Cell-to-Cell Movement of Homeodomain Transcription Factors: Yesterday, Today and Tomorrow

  • Xianfeng Morgan Xu
  • Dave Jackson
Part of the Advances in Plant Biology book series (AIPB, volume 3)


Cell-to-cell communication is pivotal for the coordinated behavior of cells, and thus the orchestrated development of any multicellular organism. One special means of communication is the direct transfer of macromolecules, including transcription factors, between plant cells through plasmodesmata. KNOTTED1 (KN1), a maize homeodomain transcription factor, was the first plant protein identified to traffic between cells. KN1 belongs to a family of essential proteins functioning during stem cell maintenance in the shoot apical meristem. Here we recall the history of the remarkable finding of KN1 trafficking, and summarize our current understanding of its mechanism, regulation and potential significance. We also touch upon some of the important questions remaining for future exploration.


Shoot Apical Meristem Fluorescence Recovery After Photobleaching Homeodomain Protein Size Exclusion Limit KNOX Protein 
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.



Thanks to Kate Creasey for critical reading. X. M. X. is a LSRF Fellow of the Life Sciences Research Foundation and a Chapman Fellow of the Chapman Foundation. Relevant research in the authors’ laboratory is supported by the National Science Foundation (award 1027003).


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Cold Spring Harbor LaboratoryCold Spring HarborUSA

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