Loss of TaIRX9b gene function in wheat decreases chain length and amount of arabinoxylan in grain but increases cross-linking.
Loss of TaIRX9b gene function in wheat decreases chain length and amount of arabinoxylan in grain but increases cross-linking.
复制标题
小麦中TAIRX9B基因功能的丧失会降低晶粒中的链长和阿拉伯素的量，但会增加交联。
DOI：
10.1111/pbi.13393
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发表时间：
2020-11
影响因子：
13.8
通讯作者：
Mitchell RAC
中科院分区：
文献类型：
--
作者：
Pellny TK;Patil A;Wood AJ;Freeman J;Halsey K;Plummer A;Kosik O;Temple H;Collins JD;Dupree P;Berry S;Shewry PR;Lovegrove A;Phillips AL;Mitchell RAC
小麦在所有组织的细胞壁中含有丰富的木聚糖，但在胚乳中，存在一种仅被阿拉伯糖取代的不寻常形式的木聚糖（阿拉伯木聚糖; AX），其具有长链和低水平的阿魏酸化，其中一部分可在水中提取（WE-AX）。WE-AX作为可溶性膳食纤维，但也会从谷物中产生粘性提取物，这对小麦的某些非食品用途是有害的。在这里，我们表明，糖基转移酶家族43小麦基因丰富的胚乳中表达的补充拟南芥irx 9突变体，因此命名的三个同源基因TaIRX 9 b。我们通过从诱变的六倍体小麦群体中堆叠这些同源物的功能丧失等位基因来产生TaIRX 9 b组成型敲除的小麦品系，导致谷物提取物粘度降低50%-80%。由于提取物粘度的变化，来自这些三重堆叠线的谷物的WE-AX分子的量和链长降低。三重堆叠的未成熟小麦谷粒切片的成像显示，用识别AX中的表位的LM 11抗体消除胚乳中的免疫标记，但也显示所有细胞类型（包括胚乳）中明显正常的细胞大小和形状。我们鉴定了三叠胚乳的差异表达基因，表明发生了补偿性变化以维持胚乳细胞壁的完整性。与此一致，我们观察到阿魏酸二聚化增加和三重堆叠中WE-AX分子的交联增加。因此，这些缺乏功能性TaIRX 9 b的新型小麦品系提供了对小麦胚乳细胞壁控制的深入了解。
Wheat contains abundant xylan in cell walls of all tissues, but in endosperm, there is an unusual form of xylan substituted only by arabinose (arabinoxylan; AX) that has long chains and low levels of feruloylation, a fraction of which is extractable in water (WE‐AX). WE‐AX acts as soluble dietary fibre but also gives rise to viscous extracts from grain, a detrimental trait for some non‐food uses of wheat. Here, we show that a glycosyl transferase family 43 wheat gene abundantly expressed in endosperm complements the Arabidopsis irx9 mutant and so name the three homoeologous genes TaIRX9b. We generated wheat lines with a constitutive knockout of TaIRX9b by stacking loss‐of‐function alleles for these homeologues from a mutagenized hexaploid wheat population resulting in decreases in grain extract viscosity of 50%–80%. The amount and chain length of WE‐AX molecules from grain of these triple‐stack lines was decreased accounting for the changes in extract viscosity. Imaging of immature wheat grain sections of triple‐stacks showed abolition of immunolabelling in endosperm with LM11 antibody that recognizes epitopes in AX, but also showed apparently normal cell size and shape in all cell types, including endosperm. We identified differentially expressed genes from endosperm of triple‐stacks suggesting that compensatory changes occur to maintain this endosperm cell wall integrity. Consistent with this, we observed increased ferulate dimerization and increased cross‐linking of WE‐AX molecules in triple‐stacks. These novel wheat lines lacking functional TaIRX9b therefore provide insight into control of wheat endosperm cell walls.
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DOI：
10.1111/nph.14970
发表时间：
2018-04
期刊：
The New phytologist
影响因子：
--
作者：
de Souza WR;Martins PK;Freeman J;Pellny TK;Michaelson LV;Sampaio BL;Vinecky F;Ribeiro AP;da Cunha BADB;Kobayashi AK;de Oliveira PA;Campanha RB;Pacheco TF;Martarello DCI;Marchiosi R;Ferrarese-Filho O;Dos Santos WD;Tramontina R;Squina FM;Centeno DC;Gaspar M;Braga MR;Tiné MAS;Ralph J;Mitchell RAC;Molinari HBC
通讯作者：
Molinari HBC
在编码与淀粉合成的关键酶的基因上合并突变会影响小麦颗粒中的双链糖含量，碳水化合物分配和硬度。
影响因子：
13.8
作者：
Botticella E;Sestili F;Sparla F;Moscatello S;Marri L;Cuesta-Seijo JA;Falini G;Battistelli A;Trost P;Lafiandra D
通讯作者：
Lafiandra D
影响因子：
4.3
作者：
Hyde LS;Pellny TK;Freeman J;Michaelson LV;Simister R;McQueen-Mason SJ;Mitchell RAC
通讯作者：
Mitchell RAC
影响因子：
7.2
作者：
Bromley, Jennifer R.;Busse-Wicher, Marta;Dupree, Paul
通讯作者：
Dupree, Paul
影响因子：
2.4
作者：
Finnie, S. M.;Bettge, A. D.;Morris, C. F.
通讯作者：
Morris, C. F.