Exploiting Next Generation Sequencing to identify key-players in Arabiodopsis thaliana hypocotyl expansion.

This project aims to increase our knowledge on the regulation of plant cell elongation, as it shapes plant size and form and determines primary biomass production. Arabidopsis thaliana will serve as model plant and the hypocotyl will be used to identify key-players in the regulation of (cell) elongation.The hypocotyl's elongation is very prominent in the dark, but upon perception of light, elongation is rapidly inhibited. We have identified and phenotyped a unique mutant, apollo, that fails to inhibit elongation in the light, but that shows all other signs of de-etiolation.In order to identify genes and miRNAs with a crucial role in the light-regulation of cell elongation we will compare the transcriptome of 1) dark-grown wild-type with dark-grown apollo, 2) light-grown wild-type with light-grown apollo and 3) dark-grown wild-type but transfered to light with dark- grown apollo but also transfered to light using Next Generation Sequencing (NGS).In addition, the mutant results in the sustained up-regulation of a transcription factor (ORPHEUS) that in wild-type seedlings is down-regulated upon light preception, identifying it as a potential switch to regulate expansion and inhibition of expansion. Therefore, we will identify the target genes of this transcription factor using NGS on DNA that results from chromatin immunoprecipitation. A functional analysis with a reverse genetic approach will link the individual genes to their function and role in the expansion-regulation.

Keywords:CELL ELONGATION, NEXT GENERATION SEQUENCING, PLANT GROWTH REGULATION, ARABIDOPSIS THALIANA L.

Disciplines:General biology, Plant biology