The F-Actin-Binding MPRIP Forms Phase-Separated Condensates and Associates with PI(4,5)P2 and Active RNA Polymerase II in the Cell Nucleus

0554294 - ÚMG 2022 RIV CH eng J - Journal Article
Balaban, Can - Sztacho, Martin - Blažíková, Michaela - Hozák, Pavel
The F-Actin-Binding MPRIP Forms Phase-Separated Condensates and Associates with PI(4,5)P2 and Active RNA Polymerase II in the Cell Nucleus.
Cells. Roč. 10, č. 4 (2021), č. článku 848. E-ISSN 2073-4409
R&D Projects: GA ČR GA19-05608S; GA ČR(CZ) GA18-19714S; GA MŠMT(CZ) EF16_013/0001775; GA MŠMT(CZ) ED1.1.00/02.0109; GA MŠMT LTC19048; GA MŠMT LTC20024; GA MŠMT(CZ) LM2018129
Research Infrastructure: Czech-BioImaging - 90062; Czech-BioImaging II - 90129
Institutional support: RVO:68378050
Keywords : mprip * phase separation * pip2 * actin * nucleus
OECD category: Cell biology
Impact factor: 7.666, year: 2021
Method of publishing: Open access
https://www.mdpi.com/2073-4409/10/4/848

Here, we provide evidence for the presence of Myosin phosphatase rho-interacting protein (MPRIP), an F-actin-binding protein, in the cell nucleus. The MPRIP protein binds to Phosphatidylinositol 4,5-bisphosphate (PIP2) and localizes to the nuclear speckles and nuclear lipid islets which are known to be involved in transcription. We identified MPRIP as a component of RNA Polymerase II/Nuclear Myosin 1 complex and showed that MPRIP forms phase-separated condensates which are able to bind nuclear F-actin fibers. Notably, the fibrous MPRIP preserves its liquid-like properties and reforms the spherical shaped condensates when F-actin is disassembled. Moreover, we show that the phase separation of MPRIP is driven by its long intrinsically disordered region at the C-terminus. We propose that the PIP2/MPRIP association might contribute to the regulation of RNAPII transcription via phase separation and nuclear actin polymerization.
Permanent Link: http://hdl.handle.net/11104/0328928