Molecular mapping of Arabidopsis thaliana lipid-related orthologous genes in Brassica napus

Abstract

Quantitative Trait Loci (QTL) for oil content has been previously analyzed in a SG-DH population from a cross between a Chinese cultivar and a European cultivar of Brassica napus. Eight QTL with additive and epistatic effects, and with environmental interactions were evaluated. Here we present an integrated linkage map of this population predominantly based on informative markers derived from Brassica sequences, including 249 orthologous A. thaliana genes, where nearly half (112) are acyl lipid metabolism related genes. Comparative genomic analysis between B. napus and A. thaliana revealed 33 colinearity regions. Each of the conserved A. thaliana segments is present two to six times in the B. napus genome. Approximately half of the mapped lipid-related orthologous gene loci (76/137) were assigned in these conserved colinearity regions. QTL analysis for seed oil content was performed using the new map and phenotypic data from 11 different field trials. Nine significant QTL were identified on linkage groups A1, A5, A7, A9, C2, C3, C6 and C8, together explaining 57.79% of the total phenotypic variation. A total of 14 lipid related candidate gene loci were located in the confidence intervals of six of these QTL, of which ten were assigned in the conserved colinearity regions and felled in the most frequently overlapped QTL intervals. The information obtained from this study demonstrates the potential role of the suggested candidate genes in rapeseed kernel oil accumulation.

Identification of QTL for seed coat colour and oil content inBrassica napusby association mapping using SSR markers

“…associated with oil content, distributed on A1 and A8 in the RIL population (Yan et al 2009b), and were regarded as the same loci for oil content (Delourme et al 2006;Qiu et al 2006;Zhao et al 2012;Chen et al 2013;Jiang et al 2014). Hence, the association mapping results were in good agreement with published QTL detected in other B. napus populations.…”

“…These works showed that seed oil content is quantitative in nature and controlled by multiple genes termed quantitative trait loci (QTL), found in almost all the 19 linkage groups, and the trait is affected by environment (G )E) (Burns et al 2003;Zhao et al 2005Zhao et al , 2006Delourme et al 2006;Qiu et al 2006;Amar et al 2008;Yan et al 2009b;Chen et al 2010Chen et al , 2013Sun et al 2012). Moreover, a QTL associated with oil content located in the linkage group 1 (A1) near the public SSR markers BRAS041 or BRAS078 of B. napus has been frequently reported (Zhao et al 2005(Zhao et al , 2012Delourme et al 2006;Qiu et al 2006;Chen et al 2013;Jiang et al 2014), and we also found CB10369 and BRAS041 were mapped to the adjacent regions. Similarly, it should also be mentioned that one QTL for seed oil content was mapped to linkage group A8 in different crosses (Burns et al 2003;Delourme et al 2006;Qiu et al 2006;Amar et al 2008).…”

Genetic analysis and fine mapping of the LOBED-LEAF 1 (BnLL1) gene in rapeseed (Brassica napus L.)

“…The two parents (Yuye 87 and Zheyou 50) and six bulks were used for bulked segregant analysis (Michelmore et al 1991) to identify markers linked to the BnLL1 gene. Two hundred and four markers, covering all 19 linkage groups, were selected from B. napus genetic map (SG map) based on a doubledhaploid population derived from Sollux 9 Gaoyou (Zhao et al 2012), and screened in two parents and DNA bulks. The markers showing polymorphism between lobed-leaf bulks and entire-leaf bulks were confirmed in population A1.…”

Identification of quantitative trait loci associated with oil content and development of near isogenic lines for stableqOC-A10inBrasscia napusL.

“…Recently, some studies have used parental lines with significant differences in oil content (>10%) (Sun et al 2012;Wang et al 2013), which was useful to detect QTL. These studies showed that QTL for oil content were distributed on 18 of 19 B. napus chromosomes, except chromosome C4 (Ecke et al 1995;Zhao et al 2005Zhao et al , 2006Zhao et al , 2008Zhao et al , 2012Delourme et al 2006;Qiu et al 2006;Sun et al 2012;Wang et al 2013;Jiang et al 2014). The number of QTL detected varied from three (Ecke et al 1995) to 27 (Chen et al 2010) and explained phenotypic variation ranging from 1.2% (Delourme et al 2006) to more than 20% (Chen et al 2010;Sun et al 2012).…”

“…Some efforts have been made in quantitative trait loci (QTL) mapping for oil content in rapeseed (Ecke et al 1995;Burns et al 2003;Zhao et al 2005Zhao et al , 2006Zhao et al , 2008Zhao et al , 2012Delourme et al 2006;Qiu et al 2006;Sun et al 2012;Wang et al 2013;Jiang et al 2014) that shed light on dissecting the genetic mechanism of oil content and provide a theoretical basis to develop effective breeding methods. Most of this research has been carried out using doubled haploid (DH) populations, including DY ('Darmor-bzh' × 'Yudal') and RNSL ('Rapid' × 'NSL96/25') (Delourme et al 2006), TN ('Tapidor' × 'Ningyou7') (Qiu et al 2006;Jiang et al 2014), SG ('Sollux' × 'Gaoyou') (Zhao et al 2005(Zhao et al , 2006(Zhao et al , 2008(Zhao et al , 2012, Z5 ('ZY036' × '51070') (Sun et al 2012), and KN ('KenC-8' × 'N53-2') populations. Meanwhile, only a few studies based on recombinant inbred line (RIL) population ) and intervarietal subsets of substitution lines (Burns et al 2003) have been performed.…”