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An Argonaute protein participating in RNA-directed chromatin silencing.

In Arabidopsis thaliana, it associates with small interfering RNAs that help target RNA-directed DNA methylation. Sequence complementarity supplies specificity while partner proteins connect recognition to a chromatin modification rather than cleavage of every matching transcript. ^[ref]

Andrei Kuzmichev led a 2002 study identifying histone methyltransferase activity in a human protein complex containing Enhancer of Zeste. Biochemical isolation linked the complex to methylation of histone H3, with activity depending on an intact SET domain.^[ref]

The contribution connected a regulator of gene expression to a specific chemical activity on chromatin. Measuring a histone methylation reaction and disrupting a required domain supplied more mechanistic information than observing that two proteins occur in the same cell.

Researcher in heterochromatin. Verdel and collaborators investigated targeting by the RITS complex, connecting small-RNA-guided recognition with recruitment of chromatin-silencing machinery.^[ref]

A regulated form of cell death. Measuring it helps distinguish failed cell specification from selective loss of an already specified biological population.

Typical execution includes protease activation, chromatin changes and packaging of cellular material for removal. Clearance by other cells can limit leakage of intracellular contents. The process is therefore more specific than any observation of reduced cell number or a cell failing to divide. ^[ref]

Authors include Daniel Zilberman.

Science 299, pp. 716–719. AGO4 mutants test small-RNA-associated chromatin regulation at SUPERMAN and AtSN1.

A neurogenic transcription factor whose role in direct neuronal conversion illustrates context-dependent chromatin engagement and hierarchical factor action.^[ref]

Authors include Guillaume Andrey.

Science 340, 1234167. chromatin contact maps and regulatory perturbation distinguish the flanking limb-enhancer domains.

A kinase involved in mitotic chromosome-attachment error correction and later coordination of cytokinesis, including responses to chromatin bridges.

Bas van Steensel coauthored research on chromatin.^[ref]

The complex of DNA and associated proteins that organises nuclear genetic material and helps regulate its accessibility.

Bmi1 is a component of a Polycomb repressive complex involved in chromatin-associated gene regulation. Its roles include regulation of developmental and proliferative programmes. Use of Bmi1 expression as a lineage marker is distinct from demonstrating its biochemical function or a uniquely defined stem-cell biological population. Interpretation therefore requires both the molecular context and the labelling strategy used in a particular experiment. ^[ref]

A fly transcriptional-regulatory gene family involved in developmental and pigmentation patterns. Its interaction with developmental and chromatin regulators can affect temperature-dependent pigmentation.

Researcher in chromatin organization. Gibson and collaborators investigated intrinsic and regulated phase separation of chromatin, testing how interactions among its components can generate collective organization.^[ref]

Researcher in live-cell chromatin imaging. Robinett and collaborators used recognition between the lac operator and repressor to mark DNA regions in living cells, making chromosome organization observable through a genetically specified tag.^[ref]

A component of the active eukaryotic CMG replicative helicase.

It works with MCM2-7 and GINS in the CMG helicase. Assembly and activation of this complex connect licensed replication origins to an operating fork; the presence of one component on chromatin does not alone establish active unwinding. ^[ref]

A botanist who studied how changes in chromatin and DNA methylation affect chromosomal crossovers near centromeres.^[ref]

The propensity of a chromatin region to be reached by a specified probe or enzyme under stated conditions. Accessibility, transcription-factor occupancy and regulatory function are related but distinct.

A region or activity limiting propagation of a chromatin state. A functional boundary is demonstrated by perturbing it and measuring the resulting domain behavior, rather than merely observing an endpoint.

Enrichment of chromatin associated with a selected protein, followed by measurement of the recovered DNA. Association with a fragment need not mean direct base-specific binding; sequential enrichment can test co-association while retaining those resolution limits.

Sequencing recovered DNA to map chromatin associated with a protein or modification. antibody specificity, fragment resolution and normalization constrain interpretation.

The spatial arrangement and dynamic interactions of chromatin. Hi-C, imaging and accessibility assays measure different aspects; no one readout establishes a universal three-dimensional structure.