title: Boechera species exhibit species-specific responses to combined heat and high light stress.
abstract: As sessile organisms, plants must be able to complete their life cycle in place and therefore tolerance to abiotic stress has had a major role in shaping biogeographical patterns. However, much of what we know about plant tolerance to abiotic stresses is based on studies of just a few plant species, most notably the model species Arabidopsis thaliana. In this study we examine natural variation in the stress responses of five diverse Boechera (Brassicaceae) species. Boechera plants were exposed to basal and acquired combined heat and high light stress. Plant response to these stresses was evaluated based on chlorophyll fluorescence measurements, induction of leaf chlorosis, and gene expression. Many of the Boechera species were more tolerant to heat and high light stress than A. thaliana. Gene expression data indicates that two important marker genes for stress responses: APX2 (Ascorbate peroxidase 2) and HsfA2 (Heat shock transcription factor A2) have distinct species-specific expression patterns. The findings of species-specific responses and tolerance to stress indicate that stress pathways are evolutionarily labile even among closely related species.
authors.affiliation: Dept. of Biology San Diego State University, San Diego, California, United States of America.
authors.forename: Genna
authors.initials: G
authors.lastname: Gallas
authors.affiliation: Dept. of Biology San Diego State University, San Diego, California, United States of America.
authors.forename: Elizabeth R
authors.initials: ER
authors.lastname: Waters
mesh_terms: D017360:Arabidopsis / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics; D019607:Brassicaceae / Q000145:classification* / Q000502:physiology*; D002734:Chlorophyll / Q000737:chemistry; D005453:Fluorescence; D018506:Gene Expression Regulation, Plant; D018869:Heat-Shock Response; D006358:Hot Temperature; D008027:Light; D018515:Plant Leaves / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics; D013045:Species Specificity; D013312:Stress, Physiological
chemical_list: D029681:Arabidopsis Proteins; D010940:Plant Proteins; D002734:Chlorophyll