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Incoming links: Gene silencing
A. J. Herr Created 2026-10-20 Updated 2026-11-05
Researcher in plant gene silencing. Herr and collaborators investigated RNA polymerase IV in silencing endogenous DNA, connecting a specialized transcription enzyme with regulation of genomic sequences.[ref]
RNA polymerase IV directs silencing of endogenous DNA by A. J. Herr and others. Title, author list and reported study
Andrew Fire Created 2026-10-20 Updated 2026-11-05
Researcher in gene silencing. Fire and collaborators demonstrated potent sequence-specific interference by double-stranded RNA in Caenorhabditis elegans, providing an experimental foundation for RNA interference.[ref]
Gene silencing 2026-11-05
Gene silencing is reduction or suppression of a gene's functional expression. It can occur at transcription through chromatin regulation or after transcription through RNA destruction or inhibition of biological translation. The common outcome does not imply that every silencing mechanism removes the DNA sequence. [ref]
Molecular Biology of the Cell, 4th edition by Bruce Alberts and others. Chapter 7, Control of Gene Expression: transcriptional repression and RNA interference
In the classic Caenorhabditis elegans experiment, double-stranded RNA produced strong, sequence-specific interference with the corresponding gene's activity. Comparing double-stranded and single-stranded inputs helped identify the effective trigger. [ref]
Potent and specific genetic interference by double-stranded RNA in Caenorhabditis elegans by Andrew Fire and others. 1998, abstract and RNA-interference experiments
A reduced protein readout alone still does not locate the step affected: transcript abundance, translation and protein turnover can each change it. H3K27 methylation 2026-11-05
H3K27 methylation is addition of one or more methyl groups to the side chain of lysine 27 in histone H3. Mono-, di- and trimethylated states are different chemical states; a measurement of one is not automatically a measurement of the others. H3K27 trimethylation is particularly associated with Polycomb-mediated gene silencing. [ref]
A mechanistic test distinguishes correlation from catalysis. A purified complex can be supplied with histones and a methyl donor to test transfer, while changing a catalytic region tests whether that activity depends on an intact enzyme. In a cell, the distribution of the mark also depends on recruitment, removal and replacement of histones, not only on total enzyme abundance.
Thomas A. Volpe Created 2026-10-20 Updated 2026-11-05
Researcher in heterochromatin. Volpe and collaborators investigated RNA interference in gene silencing and histone-H3 lysine-9 methylation, connecting small-RNA pathways with formation of a repressive chromatin state.[ref]