title: The mRNA capping enzyme of Saccharomyces cerevisiae has dual specificity to interact with CTD of RNA Polymerase II.
abstract: RNA Polymerase II (RNAPII) uniquely possesses an extended carboxy terminal domain (CTD) on its largest subunit, Rpb1, comprising a repetitive Tyr1Ser2Pro3Thr4 Ser5Pro6Ser7 motif with potential phosphorylation sites. The phosphorylation of the CTD serves as a signal for the binding of various transcription regulators for mRNA biogenesis including the mRNA capping complex. In eukaryotes, the 5 prime capping of the nascent transcript is the first detectable mRNA processing event, and is crucial for the productive transcript elongation. The binding of capping enzyme, RNA guanylyltransferases to the transcribing RNAPII is known to be primarily facilitated by the CTD, phosphorylated at Ser5 (Ser5P). Here we report that the Saccharomyces cerevesiae RNA guanylyltransferase (Ceg1) has dual specificity and interacts not only with Ser5P but also with Ser7P of the CTD. The Ser7 of CTD is essential for the unconditional growth and efficient priming of the mRNA capping complex. The Arg159 and Arg185 of Ceg1 are the key residues that interact with the Ser5P, while the Lys175 with Ser7P of CTD. These interactions appear to be in a specific pattern of Ser5PSer7PSer5P in a tri-heptad CTD (YSPTSPPS YSPTSPSP YSPTSPPS) and provide molecular insights into the Ceg1-CTD interaction for mRNA transcription.
authors: Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Lucknow, PIN 226 031, India.
authors: Akhilendra Pratap
authors: AP
authors: Bharati
authors: Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Lucknow, PIN 226 031, India.
authors: Neha
authors: N
authors: Singh
authors: Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Lucknow, PIN 226 031, India.
authors: Vikash
authors: V
authors: Kumar
authors: Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Lucknow, PIN 226 031, India.
authors: Md
authors: M
authors: Kashif
authors: Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Lucknow, PIN 226 031, India.
authors: Amit Kumar
authors: AK
authors: Singh
authors: Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Lucknow, PIN 226 031, India.
authors: Priyanka
authors: P
authors: Singh
authors: Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Lucknow, PIN 226 031, India.
authors: Sudhir Kumar
authors: SK
authors: Singh
authors: Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Lucknow, PIN 226 031, India.
authors: Mohammad Imran
authors: MI
authors: Siddiqi
authors: Molecular and Structural Biophysics Laboratory, Department of Biochemistry, North-Eastern Hill University, Shillong, PIN 793022, India.
authors: Timir
authors: T
authors: Tripathi
authors: Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Lucknow, PIN 226 031, India.
authors: Md Sohail
authors: MS
authors: Akhtar
mesh_terms: D020816:Amino Acid Motifs; D016880:Anisotropy; D001665:Binding Sites; D056004:Molecular Dynamics Simulation; D009154:Mutation; D009713:Nucleotidyltransferases / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding; D000072417:Protein Domains; D055503:Protein Multimerization; D012319:RNA Polymerase II / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D012694:Serine / Q000737:chemistry; D015398:Signal Transduction; D013050:Spectrometry, Fluorescence; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques; D000098556:mRNA Guanylyltransferases
chemical_list: D012333:RNA, Messenger; D012694:Serine; D009713:Nucleotidyltransferases; D012319:RNA Polymerase II; D000098556:mRNA Guanylyltransferases