Genome-wide analysis of high-altitude maize and gene knockdown stocks implicates chromatin remodeling proteins in response to UV-B
A comparative analysis, by expression profiling of maize, was performed to identify novel components in the mechanisms of maize responses to UV-B. Five high-altitude landraces grown from 2000 to 3400 m naturally receive higher UV-B fluence than plants at lower altitudes and similar latitudes. These high-altitude landraces were compared directly with a low-altitude line and with literature reports for other temperate maize lines. A microarray analysis demonstrated that among the UV-B responsive transcripts, several types of gene implicated in chromatin remodeling are differentially expressed before and after UV-B treatment in high-altitude lines. RNAi transgenic plants with lower expression of four such chromatin-associated genes exhibited hypersensitivity to UV-B by measurements of leaf arching, increased leaf chlorosis and necrosis, and altered UV-B regulation of selected genes. These results collectively suggest that genes involved in chromatin remodeling are crucial for UV-B acclimation and that some high-altitude lines exhibit adaptations to this challenge.
Document Type: Research Article
Affiliations: 1: Departments of Biology and Marine Biology, and 2: Mathematics and Applied Statistics, University of North Carolina at Wilmington, 601 S. College Rd, Wilmington, NC 28403, USA 3: Department of Biological Sciences, Stanford University, 385 Serra Mall, Stanford, CA 94305-5020, USA,
Publication date: May 1, 2006