Send to

Choose Destination
Plant Cell Environ. 2018 Aug;41(8):1727-1738. doi: 10.1111/pce.13332. Epub 2018 Jun 8.

Singlet oxygen-triggered chloroplast-to-nucleus retrograde signalling pathways: An emerging perspective.

Author information

Shanghai Center for Plant Stress Biology and Center of Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
Department of Molecular Biology and Plant Biology, University of Geneva, 1205, Geneva, Switzerland.


Singlet oxygen (1 O2 ) is a prime cause of photo-damage of the photosynthetic apparatus. The chlorophyll molecules in the photosystem II reaction center and in the light-harvesting antenna complex are major sources of 1 O2 generation. It has been thought that the generation of 1 O2 mainly takes place in the appressed regions of the thylakoid membranes, namely, the grana core, where most of the active photosystem II complexes are localized. Apart from being a toxic molecule, new evidence suggests that 1 O2 significantly contributes to chloroplast-to-nucleus retrograde signalling that primes acclimation and cell death responses. Interestingly, recent studies reveal that chloroplasts operate two distinct 1 O2 -triggered retrograde signalling pathways in which β-carotene and a nuclear-encoded chloroplast protein EXECUTER1 play essential roles as signalling mediators. The coexistence of these mediators raises several questions: their crosstalk, source(s) of 1 O2 , downstream signalling components, and the perception and reaction mechanism of these mediators towards 1 O2 . In this review, we mainly discuss the molecular genetic basis of the mode of action of these two putative 1 O2 sensors and their corresponding retrograde signalling pathways. In addition, we also propose the possible existence of an alternative source of 1 O2 , which is spatially and functionally separated from the grana core.


EXECUTER1; acclimation; photoinhibition; programmed cell death; retrograde signalling; singlet oxygen; β-carotene


Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center