4PZ6

PCE1 guanylyltransferase bound to SER2/SER5 phosphorylated RNA pol II CTD

Summary for 4PZ6

• Entry DOI: 10.2210/pdb4pz6/pdb
• Related: 4PZ7 4PZ8
• Descriptor: mRNA-capping enzyme subunit alpha, DNA-directed RNA polymerase II subunit rpb1, GUANOSINE, ... (4 entities in total)
• Functional Keywords: nucleotidyl transferase, rna capping enzyme, rna polymerase ii, spt5, guanylation, nuclear, transferase-transcription complex, transferase/transcription
• Biological source: Schizosaccharomyces pombe (Fission yeast); More
• Cellular location: Nucleus: P40997; Nucleus (By similarity): P36594
• Total number of polymer chains: 4
• Total formula weight: 99665.59

Authors

Doamekpor, S.K.,Lima, C.D. (deposition date: 2014-03-28, release date: 2014-06-25, Last modification date: 2024-10-16)

Primary citation

Doamekpor, S.K.,Sanchez, A.M.,Schwer, B.,Shuman, S.,Lima, C.D.
How an mRNA capping enzyme reads distinct RNA polymerase II and Spt5 CTD phosphorylation codes.
Genes Dev., 28:1323-1336, 2014

PubMed Abstract: Interactions between RNA guanylyltransferase (GTase) and the C-terminal domain (CTD) repeats of RNA polymerase II (Pol2) and elongation factor Spt5 are thought to orchestrate cotranscriptional capping of nascent mRNAs. The crystal structure of a fission yeast GTase•Pol2 CTD complex reveals a unique docking site on the nucleotidyl transferase domain for an 8-amino-acid Pol2 CTD segment, S5PPSYSPTS5P, bracketed by two Ser5-PO4 marks. Analysis of GTase mutations that disrupt the Pol2 CTD interface shows that at least one of the two Ser5-PO4-binding sites is required for cell viability and that each site is important for cell growth at 37°C. Fission yeast GTase binds the Spt5 CTD at a separate docking site in the OB-fold domain that captures the Trp4 residue of the Spt5 nonapeptide repeat T(1)PAW(4)NSGSK. A disruptive mutation in the Spt5 CTD-binding site of GTase is synthetically lethal with mutations in the Pol2 CTD-binding site, signifying that the Spt5 and Pol2 CTDs cooperate to recruit capping enzyme in vivo. CTD phosphorylation has opposite effects on the interaction of GTase with Pol2 (Ser5-PO4 is required for binding) versus Spt5 (Thr1-PO4 inhibits binding). We propose that the state of Thr1 phosphorylation comprises a binary "Spt5 CTD code" that is read by capping enzyme independent of and parallel to its response to the state of the Pol2 CTD.

PubMed: 24939935
DOI: 10.1101/gad.242768.114

Experimental method

X-RAY DIFFRACTION (2.406 Å)