Cytokinin as a regulator of chloroplast development and function
Final Report Abstract
We have described in detail the role of cytokinin in regulating the etioplast-to-chloroplast transition. This work in the context of the de-etiolation (skotomorphogenesis) has led to a study, in collaboration with Dr. Henrik Johansson, on the role of cytokinin in regulating hypocotyl elongation. In a major invited review we have summarized current knowledge of the role of role of cytokinin in chloroplast development. In a second project part we have described a novel protective function of cytokinin in the light stress response. From the analysis of the light stress response has emerged a new project describing a novel type of abiotic stress reducing the photosynthetic capacity of Arabidopsis leaves and eventually causing cell deatch. Dr. Anne Cortleven, who had been the postdoctoral fellow of this project, has contributed with her expertise on plastid development and photosynthesis also to work about an F-box protein of Arabidopsis which has an impact on plastid development. The parts of the project, which were not prioritized or not successful are the study of the plastids' own cytokinin metabolism and the establishment of a genetic screen in order to identify genes relevant for cytokinin action on plastid development.
Publications
- (2014) A novel protective function for cytokinin in the light stress response is mediated by the AHK2 and AHK3 receptors. Plant Physiology 164, 1470-1483
Cortleven A., Nitschke S., Klaumünzer M., AbdElgawad H., Asard H., Grimm B., Riefler M., Schmülling T.
(See online at https://doi.org/10.1104/pp.113.224667) - (2015) Regulation of chloroplast development and function: a long-known cytokinin function reassessed. Journal of Experimental Botany 66, 4999-5013
Cortleven A. and Schmülling T.
(See online at https://doi.org/10.1093/jxb/erv132) - (2016) Circadian stress in cytokinin-deficient plants: changing the light-dark regime affects the circadian clock and causes jasmonic acid-dependent cell death. Plant Cell 28, 1616-1639
Nitschke S., Cortleven A., Iven T., Feussner I, Havaux M., Riefler M., Schmülling T.
(See online at https://doi.org/10.1105/tpc.16.00016) - (2016) Cytokinin regulates the etioplast-chloroplast transition through the two-component signaling system and activation of chloroplast-related genes. Plant Physiology 172, 464-478
Cortleven, A., Marg, I., Yamburenko, M.V., Schlicke, H., Hill, K., Grimm, B., Schaller, E.G., Schmülling, T.
(See online at https://doi.org/10.1104/pp.16.00640) - (2017) Analysis of CFB, a cytokinin-responsive gene of Arabidopsis thaliana encoding a novel F-box protein regulating sterol biosynthesis. Journal of Experimental Botany 68, 2769-2785
Brenner, W.G., Leuendorf, J.E., Cortleven, A., Schmülling, T.
(See online at https://doi.org/10.1093/jxb/erx146) - (2017) Novel stress in plants by altering the photoperiod. Trends in Plant Science 22, 913-916
Nitschke, S., Cortleven, A., Schmülling, T.
(See online at https://doi.org/10.1016/j.tplants.2017.09.005)