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Spatial regulation of cytoplasmic snRNP assembly at the cellular level
Malwina Hyjek1, Natalia Wojciechowska2, Magda Rudzka3
1Department of Cell Biology, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University, Lwowska 1, Toruń, 87-100, Poland Centre For Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wileńska 4, 87-100 Toruń Poland mhyjek@doktorant.umk.pl darsmol@umk.pl.
Journal of Experimental Botany
|August 31, 2015
Summary
Cytoplasmic assembly of small nuclear ribonucleoproteins (snRNPs) can occur diffusely or in distinct RNP-rich granules. This spatial regulation depends on the expression levels of Sm proteins and U snRNA.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Small nuclear ribonucleoproteins (snRNPs) are essential for pre-mRNA splicing in eukaryotes.
- The spatial organization of cytoplasmic snRNP assembly is poorly understood.
- Nuclear snRNP assembly is known to be spatially regulated.
Purpose of the Study:
- To investigate the spatial organization of cytoplasmic snRNP assembly.
- To understand how de novo snRNP formation influences cytoplasmic assembly.
- To determine the role of Sm proteins and U snRNA expression in cytoplasmic snRNP localization.
Main Methods:
- Observation of snRNP assembly in European larch microsporocytes.
- Correlation of snRNP localization with expression levels of splicing factors.
- Microscopic analysis of cytoplasmic RNP-rich granules.
Main Results:
- Cytoplasmic snRNP assembly can occur diffusely or in distinct granules.
- Diffuse assembly happens during moderate expression of splicing elements.
- Increased Sm protein and U snRNA expression leads to accumulation in snRNP-rich cytoplasmic bodies.
Conclusions:
- Cytoplasmic snRNP assembly is spatially regulated.
- Expression levels of Sm proteins and U snRNA dictate assembly localization.
- snRNP-rich cytoplasmic bodies represent a distinct mode of assembly under high expression conditions.
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