Source 1primary paper2001Proceedings of the National Academy of Sciences
Toolkit/Avena sativa phototropin LOV2 domain
Avena sativa phototropin LOV2 domain
Also known as: LOV2 domain, recombinant LOV2 domain of A. sativa phototropin
Taxonomy: Mechanism Branch / Component. Workflows sit above the mechanism and technique branches rather than replacing them.
Summary
The Avena sativa phototropin LOV2 domain is a recombinant blue-light-sensing protein domain that binds flavin mononucleotide (FMN) and undergoes a reversible light-triggered conformational change. Blue light induces formation of a cysteinyl-FMN adduct, and the adduct spontaneously reverses in the dark, enabling optomechanical signal transduction.
Usefulness & Problems
Why this is useful
This domain is useful as a compact light-responsive module for controlling protein conformation with blue light through an intrinsic FMN-based photochemical cycle. The cited work supports its role as an optomechanical transducer and proposes that its conformational change can modulate signaling output toward kinase autophosphorylation.
Problem solved
It addresses the problem of converting a defined optical input into a reversible protein conformational change within a genetically encoded sensory domain. The source specifically links this change to proposed transmission of light signals to the phototropin kinase region.
Problem links
Need conditional control of signaling activity
DerivedThe Avena sativa phototropin LOV2 domain is a blue-light-sensing protein domain that binds flavin mononucleotide (FMN) and undergoes a light-triggered conformational change. In this domain, blue light induces a reversible cysteinyl-FMN adduct that functions as an optomechanical transducer for signaling.
Need precise spatiotemporal control with light input
DerivedThe Avena sativa phototropin LOV2 domain is a blue-light-sensing protein domain that binds flavin mononucleotide (FMN) and undergoes a light-triggered conformational change. In this domain, blue light induces a reversible cysteinyl-FMN adduct that functions as an optomechanical transducer for signaling.
Taxonomy & Function
Primary hierarchy
Mechanism Branch
Component: A low-level protein part used inside a larger architecture that realizes a mechanism.
Mechanisms
conformational uncagingconformational uncagingConformational Uncagingdark-state spontaneous adduct reversaldark-state spontaneous adduct reversallight-induced cysteinyl-fmn adduct formationlight-induced cysteinyl-fmn adduct formationTechniques
No technique tags yet.
Target processes
signalingInput: Light
Implementation Constraints
cofactor dependency: cofactor requirement unknownencoding mode: genetically encodedimplementation constraint: context specific validationimplementation constraint: spectral hardware requirementoperating role: regulatorswitch architecture: uncaging
The domain requires FMN as chromophore, and the evidence specifically describes recombinant LOV2 reconstitution with various 13C/15N-labeled FMN isotopomers. Practical use therefore depends on cofactor incorporation and blue-light irradiation, but the provided evidence does not specify construct architecture, host system, or illumination parameters beyond blue light.
The supplied evidence is limited to one source focused on photochemistry and conformational response, with mechanistic signaling to the kinase domain presented as a proposal rather than direct functional proof. No quantitative kinetics, dynamic range, expression performance in heterologous systems, or application-specific engineering data are provided here.
Validation
Cell-freeBacteriaMammalianMouseHumanTherapeuticIndep. Replication
Supporting Sources
Ranked Claims
Light-driven flavin adduct formation in the Avena sativa phototropin LOV2 domain results in conformational modification.
The light-driven flavin adduct formation results in conformational modification, which was diagnosed by (1)H and (31)P NMR spectroscopy.
The observed conformational change is proposed to initiate light-signal transmission through conformational modulation of the protein kinase domain conducive to autophosphorylation of NPH1.
This conformational change is proposed to initiate the transmission of the light signal via conformational modulation of the protein kinase domain conducive to autophosphorylation of NPH1.
Blue light irradiation causes addition of cysteine 450 thiol to the 4a position of the FMN chromophore in the Avena sativa phototropin LOV2 domain.
Blue light irradiation is shown to result in the addition of a thiol group (cysteine 450) to the 4a position of the FMN chromophore.
The light-induced flavin adduct in the Avena sativa phototropin LOV2 domain reverts spontaneously in the dark by elimination.
The adduct reverts spontaneously in the dark by elimination.
Approval Evidence
1 source4 linked approval claimsfirst-pass slug avena-sativa-phototropin-lov2-domain
We have reconstituted a recombinant LOV2 domain of A. sativa phototropin with various (13)C/(15)N-labeled isotopomers of the cofactor, FMN.
Source:
conformational changesupports
Light-driven flavin adduct formation in the Avena sativa phototropin LOV2 domain results in conformational modification.
The light-driven flavin adduct formation results in conformational modification, which was diagnosed by (1)H and (31)P NMR spectroscopy.
Source:
mechanistic proposalsupports
The observed conformational change is proposed to initiate light-signal transmission through conformational modulation of the protein kinase domain conducive to autophosphorylation of NPH1.
This conformational change is proposed to initiate the transmission of the light signal via conformational modulation of the protein kinase domain conducive to autophosphorylation of NPH1.
Source:
photochemical mechanismsupports
Blue light irradiation causes addition of cysteine 450 thiol to the 4a position of the FMN chromophore in the Avena sativa phototropin LOV2 domain.
Blue light irradiation is shown to result in the addition of a thiol group (cysteine 450) to the 4a position of the FMN chromophore.
Source:
reversibilitysupports
The light-induced flavin adduct in the Avena sativa phototropin LOV2 domain reverts spontaneously in the dark by elimination.
The adduct reverts spontaneously in the dark by elimination.
Source:
Comparisons
Source-backed strengths
The domain has a chemically defined mechanism in which blue light drives addition of Cys450 thiol to the 4a position of FMN, directly coupling photon absorption to structural change. Its signaling state is reversible because the flavin adduct decays spontaneously in the dark, and recombinant reconstitution with isotopically labeled FMN has been demonstrated.
Compared with Avena sativa phototropin-1 LOV2 domain
Avena sativa phototropin LOV2 domain and Avena sativa phototropin-1 LOV2 domain address a similar problem space because they share signaling.
Shared frame: same top-level item type; shared target processes: signaling; shared mechanisms: conformational uncaging, conformational_uncaging; same primary input modality: light
Relative tradeoffs: appears more independently replicated; looks easier to implement in practice.
Compared with light-harvesting complex II
Avena sativa phototropin LOV2 domain and light-harvesting complex II address a similar problem space because they share signaling.
Shared frame: same top-level item type; shared target processes: signaling; shared mechanisms: conformational_uncaging; same primary input modality: light
Relative tradeoffs: appears more independently replicated; looks easier to implement in practice.
Compared with photoswitchable inhibitory peptides
Avena sativa phototropin LOV2 domain and photoswitchable inhibitory peptides address a similar problem space because they share signaling.
Shared frame: same top-level item type; shared target processes: signaling; shared mechanisms: conformational uncaging, conformational_uncaging; same primary input modality: light
Ranked Citations
- 1.