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 2,000 to 3,400 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.
Casati
Paula
P
Department of Biological Sciences, Stanford University, 385 Serra Mall, Stanford, CA 94305-5020, USA. pcasati@fbioyf.unr.edu.ar
Stapleton
Ann E
AE
Blum
James E
JE
Walbot
Virginia
V
D000222:Adaptation, Physiological; D042002:Chromatin Assembly and Disassembly / Q000235:genetics*; D016000:Cluster Analysis; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D020411:Oligonucleotide Array Sequence Analysis; D018515:Plant Leaves / Q000033:anatomy & histology / Q000378:metabolism / Q000528:radiation effects; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D030821:Plants, Genetically Modified / Q000378:metabolism / Q000528:radiation effects; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D014466:Ultraviolet Rays; D003313:Zea mays / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects*
D009687:Nuclear Proteins; D010940:Plant Proteins; D012333:RNA, Messenger