Nanoscale analysis of nuclear phosphatidylinositol phosphate distribution between nucleaoplasm and nuclear speckles

0555748 - ÚMG 2022 RIV CZ eng O - Ostatní výsledky
Hoboth, Peter - Sztacho, Martin - Šebesta, O. - Hozák, Pavel
Nanoscale analysis of nuclear phosphatidylinositol phosphate distribution between nucleaoplasm and nuclear speckles.
2021
Grant CEP: GA MŠMT(CZ) LM2018129; GA MŠMT(CZ) EF16_013/0001775; GA ČR GA19-05608S; GA ČR(CZ) GA18-19714S; GA MŠMT LTC19048; GA MŠMT LTC20024; GA MŠMT(CZ) ED1.1.00/02.0109
Institucionální podpora: RVO:68378050
Klíčová slova: single-molecule localization microscopy * nuclear phosphatidylinositol phosphates * nucleoplasm * RNA polymerase II transcription
Obor OECD: Cell biology

Single-molecule localization microscopy (SMLM) provided an unprecedented insight into the sub-nuclear organization of proteins and nucleic acids. However, the role of the nuclear lipids in the establishment of the functional nuclear architecture, apart from the nuclear envelope, has been neglected. Nevertheless, the roles in gene expression of the nuclear lipids and phosphatidylinositol phosphates (PIPs) in particular started to emerge. Therefore, we implemented and optimized the SMLM-based approach for the quantitative evaluation of the nuclear PIP distribution while preserving the context of nuclear architecture. We have quantitatively characterized the spatial distribution of nuclear phosphatidylinositol 4,5- and 3,4-bisphosphate (PI(4,5)P2 and PI(3,4)P2, resp.) and showed that PI(4,5)P2 and PI(3,4)P2 localize within matrix of the nuclear speckle marker SON and in the nucleoplasmic foci. Moreover, we found PI(4,5)P2 and PI(3,4)P2 in the close proximity with the subset of RNAPII foci either in the nucleoplasm or at nuclear speckles. We started to investigate the cross-talk between nucleoplasmic and nuclear speckle-associated PI(4,5)P2 and PI(3,4)P2 pools and their possible roles in the regulation of RNAPII transcription. Our preliminary data suggest that upon transcription inhibition PI(4,5)P2 and PI(3,4)P2 accumulate within nuclear speckles. Therefore, nuclear speckles could play a role in the buffering of the nuclear PIP levels and thereby possibly regulate RNAPII transcription.
Trvalý link: http://hdl.handle.net/11104/0330207