A PP2A-Integrator complex fine-tunes transcription by opposing CDK9

SUMMARY Gene expression is tightly controlled by Cyclin-dependent kinases (CDKs) which regulate the RNA Polymerase II (RNAPII) transcription cycle at discrete checkpoints. RNAPII pausing is a CDK9-controlled rate-limiting process that occurs shortly after initiation and is required for spatio-temporal control of transcription in multicellular organisms. We discovered that CDK9-mediated RNAPII pause-release is functionally opposed by a protein phosphatase 2A (PP2A) complex. PP2A dynamically competes for key CDK9 substrates, DSIF and RNAPII, and is recruited to transcription pausing sites by INTS6, a subunit of the Integrator complex. INTS6 depletion disrupts the Integrator-PP2A association and confers resistance to CDK9 inhibition. This results in unrestrained activity of CDK9 and dysregulation of acute transcriptional responses. Pharmacological PP2A activation amplifies RNAPII pausing mediated by CDK9 inhibitors and synergizes therapeutically in a model of MLL-rearranged leukemia. These data demonstrate that finely-tuned gene expression relies on the delicate balance of kinase and phosphatase activity throughout the transcription cycle.HIGHLIGHTS <jats:list list-type="bullet">Loss of INTS6 confers resistance to CDK9 inhibitionINTS6 recruits PP2A to Integrator and chromatinPP2A/INTS6 complexes functionally oppose CDK9PP2A/INTS6 fine-tune acute transcriptional responsesSynergistic anti-cancer activity between PP2A activators and CDK9 inhibitors.

Medienart:

Preprint

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

bioRxiv.org - (2021) vom: 15. Dez. Zur Gesamtaufnahme - year:2021

Sprache:

Englisch

Beteiligte Personen:

Vervoort, Stephin J. [VerfasserIn]
Welsh, Sarah A. [VerfasserIn]
Devlin, Jennifer R. [VerfasserIn]
Barbieri, Elisa [VerfasserIn]
Knight, Deborah A. [VerfasserIn]
Costacurta, Matteo [VerfasserIn]
Todorovski, Izabela [VerfasserIn]
Kearney, Conor J. [VerfasserIn]
Sandow, Jarrod J. [VerfasserIn]
Bjelosevic, Stefan [VerfasserIn]
Fan, Zheng [VerfasserIn]
Vissers, Joep H. A. [VerfasserIn]
Pavic, Karolina [VerfasserIn]
Martin, Ben P. [VerfasserIn]
Gregory, Gareth [VerfasserIn]
Kong, Isabella Y. [VerfasserIn]
Hawkins, Edwin D. [VerfasserIn]
Hogg, Simon J. [VerfasserIn]
Kelly, Madison J. [VerfasserIn]
Newbold, Andrea [VerfasserIn]
Simpson, Kaylene J. [VerfasserIn]
Kauko, Otto [VerfasserIn]
Harvey, Kieran F. [VerfasserIn]
Ohlmeyer, Michael [VerfasserIn]
Westermarck, Jukka [VerfasserIn]
Gray, Nathanael [VerfasserIn]
Gardini, Alessandro [VerfasserIn]
Johnstone, Ricky W. [VerfasserIn]

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doi:

10.1101/2020.07.12.199372

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

XBI018340296