HSP90 and its R2TP/Prefoldin-like cochaperone are involved in the cytoplasmic assembly of RNA polymerase II.

@article{Boulon2010HSP90AI,
  title={HSP90 and its R2TP/Prefoldin-like cochaperone are involved in the cytoplasmic assembly of RNA polymerase II.},
  author={S{\'e}verine Boulon and B{\'e}reng{\`e}re Pradet-Balade and C{\'e}line Verheggen and Doroth{\'e}e Molle and St{\'e}phanie Boireau and Marya Georgieva and Karim Azzag and Marie-C{\'e}cile Robert and Yasmeen Ahmad and Henry Neel and Angus I. Lamond and Edouard Bertrand},
  journal={Molecular cell},
  year={2010},
  volume={39 6},
  pages={
          912-924
        }
}

Figures from this paper

Rtp1p Is a Karyopherin-Like Protein Required for RNA Polymerase II Biogenesis
TLDR
Rtp1p is defined as a new component of the RNA pol II biogenesis machinery that plays roles in subunit assembly and likely in transport through the nuclear pore complex.
Proteomic Analysis Reveals a Role for the GTPase RPAP4/GPN1 and the Cochaperone RPAP3 in Biogenesis of All Three Nuclear RNA Polymerases
TLDR
A model in which biogenesis of RNAP I, II and III is integrated through the action of assembly and nuclear import factors is presented, suggesting that all three nuclear RNAPs may be coupled.
Nuclear import of RNA polymerase II is coupled with nucleocytoplasmic shuttling of the RNA polymerase II-associated protein 2
TLDR
The results have important implications, as they indicate that RPAP2 controls gene expression by two distinct mechanisms, one that targetsRNAP II activity during transcription and the other that controls availability of RNAP II in the nucleus.
Gpn2 and Rba50 Directly Participate in the Assembly of the Rpb3 Subcomplex in the Biogenesis of RNA Polymerase II
TLDR
It is concluded that Gpn2 and Rba50 directly participate in the assembly of the Rpb3 subcomplex and subsequently the biogenesis of RNAPII.
Rpb5, a subunit shared by eukaryotic RNA polymerases, cooperates with prefoldin-like Bud27/URI.
TLDR
Details about subunit Rpb5’s structure, conservation and the role it plays in transcription regulation are provided by analyzing the different interactions with several factors, as well as its participation in the assembly of the three RNA pols, in cooperation with prefoldin-like Bud27/URI.
A nuclear proteome localization screen reveals the exquisite specificity of Gpn2 in RNA polymerase biogenesis
TLDR
Overall, this screen shows the exquisite specificity of GPN2 for RNA polymerase transport, and reveals a previously unappreciated role for CTD modification in RNAPII nuclear localization.
The yeast prefoldin-like URI-orthologue Bud27 associates with the RSC nucleosome remodeler and modulates transcription
TLDR
Evidence of Bud27 modulating RNA pol II transcription elongation is presented and it is suggested that Bud27, in addition of contributing to Rpb5 folding within the RNA polymerases, also participates in the correct assembly of other chromatin-associated protein complexes, such as RSC, thereby modulating their activity.
The Prefoldin Bud27 Mediates the Assembly of the Eukaryotic RNA Polymerases in an Rpb5-Dependent Manner
TLDR
Evidence is shown that Bud27 is the first example of a protein that participates in the biogenesis of the three eukaryotic RNA polymerases and the first examples of aprotein modulating their assembly instead of their nuclear transport, and the role of URI seems to be conserved in humans, suggesting conserved mechanisms in RNA pols biogenesis.
HSP90 and the R2TP co-chaperone complex: Building multi-protein machineries essential for cell growth and gene expression
TLDR
The assembly of RNA polymerases in bacteria and eukaryotes, the role of HSP90/R2TP in this process and in the assembly of snoRNPs and the PIKK family of TORC1 kinase are discussed and the roles of R2TP as a master regulator of cell growth under normal or pathological conditions are speculated on.
...
...

References

SHOWING 1-10 OF 48 REFERENCES
RPAP1, a Novel Human RNA Polymerase II-Associated Protein Affinity Purified with Recombinant Wild-Type and Mutated Polymerase Subunits
TLDR
A role forRPAP1 in RNAPII transcription was established by shutting off the synthesis of Ydr527wp, a Saccharomyces cerevisiae protein homologous to RPAP1, and demonstrating that changes in global gene expression were similar to those caused by the loss of the yeastRNAPII subunit Rpb11.
The Hsp90 chaperone controls the biogenesis of L7Ae RNPs through conserved machinery
TLDR
Inhibition of Hsp90 in human cells prevents the accumulation of U3, U4, and telomerase RNAs and decreases the levels of newly synthesized hNop58, hNHP2, 15.5K, and SBP2, suggesting that Hsp80 may control the folding of these proteins during the formation of new RNPs.
Molecular chaperone Hsp90 stabilizes Pih1/Nop17 to maintain R2TP complex activity that regulates snoRNA accumulation
TLDR
Hsp90 and R2TP proteins are shown to affect box C/D accumulation and maintenance, especially under stress conditions, and are also involved in the proper accumulation of box H/ACA small nucleolar RNAs.
In vivo degradation of RNA polymerase II largest subunit triggered by alpha-amanitin.
TLDR
In murine fibroblasts exposure to alpha-amanitin triggered degradation of the RPB1 subunit, while other RNAPII subunits, RPB5 and RPB8, remained almost unaffected, in contrast to other inhibitors, such as actinomycin D or 5,6-dichloro-1-beta-D-ribofuranosyl-benzimidazole.
Role of p54 RNA helicase activity and its C-terminal domain in translational repression, P-body localization and assembly.
TLDR
A novel RNA helicase model is proposed, in which the D2 domain acts as a protein binding platform and the ATPase/helicase activity allows protein complex remodeling that dictates the balance between repressors and an activator of translation.
Stepwise RNP assembly at the site of H/ACA RNA transcription in human cells
TLDR
The authors' analyses indicate that NAF1 binds NAP57 and escorts it to the nascent H/ACA RNA and that GAR1 then replaces Naf1 to yield mature H/ ACA RNPs in Cajal bodies and nucleoli.
Architecture of initiation-competent 12-subunit RNA polymerase II
TLDR
A model of the complete Pol II is derived by fitting structures of the core and Rpb4/7 to a 4.2-Å crystallographic electron density map and finding that the wedge allosterically prevents entry of the promoter DNA duplex into the active center cleft and induces in two switch regions a conformation poised for template-strand binding.
Amanitin Greatly Reduces the Rate of Transcription by RNA Polymerase II Ternary Complexes but Fails to Inhibit Some Transcript Cleavage Modes*
  • M. Rudd, D. Luse
  • Biology, Chemistry
    The Journal of Biological Chemistry
  • 1996
TLDR
It is found that polymerase II ternary transcription complexes stalled by the absence of NTPs resume RNA synthesis when NTP’s and amanitin are added.
...
...