Apoptotic‐like programmed cell death in plants

Abstract

Contents Summary13I.Introduction13II.Apoptotic‐like cellular destruction in plants14III.Cellular executioners18IV.Senescence‐associated PCD: a case study22V.Conclusions23Acknowledgements23References23 Summary Programmed cell death (PCD) is now accepted as a fundamental cellular process in plants. It is involved in defence, development and response to stress, and our understanding of these processes would be greatly improved through a greater knowledge of the regulation of plant PCD. However, there may be several types of PCD that operate in plants, and PCD research findings can be confusing if they are not assigned to a specific type of PCD. The various cell‐death mechanisms need therefore to be carefully described and defined. This review describes one of these plant cell‐death processes, namely the apoptotic‐like PCD (AL‐PCD). We begin by examining the hallmark ‘apoptotic‐like’ features (protoplast condensation, DNA degradation) of the cell's destruction that are characteristic of AL‐PCD, and include examples of AL‐PCD during the plant life cycle. The review explores the possible cellular ‘executioners’ (caspase‐like molecules; mitochondria; de novo protein synthesis) that are responsible for the hallmark features of the cellular destruction. Finally, senescence is used as a case study to show that a rigorous definition of cell‐death processes in plant cells can help to resolve arguments that occur in the scientific literature regarding the timing and control of plant cell death.

Lipid Peroxide-Derived Short-Chain Carbonyls Mediate Hydrogen Peroxide-Induced and Salt-Induced Programmed Cell Death in Plants

“…As judged by the morphological change and DNA fragmentation, the H 2 O 2 -and NaCl-induced PCD in this study was of the apoptosis-like mode, in which a mitochondria-dependent activation of proteases (caspaselike proteases) is involved (Reape and McCabe, 2008). In the mitochondria-dependent apoptosis in animal cells, several proteins are suggested as HNE targets, such as the Fas protein and the tumor suppressor/cell cycle regulator protein p53 (Dalleau et al, 2013), but plant cells do not have proteins apparently homologous to these HNE targets.…”

“…Thus, NaCl treatment also imposes H 2 O 2 stress on plant cells (Petrov et al, 2015). When they were stressed, both cultured cells and root cells showed TUNEL-positive nuclei, cytosolic retraction, and DNA laddering, which are typical of apoptosis-like PCD (Reape and McCabe, 2008).…”

“…Two oxidative signal pathways for PCD are reported: one is the mitochondria-dependent activation of caspaselike proteases, as in animal cell apoptosis (Reape and McCabe, 2008), and the other is the mitogen-activated Table I. Comparison of the strength of carbonyls to induce PCD in BY-2 tobacco cells as determined by DNA fragmentation Cells were incubated with a carbonyl at the indicated concentrations for 20 h. Fragmentation of the chromosomal DNA was judged based on the generation of 180 bp and its multiples by agarose gel electrophoresis.…”

“…S7C-ii) or NaCl (Supplemental Fig. S8C-ii) also indicated the occurrence of PCD (Reape and McCabe, 2008;Hogg et al, 2011). When carnosine (3 mM) or hydralazine (0.2 mM) was supplemented in the medium, all of the PCD-associated events caused by H 2 O 2 and NaCl were largely suppressed.…”

NO and H2O2 contribute to SO2 toxicity via Ca2+ signaling in Vicia faba guard cells

“…Hydrogen peroxide (H 2 O 2 ) and NO, which function both synergistically and independently, have been established as ubiquitous signal transduction components to mediate various biological processes, including defense-related gene expression, stomatal closure, and programmed cell death (PCD) (Hausladen and Stamler 1998;Yamasaki and Sakihama 2000;Neill et al 2002;Brüne 2003;Mori and Schroeder 2004;De Pinto et al 2006;Reape and McCabe 2008;Shao et al 2008;Besson-Bard et al 2009;González et al 2012; Responsible editor: Yi-ping Chen Electronic supplementary material The online version of this article (doi:10.1007/s11356-017-8612-6) contains supplementary material, which is available to authorized users. Felicitas et al 2013).…”