Towards the Idea of Molecular Brains

International Journal of Molecular Sciences, Journal Year: 2021, Volume and Issue: 22(21), P. 11868 - 11868

Published: Nov. 1, 2021

How can single cells without nervous systems perform complex behaviours such as habituation, associative learning and decision making, which are considered the hallmark of animals with a brain? Are there molecular that underlie cognitive properties equivalent to those This review follows development idea brains from Darwin’s “root brain hypothesis”, through bacterial chemotaxis, recent discovery neuron-like r-protein networks in ribosome. By combining structural biology view Bayesian approach, this explores evolutionary labyrinth information processing across scales. Ribosomal protein open window into what were probably earliest signalling emerge before radiation three kingdoms. While ribosomal characterised by long-lasting interactions between their nodes, cell essentially based on transient interactions. As corollary, while signals propagated persistent may be ephemeral, whose constrain diffusing cytoplasm durable time, post-translational modifications proteins or second messenger synthesis. The duration nature signals, turn, implies different mechanisms for integration multiple making. Evolution then reinvented metazoans. simple display architectural functional analogies comparison could suggest scale invariance processing. At level, significant complexification eukaryotic is associated burst acquisition new conserved aromatic amino acids. Knowing residues play critical role allosteric receptors channels, observation suggests general π charged acids signal We think these findings provide basis designing future computers organic processors.

Language: Английский

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New Insight Into Phytochromes: Connecting Structure to Function

Annual Review of Plant Biology, Journal Year: 2024, Volume and Issue: 75(1), P. 153 - 183

Published: July 22, 2024

Red and far-red light–sensing phytochromes are widespread in nature, occurring plants, algae, fungi, prokaryotes. Despite at least a billion years of evolution, their photosensory modules remain structurally functionally similar. Conversely, nature has found remarkably different ways transmitting light signals from the photosensor to diverse physiological responses. We summarize key features phytochrome structure function discuss how these correlated, bilin environment affects chromophore induces cellular signals. Recent advances structural characterization bacterial plant have resulted paradigm changes research that we context present-day knowledge. Finally, highlight questions be answered suggest some benefits understanding function.

Language: Английский

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Signal transduction in photoreceptor histidine kinases

Protein Science, Journal Year: 2019, Volume and Issue: 28(11), P. 1923 - 1946

Published: Aug. 9, 2019

Abstract Two‐component systems (TCS) constitute the predominant means by which prokaryotes read out and adapt to their environment. Canonical TCSs comprise a sensor histidine kinase (SHK), usually transmembrane receptor, response regulator (RR). In signal‐dependent manner, SHK autophosphorylates in turn transfers phosphoryl group RR then elicits downstream responses, often form of altered gene expression. SHKs also catalyze hydrolysis phospho‐RR, hence, tightly adjusting overall degree phosphorylation. Photoreceptor kinases are subset mostly soluble, cytosolic that sense light near‐ultraviolet near‐infrared spectral range. Owing experimental tractability, photoreceptor serve as paradigms provide unusually detailed molecular insight into signal detection, decoding, regulation activity. The synthesis recent results on receptors with light‐oxygen‐voltage, bacteriophytochrome microbial rhodopsin units identifies recurring, joint signaling strategies. Light signals initially absorbed module converted subtle rearrangements α helices, through pivoting rotation. These conformational transitions propagate parallel coiled‐coil linkers effector unit changes left‐handed superhelical winding. Within effector, conformations triggered modulate solvent accessibility residues engaged phosphatase activities. Taken together, consistent view entire trajectory from detection output emerges. underlying allosteric mechanisms could widely apply TCS general.

Language: Английский

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PAS domains in bacterial signal transduction

Current Opinion in Microbiology, Journal Year: 2021, Volume and Issue: 61, P. 8 - 15

Published: Feb. 26, 2021

Language: Английский

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Signal transduction in light-oxygen-voltage receptors lacking the active-site glutamine

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: May 12, 2022

Abstract In nature as in biotechnology, light-oxygen-voltage photoreceptors perceive blue light to elicit spatiotemporally defined cellular responses. Photon absorption drives thioadduct formation between a conserved cysteine and the flavin chromophore. An equally conserved, proximal glutamine processes resultant protonation into downstream hydrogen-bond rearrangements. Here, we report that this glutamine, long deemed essential, is generally dispensable. its absence, several receptors invariably retained productive, if often attenuated, signaling Structures of paradigm at around 1 Å resolution revealed highly similar light-induced conformational changes, irrespective whether present. Naturally occurring, glutamine-deficient likely serve bona fide photoreceptors, showcase for diguanylate cyclase. We propose without water molecules transiently approach chromophore thus propagate downstream. Signaling appears intrinsic receptors, which pertains biotechnological applications suggests evolutionary descendance from redox-active flavoproteins.

Language: Английский

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Leveraging the histidine kinase-phosphatase duality to sculpt two-component signaling

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: June 10, 2024

Language: Английский

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Tips and turns of bacteriophytochrome photoactivation

Photochemical & Photobiological Sciences, Journal Year: 2020, Volume and Issue: 19(11), P. 1488 - 1510

Published: Oct. 27, 2020

Phytochromes are ubiquitous photosensor proteins, which control the growth, reproduction and movement in plants, fungi bacteria. switch between two photophysical states depending on light conditions. In analogy to molecular machines, absorption induces a series of structural changes that transduced from bilin chromophore, through protein, output domains. Recent progress towards understanding this mechanism signal transduction has been manifold. We describe with focus bacteriophytochromes. along three tiers, chromophore-binding pocket, photosensory module, discuss possible interconnections tiers conclude by presenting future directions open questions. hope review may serve as compendium guide spectroscopic studies designed understand signaling phytochromes.

Language: Английский

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A light life together: photosensing in the plant microbiota

Photochemical & Photobiological Sciences, Journal Year: 2021, Volume and Issue: 20(3), P. 451 - 473

Published: March 1, 2021

Bacteria and fungi of the plant microbiota can be phytopathogens, parasites or symbionts that establish mutually advantageous relationships with plants. They are often rich in photoreceptors for UVA-Visible light, many cases, they exhibit light regulation growth patterns, infectivity virulence, reproductive traits, production pigments metabolites. In addition to light-driven effects, demonstrated via generation photoreceptor gene knock-outs, microbial exert effects also dark. Interestingly, some switch their attitude towards plants dependence illumination dark conditions as much may symbiotic pathogenic. This review summarizes current knowledge about roles plant-associated bacteria aiming at identification common traits general working ideas. Still, reports on infection restricted description macroscopically observable phenomena, whereas detailed information molecular level, e.g., protein-protein interaction during signal transduction induction mechanisms infectivity/virulence initiation remains sparse. As it becomes apparent from still only few studies, photoreceptors, red- blue sensitive groups interact modulate individual effects. The topic is great relevance, even economic terms, referring plant-pathogen plant-symbionts interactions, considering increasing usage artificial greenhouses, possible light-regulation synthesis plant-growth stimulating substances herbicides by certain symbionts, biocontrol pests selected a sustainable agriculture.

Language: Английский

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Comparative analysis of two paradigm bacteriophytochromes reveals opposite functionalities in two-component signaling

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: July 20, 2021

Bacterial phytochrome photoreceptors usually belong to two-component signaling systems which transmit environmental stimuli a response regulator through histidine kinase domain. Phytochromes switch between red light-absorbing and far-red states. Despite exhibiting extensive structural responses during this transition, the model bacteriophytochrome from Deinococcus radiodurans (DrBphP) lacks detectable activity. Here, we resolve long-standing conundrum by comparatively analyzing interactions output activities of DrBphP Agrobacterium fabrum (Agp1). Whereas Agp1 acts as conventional kinase, identify light-sensitive phosphatase. While binds its cognate only transiently, does so strongly, is rationalized at level. Our data pinpoint two key residues affecting balance phosphatase activities, immediately bears on photoreception signaling. The opposing in highly similar bacteriophytochromes suggest use light-controllable kinases phosphatases for optogenetics.

Language: Английский

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Structural mechanism of signal transduction in a phytochrome histidine kinase

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Dec. 12, 2022

Abstract Phytochrome proteins detect red/far-red light to guide the growth, motion, development and reproduction in plants, fungi, bacteria. Bacterial phytochromes commonly function as an entrance signal two-component sensory systems. Despite availability of three-dimensional structures other proteins, conformational changes, which lead activation protein, are not understood. We reveal cryo electron microscopy complete phytochrome from Deinoccocus radiodurans its resting photoactivated states at 3.6 Å 3.5 resolution, respectively. Upon photoactivation, photosensory core module hardly changes tertiary domain arrangement, but connector helices between histidine kinase modules open up like a zipper, causing asymmetry disorder effector domains. The provide framework for atom-scale understanding signaling phytochromes, visualize allosteric communication over several nanometers, suggest that dimeric arrangement domains is important phosphatase activity system. results have implications optogenetic applications.

Language: Английский

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