Determinants for dephosphorylation of the RNA polymerase II C-terminal domain by Scp1.Zhang, Y., Kim, Y., Genoud, N., Gao, J., Kelly, J.W., Pfaff, S.L., Gill, G.N., Dixon, J.E., Noel, J.P.
(2006) Mol Cell 24: 759-770
- PubMed: 17157258
- DOI: 10.1016/j.molcel.2006.10.027
- Structures With Same Primary Citation
- PubMed Abstract:
Phosphorylation and dephosphorylation of the C-terminal domain (CTD) of RNA polymerase II (Pol II) represent a critical regulatory checkpoint for transcription. Transcription initiation requires Fcp1/Scp1-mediated dephosphorylation of phospho-CTD. Fc ...
Phosphorylation and dephosphorylation of the C-terminal domain (CTD) of RNA polymerase II (Pol II) represent a critical regulatory checkpoint for transcription. Transcription initiation requires Fcp1/Scp1-mediated dephosphorylation of phospho-CTD. Fcp1 and Scp1 belong to a family of Mg2+ -dependent phosphoserine (P.Ser)/phosphothreonine (P.Thr)-specific phosphatases. We recently showed that Scp1 is an evolutionarily conserved regulator of neuronal gene silencing. Here, we present the X-ray crystal structures of a dominant-negative form of human Scp1 (D96N mutant) bound to mono- and diphosphorylated peptides encompassing the CTD heptad repeat (Y1S2P3T4S5P6S7). Moreover, kinetic and thermodynamic analyses of Scp1-phospho-CTD peptide complexes support the structures determined. This combined structure-function analysis discloses the residues in Scp1 involved in CTD binding and its preferential dephosphorylation of P.Ser5 of the CTD heptad repeat. Moreover, these results provide a template for the design of specific inhibitors of Scp1 for the study of neuronal stem cell development.
Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, California 92037. Electronic address: email@example.com.