1ta0
From Proteopedia
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| , resolution 2.1Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | and | ||||||
| Gene: | CTDSP1, NIF3, NLIIF (Homo sapiens) | ||||||
| Activity: | Phosphoprotein phosphatase, with EC number 3.1.3.16 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Three-dimensional structure of a RNA-polymerase II binding protein with associated ligand.
Overview
Recycling of RNA polymerase II (Pol II) after transcription requires dephosphorylation of the polymerase C-terminal domain (CTD) by the phosphatase Fcp1. We report the X-ray structure of the small CTD phosphatase Scp1, which is homologous to the Fcp1 catalytic domain. The structure shows a core fold and an active center similar to those of phosphotransferases and phosphohydrolases that solely share a DXDX(V/T) signature motif with Fcp1/Scp1. We demonstrate that the first aspartate in the signature motif undergoes metal-assisted phosphorylation during catalysis, resulting in a phosphoaspartate intermediate that was structurally mimicked with the inhibitor beryllofluoride. Specificity may result from CTD binding to a conserved hydrophobic pocket between the active site and an insertion domain that is unique to Fcp1/Scp1. Fcp1 specificity may additionally arise from phosphatase recruitment near the CTD via the Pol II subcomplex Rpb4/7, which is shown to be required for binding of Fcp1 to the polymerase in vitro.
About this Structure
1TA0 is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structure and mechanism of RNA polymerase II CTD phosphatases., Kamenski T, Heilmeier S, Meinhart A, Cramer P, Mol Cell. 2004 Aug 13;15(3):399-407. PMID:15304220
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