title: Spontaneously occurring mutations in the cyclobutane pyrimidine dimer photolyase gene cause different sensitivities to ultraviolet-B in rice.
abstract: Sensitivity to ultraviolet-B (UVB) radiation (280-320 nm) varies widely among rice cultivars. We previously indicated that UV-resistant rice cultivars are better able to repair cyclobutane pyrimidine dimers (CPDs) through photorepair than are UV-sensitive cultivars. In this paper, we report that UVB sensitivity in rice, in part, is the result of defective CPD photolyase alleles. Surjamkhi (indica) exhibited greater sensitivity to UVB radiation and was more deficient in CPD photorepair ability compared with UV-resistant Sasanishiki (japonica). The deficiency in CPD photorepair in Surjamkhi resulted from changes in two nucleotides at positions 377 and 888 in the photolyase gene, causing alterations of two deduced amino acids at positions 126 and 296 in the photolyase enzyme. A linkage analysis in populations derived from Surjamkhi and Sasanishiki showed that UVB sensitivity is a quantitative inherited trait and that the CPD photolyase locus is tightly linked with a quantitative trait locus that explains a major portion of the genetic variation for this trait. These results suggest that spontaneously occurring mutations in the CPD photolyase gene cause different degrees of sensitivity to UVB in rice, and that the resistance of rice to UVB radiation could be increased by increasing the photolyase function through conventional breeding or bioengineering.
authors.affiliation: Department of Environmental Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan. j-hidema@ige.tohoku.ac.jp
authors.forename: Jun
authors.initials: J
authors.lastname: Hidema
authors.forename: Mika
authors.initials: M
authors.lastname: Teranishi
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Iwamatsu
authors.forename: Tokuhisa
authors.initials: T
authors.lastname: Hirouchi
authors.forename: Tadamasa
authors.initials: T
authors.lastname: Ueda
authors.forename: Tadashi
authors.initials: T
authors.lastname: Sato
authors.forename: Benjamin
authors.initials: B
authors.lastname: Burr
authors.forename: Betsy M
authors.initials: BM
authors.lastname: Sutherland
authors.forename: Kazuo
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kumagai
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D003433:Crosses, Genetic; D004260:DNA Repair; D018744:DNA, Plant; D004255:Deoxyribodipyrimidine Photo-Lyase / Q000235:genetics* / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D008040:Genetic Linkage; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000528:radiation effects*; D011740:Pyrimidine Dimers / Q000378:metabolism*; D040641:Quantitative Trait Loci; D017386:Sequence Homology, Amino Acid; D014466:Ultraviolet Rays
chemical_list: D018744:DNA, Plant; D011740:Pyrimidine Dimers; D004255:Deoxyribodipyrimidine Photo-Lyase