WHIRLY1 in barley was isolated as a potential regulator of the senescence-associated gene HvS40. In order to investigate whether the plastid-nucleus-located DNA/RNA-binding protein WHIRLY1 plays a role in regulation of leaf senescence, primary foliage leaves from transgenic barley plants with an RNAi-mediated knockdown of the WHIRLY1 gene were characterized by typical senescence parameters, namely pigment contents, function and composition of the photosynthetic apparatus, as well as expression of selected genes known to be either down- or up-regulated during leaf senescence. When the plants were grown at low light intensity, senescence progression was similar between wild-type and RNAi-W1 plants. Likewise, dark-induced senescence of detached leaves was not affected by reduction of WHIRLY1. When plants were grown at high light intensity, however, senescence was induced prematurely in wildtype plants but was delayed in RNAi-W1 plants. This result suggests that WHIRLY1 plays a role in light sensing and/or stress communication between chloroplasts and the nucleus.
Bibliographical noteFunding Information:
We acknowledge the excellent technical assistance of Susanne Braun and Ulrike Voigt (Institute of Botany, CAU Kiel, Germany). Hartmut Kaiser is thanked for the setting up of gas exchange measurements. We also acknowledge the initial investigations performed by Dr Elzbieta Golemic. We thank Poul-Erik Jensen, University of Copenhagen, Denmark, for providing the antibody directed towards photosystem I proteins. WK was supported by the European Marie Curie Initial Training Network 'CropLife'. KK and AD acknowledge support from the German-Israeli Foundation for Scientific Research and Development (GIF) grant no. I-1212-315.13.
© The Author 2017.
- Chloroplast proteins
- DNA/RNA-binding protein WHIRLY1
- High light
- Leaf senescence
ASJC Scopus subject areas
- Plant Science