Movement of Macromolecules in Plant Cells Through Plasmodesmata

Movement of Macromolecules in Plant Cells Through Plasmodesmata

Richard A. Jorgensen^1*andWilliam J. Lucas^2*

¹Department of Plant Sciences and Interdisciplinary Program in Genetics, University of Arizona, Tucson, AZ 85721-0036, USA.
²Section of Plant Biology, Division of Biological Sciences, University of California, 1 Shields Avenue, Davis, CA 95616, USA.

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*Corresponding author. E-mail: raj{at}ag.arizona.edu (R.A.J.); wjlucas{at}ucdavis.edu (W.J.L.)

Animation 1. In the first animation, a schematic representation of how transport of proteins through an individual plasmodesma between plant cells may occur is depicted. Plasmodesmata are intercellular organelles in plants that allow the passage of molecules between plant cells. Movement through plasmodesmata may allow transcription factors expressed in one cell to move into adjacent cells, thereby regulating gene expression non-cell autonomously. The transcription factor to be transported first interacts with a chaperone that binds to the plasmodesmal (PD) receptor, allowing the PD-SEL (size exclusion limit) apparatus to open. The chaperone and transcription factor then move through the pore along the endoplasmic reticular membrane (ER) that traverses the pore. Once in the target cell, the transcription factor is released, translocates to the nucleus, and regulates gene expression.

These two animations would be useful in teaching plant biology or plant development or a cell biology class discussing mechanisms of intercellular transport.

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Animation 2. In the second animation, an experiment based on the work of Sessions et al. (1) that validates the movement of a transcription factor from the site of synthesis into adjacent cells is depicted. The transcription factor LEAFY (LFY) is synthesized only in Layer 1 of a genetically altered meristem and then moves through plasmodesmata into the underlying layers (L2 and L3) to influence gene transcription of the meristem. That LFY is functional after moving through plasmodesmata is demonstrated by the activation of a reporter gene that encodes an enzyme, β-glucuronidase. When X-glucuronide (X-Gluc) is added to the plant, a blue color appears in the cells that express the reporter gene.

Click the "Play" button at the bottom of the movie screen to start the animation. Click on the "Stop" button to pause the animation at any time. Resume the animation by clicking "Play" again.

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The animations were created by Carin Cain with scientific input from William J. Lucas (University of California at Davis) and Richard A. Jorgensen (University of Arizona).

Educational Details

Learning Resource Type: Animation

Context: Undergraduate upper division, graduate, professional (degree program)

Intended Users: Teacher, learner

Intended Educational Use: Teach, learn

Discipline: Cell biology, plant biology

Keywords: Signal transduction, transcription, intercellular transport

Technical Details Animation 1

Format: Gif file

Size: 630 KB

Requirements: Any Web Browser

Technical Details Animation 2

Format: Shockwave Flash Objects (swf file)

Size: 324 KB

Requirements: Macromedia Flash 5 (http://www.macromedia.com/downloads/)

Related Resources

Perspective: R. A. Jorgensen, Directed cell-to-cell movement of functional proteins: Do transcription factors double as signal molecules in plants? Sci. STKE 2000, pe2 (2000). [Abstract] [Full Text] [PDF] [Movie 1] [Movie 2]

Limits for Use

Cost: Free

Rights: This material may be downloaded for noncommercial, course-teaching purposes only, provided credit to STKE is included by listing the citation for the Teaching Resource.