase, PhoQ, serves as a master regulator of virulence response in S. typhimurium and E. coli. It also is inhibited by divalent cations, particularly Mg 2+. While the periplasmic sensor domain of this protein has a unique function, the cytoplasmic portion of this modular protein is made of structurally conserved domains found in many other bacterial sensor kinases. Signal transduction through these conserved domains is thought to be universal; however, the structural and energetic rearrangements that occur during signaling have generated numerous models. Through Bayesian inference we constructed a two-state model based on cysteine crosslinking data and homologous crystal structures. These two signaling states differ in membrane depth of the periplasmic acidic patch as well as the reciprocal displacement of diagonal helices along the dimer interface. Comparative studies of multiple histidine kinases suggest that diagonal displacement of helices is a common mode of signal transduction. A similar scissor-like model was previously ruled out in CheA-linked chemoreceptors; therefore, this new evidence suggests that sensor His-kinase and CheA-linked receptors possess different signaling mechanisms. To unify the various signaling mechanisms that exist for the different protein domains, we built a thermodynamic model based on Linked Equilibrating Domains (LED). We used this model to quantitatively interpret functional data of single-point Ala, Phe and Cys mutants throughout the signal transducing regions of PhoQ. Data from 35 mutants, including both activating and deactivating phenotypes, were globally fit using LED, and gross features such as V max and Kd were related to more nuanced population distributions and thermodynamic coupling. LED analysis highlights the principles by which individual signaling domains can be connected to create a functional signal transducer. These principles allow us to quantitatively explain signaling in histidine kinases and are likely to be broadly applicable to many other signal transduction proteins.
Protein Kinases And Stress Signaling In Plants
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Author : Girdhar K. Pandey
language : en
Publisher: John Wiley & Sons
Release Date : 2021-03-08
Protein Kinases And Stress Signaling In Plants written by Girdhar K. Pandey and has been published by John Wiley & Sons this book supported file pdf, txt, epub, kindle and other format this book has been release on 2021-03-08 with Science categories.
A comprehensive review of stress signaling in plants using genomics and functional genomic approaches Improving agricultural production and meeting the needs of a rapidly growing global population requires crop systems capable of overcoming environmental stresses. Understanding the role of different signaling components in plant stress regulation is vital to developing crops which can withstand abiotic and biotic stresses without loss of crop yield and productivity. Emphasizing genomics and functional genomic approaches, Protein Kinases and Stress Signaling in Plants is a comprehensive review of cutting-edge research on stress perception, signal transduction, and stress response generation. Detailed chapters cover a broad range of topics central to improving agricultural production developing crop systems capable of overcoming environmental stresses to meet the needs of a rapidly growing global population. This book describes the field of protein kinases and stress signaling with a special emphasis on functional genomics. It presents a highly valuable contribution in the field of stress perception, signal transduction and generation of responses against one or multiple stress signals. This timely resource: Summarizes the role of various kinases involved in stress management Enumerates the role of TOR, GSK3-like kinase, SnRK kinases in different physiological conditions Examines mitogen-activated protein kinases (MAPKs) in different stresses Describes the different aspects of calcium signaling under different stress conditions Examines photo-activated kinases (PAPKs) in varying light conditions Briefs the presence of tyrosine kinases in plants Highlights the cellular functions of receptor ]like protein kinases (RLKs) Possible implication of these kinases in developing stress tolerant crops Protein Kinases and Stress Signaling in Plants: Functional Genomic Perspective is an essential resource for researchers and students in the fields of plant molecular biology and signal transduction, plant responses to stress, plant cell signaling, plant protein kinases, plant biotechnology, transgenic plants and stress biology.