Source 1primary paper2022Photochemical & Photobiological Sciences
Toolkit/Avena sativa LOV2 domain
Avena sativa LOV2 domain
Also known as: LOV2 domain
Taxonomy: Mechanism Branch / Component. Workflows sit above the mechanism and technique branches rather than replacing them.
Summary
The Avena sativa LOV2 domain is a light-sensing LOV photoreceptor domain whose dark-state recovery kinetics can be altered by homologous mutations in a conserved hydrophobic pocket. The available evidence supports its use as a tunable photosensory module in LOV-based and optogenetic tool design.
Usefulness & Problems
Why this is useful
This domain is useful as a photosensory module because conserved-pocket mutations were reported to change recovery kinetics after light activation. The cited literature specifically suggests that such mutations should be applicable for tuning dark recovery in optogenetic tools and LOV photoreceptors.
Source:
Given the conserved nature of the corresponding structural region, the here identified mutations should find application in dark-recovery tuning of optogenetic tools and LOV photoreceptors, alike.
Problem solved
It helps address the problem of tuning the dark-state recovery timescale of LOV photoreceptors used in engineered light-responsive systems. The evidence indicates that homologous pocket mutations can modulate kinetics in the Avena sativa LOV2 domain similarly to other LOV-family proteins.
Source:
Given the conserved nature of the corresponding structural region, the here identified mutations should find application in dark-recovery tuning of optogenetic tools and LOV photoreceptors, alike.
Taxonomy & Function
Primary hierarchy
Mechanism Branch
Component: A low-level protein part used inside a larger architecture that realizes a mechanism.
Mechanisms
dark-recovery kinetic tuning by conserved-pocket mutationdark-state recovery kinetic tuning by conserved-pocket mutationlight sensing by a lov photoreceptor domainTechniques
Structural CharacterizationTarget processes
No target processes tagged yet.
Input: Light
Implementation Constraints
The available evidence supports using homologous mutations in a conserved hydrophobic pocket to tune dark recovery in the Avena sativa LOV2 domain. However, the supplied material does not specify exact residue identities, cofactor requirements, expression systems, or construct architectures.
The supplied evidence is limited to a brief statement that homologous mutations alter kinetics and to an application-oriented claim about tool design. No quantitative kinetic values, illumination conditions, construct context, or functional validation in a specific optogenetic effector system are provided here.
Validation
Cell-freeBacteriaMammalianMouseHumanTherapeuticIndep. Replication
Supporting Sources
Ranked Claims
The identified conserved-pocket mutations should find application in dark-recovery tuning of optogenetic tools and LOV photoreceptors.
Given the conserved nature of the corresponding structural region, the here identified mutations should find application in dark-recovery tuning of optogenetic tools and LOV photoreceptors, alike.
Additional pocket mutations in PpSB1-LOV and homologous mutations in YtvA and the Avena sativa LOV2 domain produce similarly altered kinetics.
Additional mutations within the pocket of PpSB1-LOV and the introduction of homologous mutations in the LOV photoreceptor YtvA of Bacillus subtilis and the Avena sativa LOV2 domain result in similarly altered kinetics.
Approval Evidence
2 sources5 linked approval claimsfirst-pass slug avena-sativa-lov2-domain
and the Avena sativa LOV2 domain result in similarly altered kinetics
Source:
Using time-resolved vibrational spectroscopy coupled with isotope labeling, we have mapped the structural evolution of the LOV2 domain of the flavin binding phototropin Avena sativa (AsLOV2)
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application potentialsupports
The identified conserved-pocket mutations should find application in dark-recovery tuning of optogenetic tools and LOV photoreceptors.
Given the conserved nature of the corresponding structural region, the here identified mutations should find application in dark-recovery tuning of optogenetic tools and LOV photoreceptors, alike.
Source:
cross family generalizationsupports
Additional pocket mutations in PpSB1-LOV and homologous mutations in YtvA and the Avena sativa LOV2 domain produce similarly altered kinetics.
Additional mutations within the pocket of PpSB1-LOV and the introduction of homologous mutations in the LOV photoreceptor YtvA of Bacillus subtilis and the Avena sativa LOV2 domain result in similarly altered kinetics.
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residue functionsupports
Point mutagenesis testing supports a key mediating role for Q513 in the AsLOV2 allosteric model.
This model is tested through point mutagenesis, elucidating in particular the key mediating role played by Q513.
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signal propagation modelsupports
In AsLOV2, the earliest light-induced events occur in the flavin binding pocket, followed by structural changes in the beta-sheet and then alpha-helix regions, culminating in Jb1-helix unfolding that yields the signaling state.
The earliest events occur in the flavin binding pocket, where a subpicosecond perturbation of the protein matrix occurs. In this perturbed environment, the previously characterized reaction between triplet state isoalloxazine and an adjacent cysteine leads to formation of the adduct state; this step is shown to exhibit dispersive kinetics. This reaction promotes coupling of the optical excitation to successive time-dependent structural changes, initially in the b2-sheet and then b1-helix regions of the AsLOV2 domain, which ultimately gives rise to Jb1-helix unfolding, yielding the signaling state.
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structural dynamics mappingsupports
Time-resolved vibrational spectroscopy coupled with isotope labeling mapped structural evolution of AsLOV2 between 100 fs and 1 ms after optical excitation.
we have mapped the structural evolution of the LOV2 domain of the flavin binding phototropin Avena sativa (AsLOV2) over 10 decades of time, reporting structural dynamics between 100 fs and 1 ms after optical excitation
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Comparisons
Source-backed strengths
A key strength is apparent cross-family generalizability, because homologous mutations in YtvA, PpSB1-LOV, and the Avena sativa LOV2 domain were reported to produce similarly altered kinetics. This supports the conserved hydrophobic pocket as a rational target for kinetic tuning.
Ranked Citations
- 1.
Derived from 2 linked claims. Example evidence: Given the conserved nature of the corresponding structural region, the here identified mutations should find application in dark-recovery tuning of optogenetic tools and LOV photoreceptors, alike.