title: Analysis of gene expression profiles of two near-isogenic lines differing at a QTL region affecting oil content at high temperatures during seed maturation in oilseed rape (Brassica napus L.).
abstract: Seed oil production in oilseed rape is greatly affected by the temperature during seed maturation. However, the molecular mechanism of the interaction between genotype and temperature in seed maturation remains largely unknown. We developed two near-isogenic lines (NIL-9 and NIL-1), differing mainly at a QTL region influencing oil content on Brassica napus chromosome C2 (qOC.C2.2) under high temperature during seed maturation. The NILs were treated under different temperatures in a growth chamber after flowering. RNA from developing seeds was extracted on the 25th day after flowering (DAF), and transcriptomes were determined by microarray analysis. Statistical analysis indicated that genotype, temperature, and the interaction between genotype and temperature (G × T) all significantly affected the expression of the genes in the 25 DAF seeds, resulting in 4,982, 19,111, and 839 differentially expressed unisequences, respectively. NIL-9 had higher seed oil content than NIL-1 under all of the temperatures in the experiments, especially at high temperatures. A total of 39 genes, among which six are located at qOC.C2.2, were differentially expressed among the NILs regardless of temperature, indicating the core genetic divergence that was unaffected by temperature. Increasing the temperature caused a reduction in seed oil content that was accompanied by the downregulation of a number of genes associated with red light response, photosynthesis, response to gibberellic acid stimulus, and translational elongation, as well as several genes of importance in the lipid metabolism pathway. These results contribute to our knowledge of the molecular nature of QTLs and the interaction between genotype and temperature.
authors: College of Agriculture and Biotechnology, Zhejiang University, 866 Yu-Hang-Tang Road, Hangzhou, 310058, People's Republic of China.
authors: Yana
authors: Y
authors: Zhu
authors: Zhengying
authors: Z
authors: Cao
authors: Fei
authors: F
authors: Xu
authors: Yi
authors: Y
authors: Huang
authors: Mingxun
authors: M
authors: Chen
authors: Wanli
authors: W
authors: Guo
authors: Weijun
authors: W
authors: Zhou
authors: Jun
authors: J
authors: Zhu
authors: Jinling
authors: J
authors: Meng
authors: Jitao
authors: J
authors: Zou
authors: Lixi
authors: L
authors: Jiang
mesh_terms: D029688:Brassica napus / Q000737:chemistry / Q000235:genetics*; D002874:Chromosome Mapping; D017931:DNA Primers / Q000235:genetics; D005227:Fatty Acids / Q000032:analysis; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D005838:Genotype; D006358:Hot Temperature; D046228:Microarray Analysis; D010938:Plant Oils / Q000032:analysis*; D040641:Quantitative Trait Loci / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D017931:DNA Primers; D005227:Fatty Acids; D010938:Plant Oils