nucleic acid tertiary structure
Enable an AI agent to identify a nucleic acid's three-dimensional fold, assess evidence for its conformational state, and judge which comparisons or interventions that evidence supports.
Bundle → Layer → Finding → Questions Filled
5 bundles · 9 layers · 14 findings · 25 questions
Structural unit and topology Defines the molecular extent, connectivity, and organizational scale of the tertiary structure.
Construct and residue mapping
Connects the structural description to the actual nucleic acid material.
Molecular extent
Record strand identities, residue ranges, modifications, and differences between the studied construct and its reference molecule.
- Which DNA, RNA, or mixed strands and residue ranges constitute the structural unit? boundary
- Which source establishes the construct sequence, modifications, strand breaks, and residue numbering? provenance
Connectivity and organizational scale
Separates local folding, multistrand assembly, and larger-scale organization.
Topological boundary
Record strand connectivity and justify whether linking, supercoiling, or intermolecular organization belongs within this structural unit.
- Are the strands linear, circular, nicked, or otherwise connected, and what evidence establishes that connectivity? definition
- Which intermolecular contacts or topological features belong to this fold, and which belong to a larger assembly? boundary
Fold architecture and contacts Describes the spatial organization that goes beyond a sequence or secondary-structure map.
Three-dimensional element arrangement
Positions helices, loops, junctions, and other elements relative to one another.
Spatial architecture
Record structural elements and the measurements or constraints establishing their relative placement.
- Which helices, loops, junctions, or other elements define the fold, and how are they mapped to residues? definition
- Which distances, orientations, or compactness measurements distinguish the proposed arrangement from plausible alternatives? measurement
Tertiary interaction network
Captures contacts that connect structural elements and organize the three-dimensional fold.
Contact assignment
Record candidate base interactions, stacking, backbone contacts, and other tertiary contacts with explicit assignment criteria.
- Which residue pairs or groups form proposed tertiary contacts, and what geometric or experimental criteria identify each contact? measurement
- Which contacts are directly supported, inferred from a structural model, or proposed by analogy? provenance
Stabilization and conformational change Relates fold states to solution conditions, binding partners, and perturbations.
Environment and binding
Records the conditions and associated molecules relevant to the observed conformation.
Condition-dependent fold
Associate each structural state with measured conditions and evidence for ion, ligand, or protein effects.
- Under what temperature, pH, ionic composition, concentration, and binding conditions was this state characterized? measurement
- What evidence distinguishes a specifically bound ion or ligand from a general solution effect or an uncertain assignment? provenance
Ensembles and transitions
Distinguishes alternative conformations, their populations, and supported transitions.
State populations and exchange
Record alternative states and distinguish measured heterogeneity from uncertainty in structural reconstruction.
- Which alternative conformations are supported, and are their populations or exchange times measured under comparable conditions? measurement
- Does the reported ensemble represent physical conformational variation, uncertainty in inference, or a mixture of both? boundary
- Which controlled perturbation could test a proposed transition or stabilizing interaction? action
Structural evidence and permitted inference Connects structural claims to observations, validation, and the decisions they can support.
Evidence coverage and validation
Tracks where the structure is constrained and where interpretation remains uncertain.
Claim-level structural support
Link structural assertions to experimental observations or computational predictions and record unresolved regions and validation concerns.
- Which accessible sources and underlying observations support each major architectural or contact claim? provenance
- Which residues, interactions, or relative domain positions are unresolved, weakly constrained, or affected by validation concerns? measurement
- Which reported metrics assess experimental fit, stereochemical plausibility, or prediction confidence, and what does each metric actually establish? definition
Comparison and intervention readiness
Sets the evidential requirements for comparing folds or acting on structural hypotheses.
Supported structural use
Record the intended use, comparable structural regions, and unresolved assumptions that could affect a decision.
- Which residue correspondence, atom selection, alignment procedure, and condition differences must be specified before comparing two structures? boundary
- Is the available evidence adequate for the proposed use, such as fold classification, mutation design, or binding-site investigation? action
- What additional observation would most directly resolve the uncertainty limiting that use? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these check these first hold for the sense of nucleic acid tertiary structure this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these kinds and varieties hold for the sense of nucleic acid tertiary structure this model covers, and on what evidence? provenance
Identifiers and schemes
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these identifiers and schemes hold for the sense of nucleic acid tertiary structure this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these real-world use hold for the sense of nucleic acid tertiary structure this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these failure modes and hazards hold for the sense of nucleic acid tertiary structure this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of nucleic acid tertiary structure this model covers, and on what evidence? provenance
Classifiers Filled
- Family
- Thing Registry
- Category
- Physical world and living systems
- Entry kind
- thing
- Plane
- PHY
- Domain
- PHY.OBJ
What it is Filled
Nucleic acid tertiary structure is the three-dimensional organization of a DNA or RNA molecule, including the spatial arrangement and interactions of its secondary-structure elements.
In scope
- Three-dimensional arrangement of nucleic acid helices, loops, junctions, and other structural elements
- Spatial contacts and interactions that organize a fold
- Strand connectivity, assembly boundaries, and topology relevant to the fold
- Conformational ensembles, transitions, and dependence on environmental conditions
- Experimental or computational evidence, structural coverage, and uncertainty
Out of scope
- Nucleotide sequence identity and chemical composition except where needed to map or explain a fold
- Secondary-structure descriptions considered independently of three-dimensional organization
- Protein folds and complete nucleoprotein assemblies beyond their effects on the nucleic acid conformation
- General nucleic acid synthesis, degradation, and metabolism
- Coordinate-file formats, repository operations, and software implementation
- Whole-chromosome organization except where explicitly included in the modeled structural unit
Why it exists Filled
Enable an AI agent to identify a nucleic acid's three-dimensional fold, assess evidence for its conformational state, and judge which comparisons or interventions that evidence supports.
Distinguishing features Filled
- A sequence or base-pairing diagram alone does not identify the tertiary structure: spatial organization or evidence constraining it must also be recorded.
- The same nucleotide sequence may have multiple conformations, so sequence identity is insufficient to establish structural identity.
- A coordinate model represents a proposed or measured conformation; its existence does not establish that every modeled contact occurs under the conditions of interest.
- Protein or ligand binding belongs here through its effect on nucleic acid geometry; the complete partner structure belongs to a neighboring model.
- Descriptions of DNA supercoiling or chromosome packing require an explicit structural boundary because tertiary structure and higher-order organization can overlap in usage.
What robots and AI may and may not do Filled
Must not
- Present a predicted structure as experimentally determined.
- Overstate the confidence of a structure model in reports.
- Use structural data to suggest unproven medical treatments.
- Submit structures to public databases without proper validation.
Only with a human decision
- Publishing or depositing a new structure.
- Using a structure to guide drug design decisions.
May
- Describe the tertiary structure of a DNA or RNA molecule from experimental or predicted data, naming the source.
- State the method and resolution behind a structure.
Moral aspects Filled
- Wrong structures in public databases mislead many later studies.
- Overstated claims can raise false hope in patients.
Who is affected
- Researchers
- Patients awaiting treatments
- Database users
Owners Filled
Steward
The research group that determined it; structure databases hold the public record.
Master systems
- Protein Data Bank and nucleic acid structure databases
Links to other meta-models Filled
parent
- Q3771876 - registry parent class
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.nucleic-acid-tertiary-structure
- Wikidata: Q3823894 (https://www.wikidata.org/wiki/Q3823894)
Direct properties required Filled
- Nucleic acid composition: DNA; RNA; mixed DNA-RNA; chemically modified nucleic acid
- Structural unit: Referenced molecules, strand identifiers, residue ranges, and assembly stoichiometry
- Connectivity and topology: Linear or circular strands; strand breaks; documented knot, linking, or supercoiling descriptors where applicable
- Tertiary contact network: Residue- or atom-indexed contacts with interaction type, geometric criterion, and evidence
- Global and local geometry: Distances and radius of gyration in Å or nm; angles in degrees; each with a defined atom selection
- Conformational state: Defined state identifier; single modeled conformation or ensemble; population estimates when supported
- Environmental conditions: Temperature in K or °C; pH; ion and ligand identities with concentrations in mol/L; applied force in pN when relevant
- Structural evidence and confidence: Source-linked observations, methods, residue coverage, validation metrics, and method-specific confidence measures
Recognition required Filled
- Seen only through experimental data, such as diffraction maps, cryo-electron microscopy or NMR.
- Shown as three-dimensional models of folded helices, loops and junctions.
Capabilities and actions required Filled
- Map observed or predicted spatial features to a defined nucleic acid construct.
- Compare folds using explicit residue correspondence, structural coverage, and compatible conditions.
- Locate candidate tertiary contacts and identify observations needed to test them.
- Distinguish supported conformational changes from differences attributable to construct, method, or environment.
- Propose mutations, ion changes, or binding perturbations to test a structural hypothesis.
- Assess whether a structure is sufficiently supported for a specified downstream use.
Hazards and failure modes required Filled
- Errors in models from poor data or over-fitting.
- Misinterpretation of predicted structures as facts.
Standards and interfaces required Filled
- The PDBx/mmCIF data standard, maintained by the Worldwide Protein Data Bank, specifies how deposited nucleic acid structures and their associated structural metadata are represented.
Context of use required Filled
- Nucleic acid tertiary structure is studied in structural biology to explain how DNA and RNA folding supports molecular recognition, catalysis and regulation.
- Three-dimensional models are used to compare conformations, interpret experiments and evaluate proposed interactions with proteins or other molecules.
- Any interpretation depends on the experimental conditions and the uncertainty of the structural evidence.
Sources Filled
- Wikidata item Q3823894: nucleic acid tertiary structure - identity and sense of the item
- Wikipedia: Nucleic acid tertiary structure - general description of the item
Open questions
- Does an existing Vercy world model already own this concept, requiring this registry entry to link to it instead of receiving a separate publication?
- What authoritative definition should delimit tertiary structure across DNA, RNA, multistrand folds, and higher-order nucleic acid organization?
- Which conventions should distinguish tertiary contacts from secondary-structure interactions in cases such as pseudoknots and extended noncanonical pairing?
- Which method-specific evidence and validation criteria are sufficient for each intended downstream use without treating unlike confidence metrics as interchangeable?
- How should structural states be identified across different constructs and conditions when the evidence does not establish whether they are distinct folds or variations within one ensemble?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q3823894/spec.json