title: Truncated yet functional viral protein produced via RNA polymerase slippage implies underestimated coding capacity of RNA viruses.
abstract: RNA viruses use various strategies to condense their genetic information into small genomes. Potyviruses not only use the polyprotein strategy, but also embed an open reading frame, pipo, in the P3 cistron in the -1 reading frame. PIPO is expressed as a fusion protein with the N-terminal half of P3 (P3N-PIPO) via transcriptional slippage of viral RNA-dependent RNA polymerase (RdRp). We herein show that clover yellow vein virus (ClYVV) produces a previously unidentified factor, P3N-ALT, in the +1 reading frame via transcriptional slippage at a conserved G(1-2)A(6-7) motif, as is the case for P3N-PIPO. The translation of P3N-ALT terminates soon, and it is considered to be a C-terminal truncated form of P3. In planta experiments indicate that P3N-ALT functions in cell-to-cell movement along with P3N-PIPO. Hence, all three reading frames are used to produce functional proteins. Deep sequencing of ClYVV RNA from infected plants endorses the slippage by viral RdRp. Our findings unveil a virus strategy that optimizes the coding capacity.
authors.affiliation: Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Hagiwara-Komoda
authors.affiliation: Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
authors.forename: Sun Hee
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Institute for Advanced Biosciences, Keio University, Tsuruoka 997-0017, Japan.|Graduate School of Media and Governance, Keio University, Fujisawa 252-0882, Japan.
authors.forename: Masanao
authors.initials: M
authors.lastname: Sato
authors.affiliation: Iwate Biotechnology Research Center, Kitakami 024-0003, Japan.|National Institute of Advanced Industrial Science and Technology, Sapporo 062-8517, Japan.
authors.forename: Go
authors.initials: G
authors.lastname: Atsumi
authors.affiliation: Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
authors.forename: Junya
authors.initials: J
authors.lastname: Abe
authors.affiliation: Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
authors.forename: Junya
authors.initials: J
authors.lastname: Fukuda
authors.affiliation: Center for Ecological Research, Kyoto University, Otsu 520-2113, Japan.
authors.forename: Mie N
authors.initials: MN
authors.lastname: Honjo
authors.affiliation: Center for Ecological Research, Kyoto University, Otsu 520-2113, Japan.|Japan Science and Technology Agency, PRESTO, Kawaguchi 332-0012, Japan.|Faculty of Agriculture, Ryukoku University, Otsu 520-2194, Japan.
authors.forename: Atsushi J
authors.initials: AJ
authors.lastname: Nagano
authors.affiliation: Faculty of Advanced Life Science, Hokkaido University, Sapporo 060-0810, Japan.|Graduate School of Life Science, Hokkaido University, Sapporo 060-0810, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Komoda
authors.affiliation: Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.|Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
authors.forename: Kenji S
authors.initials: KS
authors.lastname: Nakahara
authors.affiliation: Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.|Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Uyeda
authors.affiliation: Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.|Graduate School of Life Science, Hokkaido University, Sapporo 060-0810, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Naito
mesh_terms: D012321:DNA-Directed RNA Polymerases / Q000235:genetics; D016366:Open Reading Frames / Q000235:genetics; D010935:Plant Diseases / Q000235:genetics / Q000821:virology*; D017800:Potyvirus / Q000235:genetics* / Q000472:pathogenicity; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics; D014026:Nicotiana / Q000235:genetics / Q000821:virology*; D014764:Viral Proteins / Q000235:genetics*
chemical_list: D014764:Viral Proteins; D012324:RNA-Dependent RNA Polymerase; D012321:DNA-Directed RNA Polymerases