Cajal bodies and snRNPs - friends with benefits

@article{Stank2017CajalBA,
  title={Cajal bodies and snRNPs - friends with benefits},
  author={David Staněk},
  journal={RNA Biology},
  year={2017},
  volume={14},
  pages={671 - 679}
}
  • D. Staněk
  • Published 14 September 2016
  • Biology
  • RNA Biology
ABSTRACT Spliceosomal snRNPs are complex particles that proceed through a fascinating maturation pathway. Several steps of this pathway are closely linked to nuclear non-membrane structures called Cajal bodies. In this review, I summarize the last 20 y of research in this field. I primarily focus on snRNP biogenesis, specifically on the steps that involve Cajal bodies. I also evaluate the contribution of the Cajal body in snRNP quality control and discuss the role of snRNPs in Cajal body… 
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The results suggest a new role for TCERG1 in the formation of Cajal bodies and the biogenesis of snRNPs, which may have a functional consequence for pre-mRNA processing.
The Sm-core mediates the retention of partially-assembled spliceosomal snRNPs in Cajal bodies until their full maturation
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DIS3L2 and LSm proteins are involved in the surveillance of Sm ring-deficient snRNAs
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It is shown that snRNAs lacking the Sm ring are unstable and accumulate in P-bodies in an LSm1-dependent manner and inhibition of 5′→3′ exoribonuclease XRN1 increases association of ΔSm snRN as well as DIS3L2, which indicates competition and compensation between these two degradation enzymes.
Coilin oligomerization and remodeling by Nopp140 reveals a hybrid assembly mechanism for Cajal bodies
TLDR
It is demonstrated that the intrinsically disordered regions of Nopp140 have substantial condensation properties and suggested that Nopp 140 binding thereby remodels stable coilin oligomers to form a particle that recruits other functional components.
JCB_201701165 1..18
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Using quantitative proteomics, assembly intermediates containing PRPF8, EFT UD2, and SNR NP200 in association with the HSP90/R2TP complex, its ZNH IT2 cofactor, and additional proteins are identified and revealed new interactions between R2TP and the tuberous sclerosis complex (TSC).
SANS (USH1G) regulates pre-mRNA splicing by mediating the intra-nuclear transfer of tri-snRNP complexes
TLDR
It is shown that SANS is found in Cajal bodies and nuclear speckles, where it interacts with components of spliceosomal sub-complexes such as SF3B1 and the large splicing cofactor SON but also with PRPFs and snRNAs related to the tri-snRNP complex.
SANS (USH1G) regulates pre-mRNA splicing by mediating the intra-nuclear transfer of tri-snRNP complexes
TLDR
The first evidence that splicing deregulation may participate in the pathophysiology of Usher syndrome is provided, with links between splicing machinery components with the intrinsically disordered ciliopathy protein SANS revealed.
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TLDR
Findings that suggest a crucial role for CBs in the spliceosome cycle in which production of newsnRNPs—and perhaps regenerated snRNPs after splicing—is promoted by the concentration of substrates in this previously mysterious subnuclear organelle are reviewed.
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Of coiled bodies, gems, and salmon
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  • Biology
    Journal of cellular biochemistry
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TLDR
This review will focus on recent developments in several aspects of CB structure and function, including exciting new results on their twin organelles, called gems, and a novel hypothesis called the "salmon theory of snRNP biogenesis".
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TLDR
The data show that particular phases of the spliceosome cycle are compartmentalized in living cells, with reassembly of the tri-snRNP occurring in CBs.
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TLDR
Cellular aspects of the biogenesis of Sm-type small nuclear ribonucleoproteins involved in the export of newly transcribed small nuclear RNAs to the cytoplasm were studied, suggesting a function for Cajal bodies in the final maturation of the U2 snRNP.
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A combination of mathematical modeling and live-cell measurements was applied to determine the dynamics of small nuclear ribonucleoprotein (snRNP) formation in Cajal bodies of living cells. Our
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TLDR
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TLDR
The aim of this review is to briefly outline the structure of snRNPs and to synthesize new and exciting developments in the snRNP biogenesis pathways.
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TLDR
It is shown here that one of them, the Cajal body (CB), can be formed de novo, and it is shown that biogenesis of the CB does not follow a hierarchical assembly pathway and exhibits hallmarks of a self-organizing structure.
The integrator complex is required for integrity of Cajal bodies
TLDR
It is shown that the integrator complex is essential for integrity of the Cajal body and snRNA maturation and Cjal body homeostasis.
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