Poster: Photosynthesis

Abs # 362: Acclimation of photosynthesis to irradiance in Arabidopsis thaliana

Presenter:	Howard, Caroline A., mbp00cah@sheffield.ac.uk
Authors	Howard, Caroline A. (A)   Horton, Peter  (A)   Gray, Julie E. (A)   Walters, Robin G. (B)
Affiliations:	(A): Molecular Biology and Biotechnology, University of Sheffield (B): Plant Sciences, University of Oxford

Plants have developed a range of mechanisms to optimise their photosynthetic responses to different light environments. Acclimation involves the optimisation of leaf structure and organelle content, specifically involving alterations in the function and composition of the chloroplast. The aim of this project is to understand the way in which acclimation is regulated, uncovering the genes and proteins involved. Two different approaches have been taken, in the first we have attempted to exploit the vast resource of untapped genetic variation in the large number of geographically distinct Arabidopsis thaliana accessions which are available. We have characterised in detail the acclimation responses of a number of A. thaliana accessions to growth under a range of light intensities from 1000 µmol quanta.m^-2.s^-1 to 35 µmol quanta.m^-2.s^-1. There are marked variations in the extent and nature of the acclimation response which will be discussed. These studies will inform future QTL approaches to the investigation of acclimation. Secondly we have adopted a transcriptomics approach in association with the GARNet Affymetrix microarray project at NASC (Nottingham Arabidopsis Stock Centre, University of Nottingham). Analysis of changes in gene expression in the Ws-2 accession following a transfer from low light (100 µmol quanta.m^-2.s^-1) to high light (400 µmol quanta.m^-2.s^-1) or vice versa will be presented.