Caps on Eukaryotic mRNAs

Yasuhiro Furuichi, GeneCare Research Institute Co. Ltd., Kamakura, Japan
Aaron J Shatkin, Center for Advanced Biotechnology and Medicine, Piscataway, New Jersey, USA

Published online: July 2007

DOI: 10.1002/9780470015902.a0000891.pub2

A 5¢-terminal cap is added to most eukaryotic cellular and viral pre-messenger ribonucleic acids at an early stage of transcription. Capping is essential and modulates several subsequent events in gene expression including RNA splicing, translation and stability. These and other effects involve cap-binding proteins that recognize the m7GpppN cap structure. Capping proceeds by a similar series of enzymatic steps in a wide range of systems, but differences exist between metazoans and unicellular eukaryotes and viruses, pointing to capping enzymes as potential targets for the development of novel and selective drugs against some fungal, viral and parasitic infections.

Keywords: RNA capping; RNA methylation; cap-binding proteins; translation; MRNA stability

Figure 1. Cap structure. Cap 2 m7GpppNmpNmp- showing the m7guanosine linked to the 5¢ end of the primary transcript via a 5¢–5¢ triphosphate linkage.
Figure 2. Mechanism of cap formation.
Figure 3. Viral variations: VSV mRNA capping by RNA–GDP polyribonucleotidyl transfer and utilization of m7GTP in SFV mRNA capping.
Figure 4. Initiation of influenza virus mRNA synthesis by cap snatching. Courtesy R. Krug.
Figure 5. Models of (a) cap recognition and mRNA attachment to ribosomes and (b) of ribosome recycling facilitated by the interaction of polyA- and cap-binding proteins. Panel b courtesy of N. Sonenberg.
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Related Sub-Topics:

Nucleic Acid Structure | Transcription | Transcription of DNA | Transcriptional Regulation | RNA Structure and Function | Posttranscriptional Modification | Biomolecular Interactions | Other Biomolecules: Structure, Function, Metabolism | Enzymes: Structure and Action Mechanism | Nucleic Acids: Structure, Function, Metabolism
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Article Title: Caps on Eukaryotic mRNAs
 
How to Cite close
Furuichi, Yasuhiro, and Shatkin, Aaron J(Jul 2007) Caps on Eukaryotic mRNAs. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0000891.pub2]