Signaling and Phloem-Mobile Transcripts

  • Roberto Ruiz-Medrano
  • Friedrich Kragler
  • Shmuel Wolf
Part of the Advances in Plant Biology book series (AIPB, volume 3)


Numerous studies revealed that beside viral RNAs also plant endogenous RNAs are transported from source tissue towards apical tissues in plants. Surprisingly a high number of distinct transcripts including protein coding and non-coding RNAs were shown to allocate from cell to cell and via the phloem to distant organs. These mobile RNA molecules seem to carry specific structural features allowing them to enter the phloem tissue and to hitchhike on the phloem stream delivering assimilates from mature leaves to apical tissues. Highlighting the signaling role of phloem-allocated RNAs a number of messenger RNAs and micro RNAs have been shown to act as systemic signals altering the shape of growing tissues or to facilitate adaptation to nutritional stresses. The systemic nature of RNAs challenges our classical view on how signaling systems could function. RNA mobility increases the level of complexity and, most importantly, the specificity of a systemic signaling system coordinating growth between cells and organs. In this chapter we discuss the identity and potential function of phloem-allocated RNA molecules, the factors facilitating RNA transport, and the potential role of RNA binding proteins present in the phloem stream.


Sieve Tube Sieve Element Phloem Tissue Systemic Acquire Resistance Potato Spindle Tuber Viroid 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Work in the lab of R.R.-M. was supported by funds from CONACyT (Grant No. 50769) and UC-MEXUS; FK was supported by the Project P 19682-B03 from the Austrian Science Funds (FWF). Research in the lab of S.W. was supported by the Israel Science Foundation (ISF grant number 386/06).


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Roberto Ruiz-Medrano
    • 1
  • Friedrich Kragler
    • 2
  • Shmuel Wolf
    • 3
  1. 1.Departamento de Biotecnología y BioingenieríaCentro De Investigación y de Estudios Avanzados del IPNMéxicoMexico
  2. 2.Max Planck Institute of Molecular Plant PhysiologyGolmGermany
  3. 3.The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture and the Otto Warburg Minerva Centre for Agricultural BiotechnologyThe Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture Food and EnvironmentRehovotIsrael

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