title: Functional analysis of a viroid RNA motif mediating cell-to-cell movement in Nicotiana benthamiana.
abstract: Cell-to-cell trafficking through different cellular layers is a key process for various RNAs including those of plant viruses and viroids, but the regulatory mechanisms involved are still not fully elucidated and good model systems are important. Here, we analyse the function of a simple RNA motif (termed 'loop19') in potato spindle tuber viroid (PSTVd) which is required for trafficking in Nicotiana benthamiana leaves. Northern blotting, reverse transcriptase PCR (RT-PCR) and in situ hybridization analyses demonstrated that unlike wild-type PSTVd, which was present in the nuclei in all cell types, the trafficking-defective loop19 mutants were visible only in the nuclei of upper epidermal and palisade mesophyll cells, which shows that PSTVd loop19 plays a role in mediating RNA trafficking from palisade to spongy mesophyll cells in N.benthamiana leaves. Our findings and approaches have broad implications for studying the RNA motifs mediating trafficking of RNAs across specific cellular boundaries in other biological systems.
authors.affiliation: Center for Applied Plant Sciences, Ohio State University, Columbus, OH 43210, USA.|State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.|Beijing Research Center for Agricultural Standards and Testing, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, PR China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Jiang
authors.affiliation: Beijing Research Center for Agricultural Standards and Testing, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, PR China.
authors.forename: Meng
authors.initials: M
authors.lastname: Wang
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: Shifang
authors.initials: S
authors.lastname: Li
mesh_terms: D001692:Biological Transport; D015152:Blotting, Northern; D002467:Cell Nucleus / Q000821:virology; D017403:In Situ Hybridization; D059372:Nucleotide Motifs; D059828:Plant Cells / Q000821:virology; D018515:Plant Leaves / Q000821:virology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014026:Nicotiana / Q000821:virology*; D014772:Viroids / Q000235:genetics* / Q000378:metabolism*