The Protein Interaction Network of the Human Transcription Machinery Reveals a Role for the Conserved GTPase RPAP4/GPN1 and Microtubule Assembly in Nuclear Import and Biogenesis of RNA Polymerase II*

@article{Forget2010ThePI,
  title={The Protein Interaction Network of the Human Transcription Machinery Reveals a Role for the Conserved GTPase RPAP4/GPN1 and Microtubule Assembly in Nuclear Import and Biogenesis of RNA Polymerase II*},
  author={Diane Forget and Andr{\'e}e-Anne Lacombe and Philippe Cloutier and Racha Al‐Khoury and Annie Bouchard and Mathieu Lavall{\'e}e-Adam and Denis Faubert and C{\'e}lia Jeronimo and Mathieu Blanchette and Benoit Coulombe},
  journal={Molecular \& Cellular Proteomics : MCP},
  year={2010},
  volume={9},
  pages={2827 - 2839}
}
RNA polymerase II (RNAPII), the 12-subunit enzyme that synthesizes all mRNAs and several non-coding RNAs in eukaryotes, plays a central role in cell function. Although multiple proteins are known to regulate the activity of RNAPII during transcription, little is known about the machinery that controls the fate of the enzyme before or after transcription. We used systematic protein affinity purification coupled to mass spectrometry (AP-MS) to characterize the high resolution network of protein… 

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GTP-dependent Binding and Nuclear Transport of RNA Polymerase II by Npa3 Protein*
TLDR
Npa3 defines an unconventional pathway for nuclear import of RNAPII, which involves GTP-dependent binding of Npa3 to the polymerase, which is significantly increased by the addition of GTP or its slowly hydrolyzable analogue guanosine 5′-3-O-(thio)triphosphate (GTPγS).
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