Live-cell single-molecule dynamics of eukaryotic RNA polymerase machineries
Summary
Eukaryotic gene expression is orchestrated by RNA polymerases (RNAPI, II, and III) and associated factors, yet their real-time dynamics remain obscure. Using single-molecule tracking in living yeast, we quantified the kinetics of 58 proteins encompassing three RNAP machineries. RNAPI and RNAPIII preinitiation complexes (PICs) engage in long-lived chromatin interactions, contrasting with transient RNAPII PICs. We further report kinetics of RNAPII-associated factors for elongation, histone m
Content
# Live-cell single-molecule dynamics of eukaryotic RNA polymerase machineries
*Published: 2026 Mar 19*
Eukaryotic gene expression is orchestrated by RNA polymerases (RNAPI, II, and
III) and associated factors, yet their real-time dynamics remain obscure. Using
single-molecule tracking in living yeast, we quantified the kinetics of 58
proteins encompassing three RNAP machineries. RNAPI and RNAPIII preinitiation
complexes (PICs) engage in long-lived chromatin interactions, contrasting with
transient RNAPII PICs. We further report kinetics of RNAPII-associated factors
for elongation, histone modification, C-terminal domain (CTD) modification, RNA
processing, and termination. Many elongation factors show brief rather than
persistent association, suggesting dynamic interactions with factor exchange and
allowing a potential repertoire of regulatory events. CTD truncation reduces U1
small nuclear ribonucleoprotein residence time and intron retention in ribosomal
protein genes, providing insights into cotranscriptional splicing. Our findings
establish a framework of dynamic interactions of RNAP machineries.
DOI: 10.1126/science.ads0960