title: Nucleotide variation in the NCED3 region of Arabidopsis thaliana and its association study with abscisic acid content under drought stress.
abstract: Drought tolerance is a comprehensive quantitative trait that is being understood further at the molecular genetic level. Abscisic acid (ABA) is the main drought-induced hormone that regulates the expression of many genes related to drought responses. 9-cis-epoxycarotenoid dioxygenase (NCED3) is thought to be a key enzyme in ABA biosynthesis. In this paper, we measured the ABA content increase under drought stress, and sequenced and compared the sequence of AtNCED3 among 22 Arabidopsis thaliana accessions. The results showed that the fold of ABA content increase under drought stress was highly variable among these accessions. High density single nucleotide polymorphism (SNP) and insertion/deletion (indel) were found in the AtNCED3 region, on average one SNP per 87.4 bp and one indel per 502 bp. Nucleotide diversity was significantly lower in the coding region than that in non-coding regions. The results of an association study with anova analysis suggested that the 274th site (P<-->S) and the 327th site (P<-->R) amino acid variations might be the cause of ABA content increase of 163av accession under drought stress.
authors.affiliation: Beijing Agro-Biotechnology Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
authors.forename: Gang-Ping
authors.initials: GP
authors.lastname: Hao
authors.forename: Xiu-Hai
authors.initials: XH
authors.lastname: Zhang
authors.forename: Yong-Qin
authors.initials: YQ
authors.lastname: Wang
authors.forename: Zhong-Yi
authors.initials: ZY
authors.lastname: Wu
authors.forename: Cong-Lin
authors.initials: CL
authors.lastname: Huang
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics*; D018744:DNA, Plant / Q000235:genetics; D049308:Dioxygenases; D055864:Droughts; D016366:Open Reading Frames; D010105:Oxygenases / Q000235:genetics*; D010940:Plant Proteins; D011110:Polymorphism, Genetic; D017422:Sequence Analysis, DNA; D013312:Stress, Physiological; D014867:Water / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D018744:DNA, Plant; D010940:Plant Proteins; D014867:Water; D000040:Abscisic Acid; D010105:Oxygenases; D049308:Dioxygenases; C109043:9-cis-epoxy-carotenoid dioxygenase