title: Identification of mRNAs that move over long distances using an RNA-Seq analysis of Arabidopsis/Nicotiana benthamiana heterografts.
abstract: Phloem is a conductive tissue that allocates nutrients from mature source leaves to sinks such as young developing tissues. Phloem also delivers proteins and RNA species, such as small RNAs and mRNAs. Intensive studies on plant systemic signaling revealed the essential roles of proteins and RNA species. However, many of their functions are still largely unknown, with the roles of transported mRNAs being particularly poorly understood. A major difficulty is the absence of an accurate and comprehensive list of mobile transcripts. In this study, we used a hetero-graft system with Nicotiana benthamiana as the recipient scion and Arabidopsis as the donor stock, to identify transcripts that moved long distances across the graft union. We identified 138 Arabidopsis transcripts as mobile mRNAs, which we collectively termed the mRNA mobilome. Reverse transcription-PCR, quantitative real-time PCR and droplet digital PCR analyses confirmed the mobility. The transcripts included potential signaling factors and, unexpectedly, more general factors. In our investigations, we found no preferred transcript length, no previously known sequence motifs in promoter or transcript sequences and no similarities between the level of the transcripts and that in the source leaves. Grafting experiments regarding the function of ERECTA, an identified transcript, showed that no function of the transcript mobilized. To our knowledge, this is the first report identifying transcripts that move over long distances using a hetero-graft system between different plant taxa.
authors.affiliation: Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan ERATO Higashiyama Live-holonics Project, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan notaguchi.michitaka@b.mbox.nagoya-u.ac.jp.
authors.forename: Michitaka
authors.initials: M
authors.lastname: Notaguchi
authors.affiliation: Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan ERATO Higashiyama Live-holonics Project, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Higashiyama
authors.affiliation: Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan ERATO Higashiyama Live-holonics Project, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan Present address: College of Bioscience and Biotechnology, Matsumoto-cho, Kasugai, 478-8501 Japan.
authors.forename: Takamasa
authors.initials: T
authors.lastname: Suzuki
mesh_terms: D017360:Arabidopsis / Q000235:genetics*; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D064593:Heterografts; D034443:RNA Transport / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D015203:Reproducibility of Results; D017423:Sequence Analysis, RNA; D014026:Nicotiana / Q000235:genetics*
chemical_list: D012333:RNA, Messenger
keywords: Graft; Long-distance transport; Mobile mRNA; Phloem; RNA-Seq