Abstract
Translationally competent mRNAs form a closed loop via interaction of initiation factors with the 5′ cap and poly(A) tail. However, many viral mRNAs lack a cap and/or a poly(A) tail. We show that an uncapped, nonpolyadenylated plant viral mRNA forms a closed loop by direct base-pairing (kissing) of a stem loop in the 3′ untranslated region (UTR) with a stem loop in the 5′ UTR. This allows a sequence in the 3′ UTR to confer translation initiation at the 5′-proximal AUG. This base-pairing is also required for replication. Unlike other cap-independent translation mechanisms, the ribosome enters at the 5′ end of the mRNA. This remarkably long-distance base-pairing reveals a novel mechanism of cap-independent translation and means by which mRNA UTRs can communicate.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
