title: Influence of the 5'-proximal elements of the 5'-untranslated region of classical swine fever virus on translation and replication.
abstract: The 5'-terminal sequence spanning nt 1-29 of the 5'-untranslated region of classical swine fever virus (CSFV) forms a 5'-proximal stem-loop structure known as domain Ia. Deletions and replacement mutations were performed to examine the role of this domain. Deletion of the 5'-proximal nucleotides and disruption of the stem-loop structure greatly increased internal ribosome entry site-mediated translation but abolished the replication of the replicons. Internal deletions resulting in a change in the size of the loop of domain Ia, and even removal of the entire domain, did not substantially change the translation activity, but reduced the replication of CSFV replicons provided the replicons contained the extreme 5'-GUAU terminal sequence. Internal replacements leading to a change in the nucleotide sequence of the loop did not alter the translation and replication activities of the CSFV RNA replicon, and did not influence the rescue of viruses and growth characteristics of new viruses. These results may be important for our understanding of the regulation of translation, replication and encapsidation in CSFV and other positive-sense RNA viruses.
authors.affiliation: College of Life and Environment Sciences, Shanghai Normal University, Shanghai 200234, PR China.
authors.forename: Ming
authors.initials: M
authors.lastname: Xiao
authors.affiliation: College of Life and Environment Sciences, Shanghai Normal University, Shanghai 200234, PR China.
authors.forename: Yujing
authors.initials: Y
authors.lastname: Wang
authors.affiliation: College of Life and Environment Sciences, Shanghai Normal University, Shanghai 200234, PR China.
authors.forename: Zailing
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: College of Life and Environment Sciences, Shanghai Normal University, Shanghai 200234, PR China.
authors.forename: Chengli
authors.initials: C
authors.lastname: Ding
authors.affiliation: College of Life and Environment Sciences, Shanghai Normal University, Shanghai 200234, PR China.
authors.forename: Jialin
authors.initials: J
authors.lastname: Yu
authors.affiliation: College of Life and Environment Sciences, Shanghai Normal University, Shanghai 200234, PR China.
authors.forename: Lingzhu
authors.initials: L
authors.lastname: Wan
authors.affiliation: College of Life and Environment Sciences, Shanghai Normal University, Shanghai 200234, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
mesh_terms: D020121:5' Untranslated Regions; D000818:Animals; D002460:Cell Line; D006692:Classical Swine Fever Virus / Q000235:genetics / Q000502:physiology*; D014176:Protein Biosynthesis; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism*; D011995:Recombination, Genetic; D017384:Sequence Deletion; D013552:Swine; D014779:Virus Replication
chemical_list: D020121:5' Untranslated Regions; D012367:RNA, Viral