Identification of mutants of Arabidopsis defective in acclimation of photosynthesis to the light environment.
In common with many other higher plant species, Arabidopsis undergoes photosynthetic acclimation, altering the composition of the photosynthetic apparatus in response to fluctuations in its growth environment. The changes in photosynthetic function that result from acclimation can be detected in a noninvasive manner by monitoring chlorophyll (Chl) fluorescence. This technique has been used to develop a screen that enables the rapid identification of plants defective at ACCLIMATION OF PHOTOSYNTHESIS TO THE ENVIRONMENT (APE) loci. The application of this screen to a population of T-DNA-transformed Arabidopsis has successfully led to the identification of a number of mutant lines with altered Chl fluorescence characteristics. Analysis of photosynthesis and pigment composition in leaves from three such mutants showed that they had altered acclimation responses to the growth light environment, each having a distinct acclimation-defective phenotype, demonstrating that screening for mutants using Chl fluorescence is a viable strategy for the investigation of acclimation. Sequencing of the genomic DNA flanking the T-DNA elements showed that in the ape1 mutant, a gene was disrupted that encodes a protein of unknown function but that appears to be specific to photosynthetic organisms, whereas the ape2 mutant carries an insertion in the region of the TPT gene encoding the chloroplast inner envelope triose phosphate/phosphate translocator.
Walters
Robin G
RG
Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom.
Shephard
Freya
F
Rogers
Jennifer J M
JJ
Rolfe
Stephen A
SA
Horton
Peter
P
D000064:Acclimatization / Q000502:physiology* / Q000528:radiation effects; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000528:radiation effects; D001483:Base Sequence; D002245:Carbon Dioxide / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism / Q000528:radiation effects; D008027:Light; D045342:Light-Harvesting Protein Complexes; D008969:Molecular Sequence Data; D009154:Mutation; D010100:Oxygen / Q000378:metabolism; D010788:Photosynthesis / Q000502:physiology* / Q000528:radiation effects; D045322:Photosynthetic Reaction Center Complex Proteins / Q000378:metabolism / Q000528:radiation effects; D020524:Thylakoids / Q000378:metabolism / Q000528:radiation effects
D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D002734:Chlorophyll; D002245:Carbon Dioxide; D010100:Oxygen