Genetic Control of Storage Oil Synthesis in Seeds of Arabidopsis

Abstract

Quantitative trait loci (QTL) that control seed oil content and fatty acid composition were studied using a recombinant inbred population derived from a cross between the Arabidopsis ecotypes Landsberg erecta and Cape Verdi Islands. Multiple QTL model mapping identified two major and two minor QTL that account for 43% of the variation in oil content in the population. The most significant QTL is at the bottom of chromosome 2 and accounts for 17% of the genetic variation. Two other significant QTL, located on the upper and lower arms of chromosome 1, account for a further 19% of the genetic variation. A QTL near to the top of chomosome 3 is epistatic to that on the upper arm of chromosome 1. There are strong QTL for linoleic (18:2) and linolenic (18:3) acids contents that colocate with the FAD3 locus, another for oleic acid (18:1) that colocates with FAD2 and other less significant QTL for palmitic (16:0), stearic (18:0), and eicosaenoic (20:1) acids. The presence of the QTL for seed oil content on chromosome 2 was confirmed by the generation of lines that contain a 22-cM region of Landsberg erecta DNA at the bottom of chromosome 2 in a background containing Cape Verdi Islands in other regions of the genome that had been shown to influence oil content in the QTL analysis.

Genome Wide Analysis of Fatty Acid Desaturation and Its Response to Temperature

“…A single major QTL was detected on chromosome 3 at 4.1 6 0.3 Mb that maps precisely to the location of FAD2. Previous studies using biparental populations also identified a QTL in this region (Hobbs et al, 2004;O'Neill et al, 2012;Sanyal and Linder, 2012). Of the ;3 million sequence variants present in the imputed genomes of the population (Imprialou et al, 2016), the one that is most strongly associated with the trait [-log 10 (P) score of ; 29] is P1 situated in the intron of the FAD2 59 UTR, and six other sequence variants with a -log 10 (P) score greater than 10 also lie either within the 59 UTR intron or in the ;1-kb promoter region of this gene.…”

Multigene Engineering of Triacylglycerol Metabolism Boosts Seed Oil Content in Arabidopsis

“…The glycinin promoter from soybean (Glycine max) was used for DGAT1 overexpression because it drives strong expression throughout embryo maturation (Fatihi et al, 2013), and an SDP1 RNAi construct was placed under the control of the UNKNOWN SEED PROTEIN (USP) promoter from Vicia faba, which is also active throughout embryo maturation (Kelly et al, 2013a). Each construct was transformed into Arabidopsis Columbia-0 (Col-0) plants using Agrobacterium tumefaciens, and approximately 40 transformants were screened for elevated seed percentage oil content in the T2 generation using low-resolution time domain NMR spectroscopy (Hobbs et al, 2004). For each construct, transformants exhibited a range in percentage seed oil content (Supplemental Fig.…”

Arabidopsis Seed Development and Germination Is Associated with Temporally Distinct Metabolic Switches

“…Although some reports on the metabolism of seed development have been published previously they have tended to focus on earlier stages of seed development and on specific biochemical pathways largely concentrating on sugar components Baud and Graham, 2006;Gomez et al, 2006), fatty acids and oil (Cernac and Benning, 2004;Lin et al, 2004;Vigeolas et al, 2004;Gó mez et al, 2005), or specific transcriptional programs (Hobbs et al, 2004;Braybrook et al, 2006). Broader transcriptional studies have also been previously conducted with an emphasis on the stages of development from 5 to 13 DAF (Ruuska et al, 2002).…”