Differential sulphur assimilation mechanism regulates response of Arabidopsis thaliana natural variation towards arsenic stress under limiting sulphur condition.
Arsenic (As) is a ubiquitous element, which imposes threat to crops productivity and human health through contaminated food chain. As a part of detoxification mechanism, As is chelated and sequestered into the vacuoles via sulphur containing compounds glutathione (GSH) and phytochelatins (PCs). Under limiting sulphur (LS) conditions, exposure of As leads to enhanced toxic effects in plants. Therefore, it is a prerequisite to understand molecular mechanisms involved in As stress response under sulphur deficiency conditions in plants. In recent years, natural variation has been utilized to explore the genetic determinants linked to plant development and stress response. In this study, natural variation in Arabidopsis has been utilized to understand the molecular mechanisms underlying LS and As(III) stress response. Analysis of different accession of Arabidopsis led to the identification of Koz2-2 and Ri-0 as the most tolerant and sensitive accessions, respectively, towards As(III) and LS+As(III) stress. Biochemical analysis and expression profiling of the genes responsible for sulphur transport and assimilation as well as metal detoxification and accumulation revealed significantly enhanced sulphur assimilation mechanism in Koz2-2 as compared to Ri-0. Analyses suggest that genetic variation regulates differential response of accessions towards As(III) under LS condition.
['Khare|Ria|R|', 'Kumar|Smita|S|', 'Shukla|Tapsi|T|', 'Ranjan|Avriti|A|', 'Trivedi|Prabodh Kumar|PK|']
D000222:Adaptation, Physiological D027321:Anion Transport Proteins D017360:Arabidopsis D029681:Arabidopsis Proteins D001151:Arsenic D020869:Gene Expression Profiling D017343:Genes, Plant D014644:Genetic Variation D005978:Glutathione D018384:Oxidative Stress D054811:Phytochelatins D013312:Stress, Physiological D013455:Sulfur
Arabidopsis Natural variation Arsenic Detoxification Accumulation Sulphur homeostasis