Mechanisms of flowering time control by the novel flowering time genes GNC and GNL
This project aims at understanding how flowering is controlled by gibberellin (GA) and cold temperature and how flowering time control is linked to frost tolerance. This is based on our finding that transcription factors of the GNÜLLER family, notably the GA-regulated genes GNC and GNL, delay flowering and at the same time confer frost tolerance in Arabidopsis thaliana. We also observed that GNC/GNL expression is activated by FLC in response to intermittent cold temperatures that delay flowering and that GNC/GNL expression confers frost tolerance by activating cold-responsive gene expression. Using molecular and genetic approaches we now want to examine (1) how GNC/GNL integrate GA- and FLC-dependent signals to control flowering time, (2) whether expression differences of GNC/GNL can explain differences in flowering and frost tolerance in 5 selected Arabidopsis accessions, and (3) whether and how GNC/GNL control flowering time and frost tolerance in crop species. Understanding how GA signalling, flowering time and frost tolerance are controlled and how these signalling pathways are interconnected may allow to accelerate breeding of frost tolerance, a desirable but difficult-to-assess trait, and flowering time, an easy-to-assess trait, in the context of knowledge-based breeding programs.
Project related publications:
Lutz U,Posé D, Pfeifer M, Gundlach H, Hagmann J, Wang C, Weigel D, Mayer KFX, Schmid M, Schwechheimer C (2015). Modulation of Ambient Temperature-Dependent Flowering in Arabidopsis thaliana by Natural Variation of FLOWERING LOCUS M. PLoS Genet 11(10):e1005588. doi:10.1371/journal.pgen.1005588
Lutz U,Posé D, Pfeifer M, Gundlach H, Hagmann J, Wang C, Weigel D, Mayer KFX, Schmid M, Schwechheimer C (2015). Modulation of Ambient Temperature-Dependent Flowering in Arabidopsis thaliana by Natural Variation of FLOWERING LOCUS M. PLoS Genet 11(10):e1005588. doi:10.1371/journal.pgen.1005588Behringer C, Bastakis E, Ranftl Q, Mayer KFX, Schwechheimer C (2014). Functional diversification within the family of B-GATA transcription factors through the LLM-domain. Plant Physiology, pp.114.246660, doi: http://dx.doi.org/10.1104/pp.114.246660
Richter R, Bastakis E, Schwechheimer C (2013). Cross-repressive interactions between SOC1 and the GATAs GNC and GNL/CGA1 in the control of greening, cold tolerance and flowering time in Arabidopsis. Plant Physiology, doi:10.1104/pp.113.219238
Richter R, Behringer C, Zourelidou M, and Schwechheimer C (2013). Convergence of auxin and gibberellin signaling on the regulation of the GATA transcription factors GNC and GNL in Arabidopsis thaliana. Proceedings of the National Academy of Sciences of the United States of America, doi: 10.1073/pnas.1304250110