RUL1 to RUL3:Characterization of three novel genes from Arabidopsis thaliana

• Applicant: Professor Dr. Norbert Sauer
• Subject Area: Plant Physiology
• Term: from 2010 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 168147811

In a mutant screen for altered symplastic connectivity, a gene (RUG8) was identified that encodes a previously uncharacterized “protein of unknown function”. We showed that this protein is most likely a novel transcription factor that affects Arabidopsis root development, including the formation of the quiescent center, cellular maturation and radial patterning - but also the symplastic connectivity between root cells. The present proposal focuses on the characterization of three RUG8-like genes, RUL1 to RUL3 that show significant structural and sequence homologies to RUG8. Like RUG8, these genes encode previously uncharacterized proteins. All three RUL3 cDNAs and promoters were cloned, and preliminary analyses of available mutant lines were performed. As RUG8, RUL2 and RUL3 are nuclear localized, and first analyses of a rul3 mutant revealed phenotypic alterations (reduced unloading of GFP from the phloem and altered root development) that are similar to those found in rug8 mutants. The aim of the present project is the functional and physiological characterization of RUL1, RUL2 and RUL3.

• DFG Programme: Research Grants