Biologische Funktion eines Organell-lokalisierten Mitglieds der Cryptochrom/Photolyase Familie und chemische Schaltung von Photorezeptoren
Final Report Abstract
In this project the formation of cry1 and cry2 dimers in Arabidopsis was analyzed. CoIP studies showed that cry1 and cry2 form homodimers. Heterodimerization between cry1 and cry2 was not detected. Furthermore, it was investigated whether rapamycin/rapalogmediated dimerization of the C-termini of cry1 (CCT1) and cry2 (CCT2) leads to the induction of processes in darkness that are otherwise initiated by blue light and cryptochromes. Results from these studies showed indeed rapalog-induced expression of light-controlled target genes in darkness. However, initiation of flowering under short-day conditions upon CCT2-dimerization was not observed. Therefore, it is likely that cryptochromes regulate only a subset of their targets via the C-terminal extensions. The cry2-mediated flowering response seems to depend on the N- terminal photosensory domain, which interacts with the regulatory proteins CIB1 and SPA1. Results from collaboration with Lars Hennig (ETH Zürich) showed however, that cry1 is likewise able to induce flowering.
Publications
- (2008) Chemically induced and light-independent cryptochrome photoreceptor activation. Molecular Plant 1, 4-14
Rosenfeldt G., Muñoz Viana R., von Arnim A.G., Mootz H.D., Batschauer A.
- (2010) A gain-of-function mutation of Arabidopsis CRYPTOCHROME 1 promotes flowering. Plant Physiol. 154, 1633-1645
Exner V., Alexandre C., Rosenfeldt G., Alfarano P., Nater M., Caflisch A., Gruissem W., Batschauer A., Hennig L.
