Unraveling the phospholipid identity of the gene expression compartments by single molecule localization microscopy

0555844 - ÚMG 2022 RIV CZ eng O - Others
Hoboth, Peter - Sztacho, Martin - Šebesta, O. - Hozák, Pavel
Unraveling the phospholipid identity of the gene expression compartments by single molecule localization microscopy.
2021
R&D Projects: GA ČR GA19-05608S; GA ČR(CZ) GA18-19714S; GA MŠMT LTC19048; GA MŠMT LTC20024; GA MŠMT(CZ) ED1.1.00/02.0109; GA MŠMT(CZ) LM2018129; GA MŠMT(CZ) EF16_013/0001775
Research Infrastructure: Czech-BioImaging II - 90129
Institutional support: RVO:68378050
Keywords : single-molecule localization microscopy * nuclear phosphatidylinositol phosphates * nucleoplasm * nuclear speckles * RNA polymerase II transcription
OECD category: Cell biology

Current models of gene expression acknowledge protein clustering and formation of transcriptional condensates as a driving force of gene expression. These models are mostly based on single-molecule localization microscopy (SMLM) which provided an unprecedented insight into the sub-nuclear organization of proteins and nucleic acids. However, the roles of nuclear lipids in the establishment of the functional nuclear architecture, apart from the nuclear envelope, has been neglected. Nevertheless, accumulating evidence suggests the involvement of nuclear lipids and particularly of phosphatidylinositol phosphates (PIPs) in gene expression. We used quantitative SMLM for the evaluation of the nuclear PIP distribution while preserving the context of nuclear architecture. We showed phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), phosphatidylinositol 3,4-bisphosphate (PI(3,4)P2) and phosphatidylinositol 4-monophosphate (PI(4)P) within nuclear speckles 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 RNA polymerase II (RNAPII) foci either in the nucleoplasm or nuclear speckles. We continue to uncover the PIP fingerprints in the subsequent stages of RNAPII transcription. Our efforts aim at elucidating the roles of nuclear PIPs in the compartmentalization of gene expression.
Permanent Link: http://hdl.handle.net/11104/0330301