Gene expression
Why do identical cells make different amounts of mRNA?
Open access · cc by · source: Europe PMC
Mammalian genes switch rarely between ON and OFF, so intrinsically random transcriptional bursts create large cell-to-cell mRNA differences.
How this study connects
Role on claims
Each row is a claim on a concept or method page where this paper supports, challenges, or qualifies the statement. Roles are hand-checked — not a model guess.
Not yet placed on a claim. This paper has study layers, but no concept page yet cites it as support, challenge, or qualifier.
Discoveries this paper informs or conflicts with
- Genes fire in bursts, and the randomness is built into the gene
This paper informs this development.
Inspect source passages
Why do identical cells make different amounts of mRNA?
These passages occur verbatim in the stored paper text. They support the points listed below; they do not verify every statement in the explanation.
What drives large mammalian cell-to-cell mRNA variation here?
We have shown that the mRNA levels of both reporter genes and native genes display large cell-to-cell variations in mammalian cells due to intrinsically random, infrequent events of gene activation.
How often do genes switch between active and inactive states?
we show direct evidence that genes transition infrequently between active and inactive states, resulting in large cell-to-cell variations in gene expression in clonal cell lines.
Key findings
Genes transition infrequently between active and inactive states; bursts are intrinsically random (not mainly extrinsic) and affect whole genomic loci, including RNA polymerase II large-subunit mRNA.
Methodology
Used FISH to count individual reporter and native mRNA molecules in clonal mammalian cells and tested whether variation was intrinsic or extrinsic.
Limitations
Does not map every mammalian gene’s burst kinetics in vivo tissues, or prove a single molecular switch mechanism for all loci.
Related papers in this topic
Same topic cluster — not a recommendation engine.