Natural Sciences
Biology
Molecular Biology
ElementScope CategorySub-ItemDefinitionGene Regulation & Epigenetics
1. Domain1.1 Scope of the DomainBoundariesThe range of phenomena the science includes and excludes.Focuses on the mechanisms controlling gene expression, chromatin state, transcriptional activation/repression, epigenetic marks, and heritable regulatory patterns. Excludes protein-level functional outcomes, broad metabolic pathways, and organism-level physiology except where they directly depend on regulatory control.
ScaleThe spatial, temporal, or organizational level at which the science operates (e.g., quantum, cellular, social, cosmic).Operates at the molecular, chromatin, and nuclear scales: regulatory DNA elements, transcription factors, nucleosomes, epigenetic marks, chromatin loops, long-range interactions, and multi-minute to generational timescales for stable epigenetic inheritance.
1.2 Ontological CommitmentsEntitiesThe kinds of things assumed to exist within the domain (particles, organisms, agents, fields, etc.).Regulatory DNA sequences (promoters, enhancers, silencers, insulators), transcription factors, chromatin remodelers, nucleosomes, histones, histone modifiers, noncoding RNAs, DNA methylation machinery, and 3D chromatin structures.
PropertiesThe fundamental attributes these entities possess (mass, charge, genotype, preference, etc.).Binding affinity, transcriptional activity, chromatin accessibility, methylation levels, histone-modification states, nucleosome positioning, cooperative factor binding, and regulatory plasticity across conditions or cell types.
CategoriesThe basic ontological types used to classify domain elements (substances, processes, relations, structures).Cis-regulatory elements, trans-acting factors, activating vs repressing histone marks, open vs closed chromatin, short-term vs long-term regulation, locus-specific vs genome-wide epigenetic states, and heritable vs reversible regulatory mechanisms.
1.3 State-VariablesVariablesThe measurable or definable properties that describe system conditions.Chromatin accessibility, histone-mark densities, methylation percentages, transcription factor occupancy, enhancer–promoter interaction frequency, transcription rates, and regulatory-RNA abundance.
ParameterizationHow variables encode and represent the system’s state.Regulatory state encoded through ATAC-seq profiles, ChIP-seq enrichment, methylation maps, Hi-C contact matrices, RNA expression levels, TF-binding curves, and genome-wide annotation sets.
1.4 Admissible IdealizationsSimplificationsConceptual reductions used to make the domain tractable (point masses, rational agents, perfect gases).Treating chromatin as binary “open/closed,” collapsing complex histone codes into single activating/repressing classes, modeling transcription-factor binding with simplified kinetics, or reducing 3D genome architecture to coarse interaction domains.
Validity ConditionsThe limits and contexts in which idealizations hold or break down.Simplifications break when marks interact combinatorially, when 3D structure dominates regulation, under strong developmental or stress conditions, or when factor binding is highly cooperative or context-dependent.
1.5 Domain AssumptionsStructural AssumptionsBackground ontological stances such as determinism, continuity, randomness, discreteness.Assumes information flow from regulatory elements to transcriptional output, stable chemical behavior of epigenetic marks, continuity of chromatin remodeling, and predictable TF–DNA interaction principles.
Implicit CommitmentsUnstated but necessary assumptions that shape the field’s conceptual structure.Assumes that marks carry functional meaning, regulatory interactions are interpretable, chromatin accessibility correlates with expression capacity, and that regulatory logic can be stably represented across similar cellular contexts.
1.6 Internal Coherence RequirementsConsistencyThe demand that domain concepts do not contradict one another.Regulatory mechanisms, chromatin architecture, epigenetic marks, and transcriptional outcomes must not contradict each other across assays, sequences, or conditions.
CompatibilityThe requirement that entities, variables, and assumptions fit together into a unified descriptive framework.Entities (regulatory elements, factors, chromatin), variables (marks, accessibility), and assumptions (specificity, stability) must jointly form a unified regulatory framework explaining gene-expression control.
2. Evidence Layer2.1 Observable PhenomenaObservablesThe aspects of the domain that can produce detectable signals accessible to measurement.Detectable features include chromatin accessibility, histone marks, DNA methylation levels, transcription-factor binding, regulatory RNA abundance, enhancer–promoter interactions, transcriptional output, and chromatin compaction states.
Detection LimitsThe boundaries of what can be resolved or sensed by current instruments or methods.Limits of ATAC-seq sensitivity, minimum ChIP enrichment required for mark detection, lowest measurable methylation fraction, single-cell detection thresholds, minimal interaction frequencies detectable in Hi-C, and optical resolution of chromatin imaging.
2.2 Measurement SystemsUnitsStandardized quantifications (meters, seconds, volts, decibels, dollars, etc.) necessary for consistent comparison.Quantifications expressed in normalized read counts, fragments per kilobase (FPKM/TPM), ChIP enrichment scores, methylation percentages, accessibility indices, contact-frequency units, fluorescence intensity, and fold-change expression values.
InstrumentsDevices and tools (microscopes, spectrometers, sensors, surveys, detectors) used to produce measurements.Sequencers, qPCR machines, ChIP-seq platforms, bisulfite sequencing systems, single-molecule imaging setups, confocal microscopes, ATAC-seq workflows, Hi-C instrumentation, and platforms for CUT&RUN or CUT&Tag.
2.3 Operational DefinitionsDefinitionsTerms defined by specific measurement procedures, ensuring empirical clarity.Operational definitions for accessibility, TF occupancy, histone-mark presence, methylation status, interaction frequency, promoter activity, and enhancer strength based on assay-specific thresholds and normalization rules.
ProceduresThe explicit steps required to perform a measurement in a reproducible way.Protocol steps for ChIP, ATAC-seq, bisulfite conversion, RNA-seq library prep, Hi-C ligation workflows, immunofluorescence staining, and single-cell regulatory profiling.
2.4 Data AcquisitionProtocolsFormal processes for gathering data under controlled or standardized conditions.Controlled acquisition through sequencing runs, immunoprecipitation workflows, fragmentation and tagging, crosslinking procedures, chromatin capture steps, and standardized pipelines for replicates and controls.
SamplingRules determining which subset of the domain is measured and how representative it is.Selection strategies for genomic regions, cell types, developmental stages, environmental conditions, or single-cell subsets to ensure representativeness of regulatory or epigenetic states.
2.5 Data Character & FormatData TypesThe form raw evidence takes (time series, spectra, images, counts, qualitative records).ChIP-seq peaks, ATAC profiles, methylation maps, Hi-C matrices, RNA expression tables, TF-binding motifs, fluorescence images, and single-cell regulatory-state vectors.
ResolutionThe granularity or precision with which data is captured.Base-pair resolution for sequencing, single-nucleotide methylation resolution, kilobase-scale for Hi-C loops, single-cell resolution for scATAC/scRNA data, and imaging spatial resolution for chromatin structure.
2.6 Reliability & CalibrationCalibrationAdjustment procedures ensuring instruments produce accurate results.Normalization using spike-in controls, calibrating antibody specificity for ChIP, controlling for enzyme efficiency in bisulfite conversion, adjusting sequencing depth, and standardizing imaging intensities.
Error CharacterizationIdentification and quantification of noise, uncertainty, bias, and measurement error.Characterization of ChIP antibody bias, sequencing noise, PCR amplification artifacts, incomplete bisulfite conversion, mapping ambiguity, batch effects in regulatory assays, and variability in single-cell measurements.
3. Structural Layer3.1 Patterns & RegularitiesLaws / RelationsStable, repeatable patterns governing how observables behave across conditions.Core regulatory patterns include transcription-factor binding rules, enhancer–promoter communication, nucleosome–DNA interaction principles, histone-mark activation/repression rules, and methylation–silencing relationships.
InvariantsQuantities or properties that remain constant under transformations (symmetries, conservation laws).Stable features such as conserved regulatory motifs, persistent epigenetic marks across cell divisions, invariant chromatin domains, predictable TF-binding hierarchies, and long-term maintenance of methylation states.
3.2 Causal ArchitectureMechanismsUnderlying processes or structures that produce the observed regularities.Mechanisms include transcription-factor recruitment, chromatin remodeling, histone modification cascades, DNA methylation deposition/removal, insulator-mediated domain formation, and long-range chromatin-loop regulation.
PathwaysOrganized sequences of interactions forming a causal chain or network.Ordered chains such as signal → TF activation → DNA binding → chromatin modification → transcriptional change; or methylation loss → chromatin opening → transcription initiation; or enhancer activation → promoter engagement → gene upregulation.
3.3 Theoretical VocabularyConceptsCore terms that encode the domain’s structure (force, gene, equilibrium, field).Core terms include promoters, enhancers, silencers, insulators, chromatin accessibility, histone marks, epigenetic memory, regulatory state, TF occupancy, cis/trans regulation, and regulatory plasticity.
ClassificationsTaxonomies, categories, or typologies that organize entities and relations.Taxonomies of activating vs repressing marks, classes of regulatory elements, TF families, types of regulatory RNAs, chromatin-state models, topologically associating domains (TADs), and genome-wide regulatory categories.
3.4 Formal RepresentationsEquationsMathematical constructs expressing laws, relations, or mechanisms.Quantitative representations of TF-binding kinetics, Hill-type activation functions, methylation/demethylation rate equations, chromatin accessibility models, and statistical equations for enhancer–promoter contact probability.
ModelsStructured representations—mathematical, computational, or conceptual—used to predict and explain phenomena.Conceptual and computational models such as chromatin-state models, TF-binding thermodynamic models, stochastic transcription-bursting models, regulatory-network models, 3D genome-looping models, and epigenetic-inheritance models.
3.5 Idealized StructuresSimplified ModelsPurposeful abstractions that capture essential dynamics while omitting irrelevant detail.Simplified regulatory circuits, binary “active/inactive” promoter states, minimal histone-code categories, coarse-grained chromatin loops, reduced TF-binding motifs, and simplified methylation landscapes.
Limit ConditionsRegimes where specific models or approximations hold (classical vs. quantum, linear vs. nonlinear).Approximations hold under stable cellular conditions, moderate TF concentrations, intact chromatin structure, and typical methylation patterns; they fail under stress, developmentally dynamic states, or complex multi-factor interactions.
3.6 Integrative FrameworksUnifying TheoriesHigher-order structures that connect disparate laws or mechanisms under a coherent whole.Unifying frameworks include the regulatory logic of the central dogma, epigenetic inheritance models, sequence–structure–expression coupling, chromatin-state theory, and genome-wide regulatory network architecture.
Interdisciplinary LinksPoints where the theory connects to adjacent sciences or larger explanatory systems.Links to genetics, developmental biology, molecular biology, neuroscience, cancer biology, evolutionary biology, and systems biology through shared principles of gene control, chromatin dynamics, and information regulation.
4. Method Layer4.1 Inquiry DesignExperimental DesignStructured plans for manipulating variables to test causal claims.Manipulating regulatory elements, TF levels, chromatin states, or epigenetic marks using CRISPR editing, TF overexpression/knockdown, histone-modifier perturbation, chromatin-remodeler inhibition, or targeted methylation/demethylation.
Observational DesignSystematic approaches for gathering non-manipulated data (surveys, field studies, natural experiments).Non-manipulative approaches such as profiling native chromatin states (ATAC-seq, DNase-seq), mapping histone marks (ChIP-seq), assessing methylation, measuring TF binding, or observing natural transcriptional variation across conditions or cell types.
4.2 Testing & ValidationHypothesis TestingProcedures for evaluating whether evidence supports or contradicts specific claims.Testing claims about regulatory effects by comparing expression changes after enhancer disruption, verifying methylation–silencing relationships, validating predicted TF-binding motifs, or assessing chromatin-state transitions.
ReplicationThe requirement that results be independently reproducible under similar conditions.Repeating ChIP-seq, ATAC-seq, methylation assays, RNA expression measures, and chromatin-interaction experiments across independent replicates, batches, or laboratories to ensure robustness.
4.3 Inference & EvaluationStatistical InferenceRules for drawing conclusions from noisy or incomplete data.Inferring regulatory interactions from noisy genomic data using differential-accessibility tests, ChIP enrichment statistics, methylation distributions, expression variance models, and Bayesian regulatory-network inference.
Model ComparisonCriteria (fit, simplicity, predictive accuracy, robustness) used to evaluate competing models.Evaluating competing regulatory models based on fit to expression profiles, accuracy of TF-binding predictions, correlation with chromatin states, predictive success in perturbation experiments, and generalizability across cell types.
4.4 Error ManagementError AnalysisIdentification and quantification of random and systematic errors.Quantifying biases and errors in ChIP antibody specificity, sequencing noise, PCR amplification artifacts, mapping errors, batch effects in epigenomic assays, and stochastic variability in single-cell regulatory measurements.
Bias ControlMethods for minimizing subjective, instrumental, or procedural biases.Controlling bias through spike-in references, randomized sample handling, strict antibody validation, balanced library preparation, controlled crosslinking duration, and consistent normalization pipelines.
4.5 Adjudication & RevisionPeer ScrutinyCollective evaluation of claims through critique, review, and debate.Review by independent scientists of regulatory interpretations, chromatin maps, epigenetic claims, modeling assumptions, and methodology to verify validity and reproducibility.
Theory RevisionProcedures for modifying, replacing, or discarding models based on new evidence.Updating regulatory theories when new evidence reveals novel chromatin states, new regulatory elements, unexpected TF cooperativity, noncanonical epigenetic inheritance, or rewrites existing regulatory hierarchies.
4.6 Integrity ConditionsTransparencyRequirements to disclose methods, data, assumptions, and limitations.Full disclosure of sequencing parameters, antibody details, data-preprocessing steps, normalization methods, perturbation conditions, sample metadata, and model assumptions.
Ethical StandardsNorms ensuring responsible conduct in experimentation, data handling, and publication.Ensuring responsible handling of genomic/epigenomic data, adherence to privacy norms for human samples, accurate reporting, prevention of data manipulation, and ethical interpretation of heritable regulatory findings.