Plasmodesmata: composition, structure and trafficking

Epel, Bernard L.

doi:10.1007/978-94-011-0239-1_7

Cited by 26 publications

(38 citation statements)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, this P30 mutant retained its ability to bind p38, suggesting that the receptor and protein kinase activities are independent and may represent two distinct protein functions. We also found that this protein kinase activity required the presence of Mg 2+ but not Ca 2+ cations, indicating that it is not responsible for the general Ca 2+ -dependent protein kinase activity of plant cell walls (Epel 1994).…”

Section: Interaction With a Cell-wall-associated Receptormentioning

confidence: 76%

Tobacco mosaic virus: a pioneer to cell–to–cell movement

Citovsky

1999

Phil. Trans. R. Soc. Lond. B

View full text Add to dashboard Cite

Cell-to-cell movement of tobacco mosaic virus (TMV) is used to illustrate macromolecular tra¤c through plant intercellular connections, the plasmodesmata. This transport process is mediated by a specialized viral movement protein, P30. In the initially infected cell, P30 is produced by transcription of a subgenomic RNA derived from the invading virus. Presumably, P30 then associates with a certain proportion of the viral RNA molecules, sequestering them from replication and mediating their transport into neighbouring uninfected host cells. This nucleoprotein complex is targeted to plasmodesmata, possibly via interaction with the host cell's cytoskeleton. Prior to passage through a plasmodesma, the plasmodesmatal channel is dilated by the movement protein. It is proposed that targeting of P30-TMV RNA complexes to plasmodesmatal involves binding to a speci¢c cell-wall-associated receptor molecule. This protein, designated p38, also functions as a protein kinase, phosphorylating P30 at its carboxyterminus and minimizing P30-induced interference with plasmodesmatal permeability during viral infection.

show abstract

Section: Interaction With a Cell-wall-associated Receptormentioning

confidence: 76%

Tobacco mosaic virus: a pioneer to cell–to–cell movement

Citovsky

1999

Phil. Trans. R. Soc. Lond. B

View full text Add to dashboard Cite

show abstract

“…Namely, there are channels in the plasmodesmatal junction through which hormones and ions, such as calcium and potassium, move in a regulated manner. The structure of plasmodesmata in coleoptile nodes and mesocotyls of maize seedlings was demonstrated by Epel (1994). Momonoki (1992 and1997) suggested a more detailed explanation for the mechanism of the potentiaIgating theory that ACh may function as a regulator of the plasmodesmatal junction between cells, tissues and organs.…”

Section: Discussionmentioning

confidence: 99%

“…or apoplastic, via membrane-associated receptors, transmembranous gatable channels and/or transporters. The structure of plasmodesmata in coleoptile nodes of maize seedlings has already been demonstrated (Epel, 1994;Epel et al, 1992).…”

mentioning

confidence: 97%

Acetylcholine as a Signaling System to Environmental Stimuli in Plants: III. Asymmetric solute distribution controlled by ACh in gravistimulated maize seedlings

Momonoki

Hineno

Noguchi

1998

Plant Production Science

View full text Add to dashboard Cite

“…Although potentially powerful, this approach has so far been hampered by the small amount of protein present and the difficulty in extracting intact PD from the cell wall without subcellular contaminants (Epel 1994;Epel et al 1995). Nevertheless, proteins purified from cell walls have been used to raise antibodies, which by immunoelectron microscopy have been shown to recognize epitopes at the PD.…”

Section: Proteins Of the Pdmentioning

confidence: 99%

Signaling in plants by intercellular RNA and protein movement

Wu¹,

Weigel²,

Wigge³

2002

Genes Dev.

View full text Add to dashboard Cite

Plants and animals have had about 1.6 billion years-the time that has passed since they diverged from their last unicellular ancestor-to evolve different mechanisms for solving unique problems of development and intercellular signaling. As an example, plant cells are separated from each other by a substantial extracellular matrix, the cell wall. Although the cell wall is not impervious, it is likely to hinder cell-to-cell communication. Moreover, because plant cells cannot migrate during development, location, instead of lineage, is the primary determinant of cell fate in plants, making communication over both long and short distances essential for the coordination of plant growth. It appears that plants have significantly overcome the downside of having a cell wall by forming channels between cells to allow the transit of signaling and other important molecules. Plants may even be considered as supracellular organisms, in that whole tissues are symplastically connected. The channels that connect plant cells are called plasmodesmata (PD), and their investigation offers tantalizing clues as to how plant cells may use them to communicate with each other and to coordinate development. Although once seen as constricted channels through which only molecules <1 kD in size could pass (Terry and Robards 1987;Burnell 1988), PD have recently been shown to be far more dynamic and allow passage of both proteins and nucleic acids. Other findings, such as the observation that transcription factors can move between cells, and that RNA movement may be behind a range of long-distance signals in plants, raise further questions regarding a regulatory role of PD in development. Because of the importance of PD, we first summarize what we know about them, and then go on to discuss intercellular movement of proteins and RNA in general. Plasmodesmata UltrastructureUltrastructural studies of the PD by transmission electron microscopy (TEM) have shown them to be membrane-lined pores, with an exterior membrane contributed by the plasma membranes of the two cells connected by the PD, and a central desmotubule, derived from endoplasmic reticulum that is also contiguous between the two cells (Ding 1998). Typically, PD have a small diameter of ∼40 nm (Robards and Lucas 1990; van Bel and van Kesteren 1999), with the central desmotubule being connected to the plasma membrane via spoke-like extensions, resulting in microchannels having an estimated diameter of ∼2.5 nm (see Fig. 1). It is important to bear in mind that these measurements are all based on fixed tissue, and that nothing is known from these observations about the dynamic behavior of PD proteins.Morphologically, two distinct forms of PD have been recognized. Primary PD are formed at the cell plate, a plant-typical structure that consists of the incipient plasma membrane and cell wall synthesized during cytokinesis. Secondary PD, in contrast, are formed between existing cell walls. Both forms of PD can be either single-channels or branched. It is not known whether these different form...

show abstract

Plasmodesmata: composition, structure and trafficking

Cited by 26 publications

References 69 publications

Tobacco mosaic virus: a pioneer to cell–to–cell movement

Tobacco mosaic virus: a pioneer to cell–to–cell movement

Acetylcholine as a Signaling System to Environmental Stimuli in Plants: III. Asymmetric solute distribution controlled by ACh in gravistimulated maize seedlings

Signaling in plants by intercellular RNA and protein movement

Contact Info

Product

Resources

About