PhD Defence by Ulla Dolde – University of Copenhagen

Plant and Environmental Sciences > Events > PhD Defence by Ulla Dolde

PhD Defence by Ulla Dolde

MicroProteins are small, single-domain proteins that act by dimerization with larger multi-domain proteins and can prevent them from forming functional complexes. To dates 22 microProteins have been identified in plants that regulate their targets by sequestering them into non-productive complexes. The two orthologues microProteins, miP1a and miP1b were identified using a computational analysis. MiP1a and miP1b are small B-Box containing proteins that change the biological activity of CONSANS (CO), a major regulator of flowering in Arabidopsis thaliana. They are known to be the first microProteins that regulate their target by forming a high-order complex. They form a trimeric complex with CO and the transcriptional repressor TOPLESS (TPL) which converts CO into a floral repressor.

Currently all identified and characterized microProteins regulate transcription factors. Using a computational approach novel microProtein candidates were identified in several sequenced genomes that may affect complex formation of a wider range of multi-domain proteins. In Arabidopsis thaliana conserved putative microProteins were identified and classified into protein classes dependent on their putative ancestor and protein-protein-interaction (PPI) domain. Using a synthetic microProtein approach, we demonstrate that microProteins are able to regulate multi-domain proteins belonging to different protein classes. Furthermore, these results revealed that microProteins may provide a use full tool for post-translational regulation in plant due to their function in protein regulation. 

Associate Professor Stephan Wenkel

Assessment committee
Research Group Leader Sabine Müller, University of Tübingen, Germany
Associate Professor Fabio Fornara, University of Milan, Italy
Professor Poul Erik Jensen (chair)

Reception after the defence in the CPSC hall