Genome-wide association study reveals the genetic complexity of fructan accumulation patterns in barley grain

TY - JOUR

T1 - Genome-wide association study reveals the genetic complexity of fructan accumulation patterns in barley grain

AU - Matros, Andrea

AU - Houston, Kelly

AU - Tucker, Matthew R.

AU - Schreiber, Miriam

AU - Berger, Bettina

AU - Aubert, Matthew K.

AU - Wilkinson, Laura G.

AU - Witzel, Katja

AU - Waugh, Robbie

AU - Seiffert, Udo

AU - Burton, Rachel A.

N1 - This work was supported by grants from the German Research Foundation (DFG, MA 4814/3-1 & 3-2) to Andrea Matros and the Australian Research Council (ARC) Centre of Excellence in Plant Energy Biology (http://www.plantenergy.uwa.edu.au/) to Rachel Burton. Kelly Houston and Robbie Waugh acknowledge the support of the Rural & Environment Science & Analytical Services Division of the Scottish Government

PY - 2021/3/29

Y1 - 2021/3/29

N2 - We profiled the grain oligosaccharide content of 154 two-row spring barley genotypes and quantified 27 compounds, mainly inulin- and neoseries-type fructans, showing differential abundance. Clustering revealed two profile groups where the 'high' set contained greater amounts of sugar monomers, sucrose, and overall fructans, but lower fructosylraffinose. A genome-wide association study (GWAS) identified a significant association for the variability of two fructan types: neoseries-DP7 and inulin-DP9, which showed increased strength when applying a novel compound ratio-GWAS approach. Gene models within this region included three known fructan biosynthesis genes (fructan:fructan 1-fructosyltransferase, sucrose:sucrose 1-fructosyltransferase, and sucrose:fructan 6-fructosyltransferase). Two other genes in this region, 6(G)-fructosyltransferase and vacuolar invertase1, have not previously been linked to fructan biosynthesis and showed expression patterns distinct from those of the other three genes, including exclusive expression of 6(G)-fructosyltransferase in outer grain tissues at the storage phase. From exome capture data, several single nucleotide polymorphisms related to inulin- and neoseries-type fructan variability were identified in fructan:fructan 1-fructosyltransferase and 6(G)-fructosyltransferase genes. Co-expression analyses uncovered potential regulators of fructan biosynthesis including transcription factors. Our results provide the first scientific evidence for the distinct biosynthesis of neoseries-type fructans during barley grain maturation and reveal novel gene candidates likely to be involved in the differential biosynthesis of various types of fructan in barley.

AB - We profiled the grain oligosaccharide content of 154 two-row spring barley genotypes and quantified 27 compounds, mainly inulin- and neoseries-type fructans, showing differential abundance. Clustering revealed two profile groups where the 'high' set contained greater amounts of sugar monomers, sucrose, and overall fructans, but lower fructosylraffinose. A genome-wide association study (GWAS) identified a significant association for the variability of two fructan types: neoseries-DP7 and inulin-DP9, which showed increased strength when applying a novel compound ratio-GWAS approach. Gene models within this region included three known fructan biosynthesis genes (fructan:fructan 1-fructosyltransferase, sucrose:sucrose 1-fructosyltransferase, and sucrose:fructan 6-fructosyltransferase). Two other genes in this region, 6(G)-fructosyltransferase and vacuolar invertase1, have not previously been linked to fructan biosynthesis and showed expression patterns distinct from those of the other three genes, including exclusive expression of 6(G)-fructosyltransferase in outer grain tissues at the storage phase. From exome capture data, several single nucleotide polymorphisms related to inulin- and neoseries-type fructan variability were identified in fructan:fructan 1-fructosyltransferase and 6(G)-fructosyltransferase genes. Co-expression analyses uncovered potential regulators of fructan biosynthesis including transcription factors. Our results provide the first scientific evidence for the distinct biosynthesis of neoseries-type fructans during barley grain maturation and reveal novel gene candidates likely to be involved in the differential biosynthesis of various types of fructan in barley.

KW - 6G-FFT

KW - Barley

KW - GWAS

KW - expression analysis

KW - fructans

KW - grain

KW - neoseries

KW - oligosaccharides

KW - ratio-GWAS

UR - https://www.scopus.com/pages/publications/85104849083

U2 - 10.1093/jxb/erab002

DO - 10.1093/jxb/erab002

M3 - Article

C2 - 33421064

SN - 0022-0957

VL - 72

SP - 2383

EP - 2402

JO - Journal of Experimental Botany

JF - Journal of Experimental Botany

IS - 7

ER -