title: Identification of Arbuscular Mycorrhiza (AM)-Responsive microRNAs in Tomato.
abstract: A majority of land plants can form symbiosis with arbuscular mycorrhizal (AM) fungi. MicroRNAs (miRNAs) have been implicated to regulate this process in legumes, but their involvement in non-legume species is largely unknown. In this study, by performing deep sequencing of sRNA libraries in tomato roots and comparing with tomato genome, a total of 700 potential miRNAs were predicted, among them, 187 are known plant miRNAs that have been previously deposited in miRBase. Unlike the profiles in other plants such as rice and Arabidopsis, a large proportion of predicted tomato miRNAs was 24 nt in length. A similar pattern was observed in the potato genome but not in tobacco, indicating a Solanum genus-specific expansion of 24-nt miRNAs. About 40% identified tomato miRNAs showed significantly altered expressions upon Rhizophagus irregularis inoculation, suggesting the potential roles of these novel miRNAs in AM symbiosis. The differential expression of five known and six novel miRNAs were further validated using qPCR analysis. Interestingly, three up-regulated known tomato miRNAs belong to a known miR171 family, a member of which has been reported in Medicago truncatula to regulate AM symbiosis. Thus, the miR171 family likely regulates AM symbiosis conservatively across different plant lineages. More than 1000 genes targeted by potential AM-responsive miRNAs were provided and their roles in AM symbiosis are worth further exploring.
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Laboratory of Plant Genetics and Molecular Evolution, School of Life Sciences, Nanjing University Nanjing, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Laboratory of Plant Genetics and Molecular Evolution, School of Life Sciences, Nanjing University Nanjing, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Laboratory of Plant Genetics and Molecular Evolution, School of Life Sciences, Nanjing University Nanjing, China.
authors.forename: Cheng-Chen
authors.initials: CC
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Laboratory of Plant Genetics and Molecular Evolution, School of Life Sciences, Nanjing University Nanjing, China.
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Laboratory of Plant Genetics and Molecular Evolution, School of Life Sciences, Nanjing University Nanjing, China.
authors.forename: Fang-Fang
authors.initials: FF
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Laboratory of Plant Genetics and Molecular Evolution, School of Life Sciences, Nanjing University Nanjing, China.
authors.forename: Xiao-Yi
authors.initials: XY
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Laboratory of Plant Genetics and Molecular Evolution, School of Life Sciences, Nanjing University Nanjing, China.
authors.forename: Mian
authors.initials: M
authors.lastname: Wu
authors.affiliation: Institute of Botany, Jiangsu Province and Chinese Academy of Sciences Nanjing, China.
authors.forename: Yue-Yu
authors.initials: YY
authors.lastname: Hang
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Laboratory of Plant Genetics and Molecular Evolution, School of Life Sciences, Nanjing University Nanjing, China.
authors.forename: Jian-Qun
authors.initials: JQ
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Laboratory of Plant Genetics and Molecular Evolution, School of Life Sciences, Nanjing University Nanjing, China.
authors.forename: Zhu-Qing
authors.initials: ZQ
authors.lastname: Shao
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Laboratory of Plant Genetics and Molecular Evolution, School of Life Sciences, Nanjing University Nanjing, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
keywords: MicroRNAs; Rhizophagus irregularis; arbuscular mycorrhiza symbiosis; deep sequencing analysis; tomato