Reassessing apoptosis in plants


Cell death can be driven by a genetically programmed signalling pathway known as programmed cell death (PCD). In plants, PCD occurs during development as well as in response to environmental and biotic stimuli. Our understanding of PCD regulation in plants has advanced significantly over the past two decades; however, the molecular machinery responsible for driving the system remains elusive. Thus, whether conserved PCD regulatory mechanisms include plant apoptosis remains enigmatic. Animal apoptotic regulators, including Bcl-2 family members, have not been identified in plants but expression of such regulators can trigger or suppress plant PCD. Moreover, plants exhibit nearly all of the biochemical and morphological features of apoptosis. One difference between plant and animal PCD is the absence of phagocytosis in plants. Evidence is emerging that the vacuole may be key to removal of unwanted plant cells, and may carry out functions that are analogous to animal phagocytosis. Here, we provide context for the argument that apoptotic-like cell death occurs in plants.

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Fig. 1: Comparison of apoptotic-like cell death in animal and plant cells.
Fig. 2: Apoptotic bodies in plant PCD and structural conservation of human and Arabidopsis BAG4 BAG domains.


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Research in the Dickman lab is supported by BARD and NSF. B.W. is supported by a QUT Vice Chancellor’s Research Fellowship. P.d.F. is supported by grants from the Texas A&M University – CAPES program, the Texas A&M - Conacyt program, the National Science Foundation, the National Institutes of Health and the Qatar National Research Foundation. T.J.W. is supported in part by the Agriculture and Food Research Initiative Competitive Grants Program Grant no. 2016-67013-24736 from the USDA National Institute of Food and Agriculture.

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M.D., B.W., Y.L., P.d.F. and T.W. wrote the article. P.d.F., B.W. and Y.L. prepared the figures.

Correspondence to Martin Dickman or Brett Williams.

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Dickman, M., Williams, B., Li, Y. et al. Reassessing apoptosis in plants. Nature Plants 3, 773–779 (2017).

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