Biochemical analysis of the multifunctional vaccinia mRNA capping enzyme encoded by a temperature sensitive virus mutant.
Prior biochemical analysis of the heterodimeric vaccinia virus mRNA capping enzyme suggests roles not only in mRNA capping but also in early viral gene transcription termination and intermediate viral gene transcription initiation. Prior phenotypic characterization of Dts36, a temperature sensitive virus mutant affecting the large subunit of the capping enzyme was consistent with the multifunctional roles of the capping enzyme in vivo. We report a biochemical analysis of the capping enzyme encoded by Dts36. Of the three enzymatic activities required for mRNA capping, the guanylyltransferase and methyltransferase activities are compromised while the triphosphatase activity and the D12 subunit interaction are unaffected. The mutant enzyme is also defective in stimulating early gene transcription termination and intermediate gene transcription initiation in vitro. These results confirm that the vaccinia virus mRNA capping enzyme functions not only in mRNA capping but also early gene transcription termination and intermediate gene transcription initiation in vivo.
Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, P.O. Box 100266, Gainesville, FL 32610, United States.
Jessica
J
Tate
Department of Biological Sciences, 609 Hochstetter Hall, State University of New York at Buffalo, Buffalo, NY 14260, United States.
Rachel L
RL
Boldt
Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, P.O. Box 100266, Gainesville, FL 32610, United States.
Baron D
BD
McFadden
Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, P.O. Box 100266, Gainesville, FL 32610, United States.
Susan M
SM
D'Costa
Department of Biological Sciences, 609 Hochstetter Hall, State University of New York at Buffalo, Buffalo, NY 14260, United States.
Nicholas M
NM
Lewandowski
Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, P.O. Box 100266, Gainesville, FL 32610, United States.
Amber N
AN
Shatzer
Department of Biological Sciences, 609 Hochstetter Hall, State University of New York at Buffalo, Buffalo, NY 14260, United States.
Paul
P
Gollnick
Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, P.O. Box 100266, Gainesville, FL 32610, United States.
Richard C
RC
Condit
D000818:Animals; D002460:Cell Line; D002522:Chlorocebus aethiops; D006367:HeLa Cells; D006801:Humans; D008780:Methyltransferases / Q000235:genetics* / Q000378:metabolism; D009097:Multienzyme Complexes / Q000235:genetics*; D043583:Nucleoside-Triphosphatase / Q000378:metabolism; D009713:Nucleotidyltransferases / Q000235:genetics* / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism*; D012367:RNA, Viral / Q000235:genetics; D061785:Transcription Initiation, Genetic / Q000502:physiology*; D061806:Transcription Termination, Genetic / Q000502:physiology*; D014616:Vaccinia virus / Q000235:genetics* / Q000378:metabolism; D014764:Viral Proteins; D000098556:mRNA Guanylyltransferases
D009097:Multienzyme Complexes; D012333:RNA, Messenger; D012367:RNA, Viral; D014764:Viral Proteins; D008780:Methyltransferases; D009713:Nucleotidyltransferases; D000098556:mRNA Guanylyltransferases; D010744:Phosphoric Monoester Hydrolases; C027731:capping enzyme, vaccinia virus; D043583:Nucleoside-Triphosphatase
Capping enzyme; Transcription initiation; Transcription termination; Vaccinia virus; mRNA capping