Heterologous expression and transcript analysis of gibberellin biosynthetic genes of grasses reveals novel functionality in the GA3ox family.
Heterologous expression and transcript analysis of gibberellin biosynthetic genes of grasses reveals novel functionality in the GA3ox family.
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DOI：
10.1186/s12870-015-0520-7
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发表时间：
2015-06-05
影响因子：
5.3
通讯作者：
Phillips AL
中科院分区：
文献类型：
--
作者：
Pearce S;Huttly AK;Prosser IM;Li YD;Vaughan SP;Gallova B;Patil A;Coghill JA;Dubcovsky J;Hedden P;Phillips AL
赤霉素 (GA) 途径在植物发育的调节中发挥着核心作用，2-氧化戊二酸依赖性双加氧酶（2-ODD：GA20ox、GA3ox、GA2ox）催化生物合成途径中的后续步骤，对于调节生物活性 GA 水平特别重要。尽管赤霉素对作物产量和品质具有重要影响，但我们对小麦和大麦发育过程中赤霉素生物合成调控的了解仍然有限。在本研究中，我们鉴定或组装了编码小麦、大麦和二穗短柄草的 GA 2-ODD 的基因，并通过异源表达和转录本分析来表征小麦基因。小麦、大麦和短柄草基因组均含有在水稻中发现的 GA20ox、GA3ox 和 GA2ox 基因的直系同源拷贝，但 OsGA3ox1 和 OsGA2ox5 除外，这些基因在这些物种中不存在。还鉴定了 2-ODD 基因的一些其他旁系同源物：值得注意的是，小麦 B 基因组中与 GA3ox2 相关的新基因被证明可编码 GA 1-氧化酶，命名为 TaGA1ox-B1。这种酶可能是发育中的小麦籽粒中存在大量 1β-羟基化 GA 的原因。我们还在大麦中鉴定了一个相关基因，位于 TaGA1ox-B1 的同线位置，编码 GA 3,18-二羟化酶，这同样解释了大麦籽粒中异常 GA 的积累。转录本分析表明，不同类别 2-ODD 的一些旁系同源物主要在单一组织或特定发育阶段表达。特别是，TaGA20ox3、TaGA1ox1、TaGA3ox3 和 TaGA2ox7 主要在发育中的谷物中表达。对谷物特异性基因表达的更详细分析表明，虽然生物合成基因的转录本在胚乳中最丰富，但编码失活和信号成分的基因在种皮和果皮中表达更高。小麦和大麦中编码 GA 途径 2-ODD 酶的多基因家族的全面表达和功能特征将为更好地了解这些物种中 GA 调节的发育提供基础。该分析揭示了小麦中存在一种新型的胚乳特异性 GA 1-氧化酶，而大麦中存在一种相关的 GA 3,18-二羟化酶，它们可能在籽粒膨大和发育过程中发挥重要作用。本文的在线版本 (doi:10.1186/s12870-015-0520-7) 包含补充材料，可供授权用户使用。
The gibberellin (GA) pathway plays a central role in the regulation of plant development, with the 2-oxoglutarate-dependent dioxygenases (2-ODDs: GA20ox, GA3ox, GA2ox) that catalyse the later steps in the biosynthetic pathway of particularly importance in regulating bioactive GA levels. Although GA has important impacts on crop yield and quality, our understanding of the regulation of GA biosynthesis during wheat and barley development remains limited. In this study we identified or assembled genes encoding the GA 2-ODDs of wheat, barley and Brachypodium distachyon and characterised the wheat genes by heterologous expression and transcript analysis. The wheat, barley and Brachypodium genomes each contain orthologous copies of the GA20ox, GA3ox and GA2ox genes identified in rice, with the exception of OsGA3ox1 and OsGA2ox5 which are absent in these species. Some additional paralogs of 2-ODD genes were identified: notably, a novel gene in the wheat B genome related to GA3ox2 was shown to encode a GA 1-oxidase, named as TaGA1ox-B1. This enzyme is likely to be responsible for the abundant 1β-hydroxylated GAs present in developing wheat grains. We also identified a related gene in barley, located in a syntenic position to TaGA1ox-B1, that encodes a GA 3,18-dihydroxylase which similarly accounts for the accumulation of unusual GAs in barley grains. Transcript analysis showed that some paralogs of the different classes of 2-ODD were expressed mainly in a single tissue or at specific developmental stages. In particular, TaGA20ox3, TaGA1ox1, TaGA3ox3 and TaGA2ox7 were predominantly expressed in developing grain. More detailed analysis of grain-specific gene expression showed that while the transcripts of biosynthetic genes were most abundant in the endosperm, genes encoding inactivation and signalling components were more highly expressed in the seed coat and pericarp. The comprehensive expression and functional characterisation of the multigene families encoding the 2-ODD enzymes of the GA pathway in wheat and barley will provide the basis for a better understanding of GA-regulated development in these species. This analysis revealed the existence of a novel, endosperm-specific GA 1-oxidase in wheat and a related GA 3,18-dihydroxylase enzyme in barley that may play important roles during grain expansion and development. The online version of this article (doi:10.1186/s12870-015-0520-7) contains supplementary material, which is available to authorized users.
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DOI：
10.1039/p19820000689
发表时间：
1982-01-01
期刊：
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1
影响因子：
--
作者：
KIRKWOOD, PS;MACMILLAN, J
通讯作者：
MACMILLAN, J
影响因子：
4.3
作者：
Appleford, NEJ;Evans, DJ;Hedden, P
通讯作者：
Hedden, P
影响因子：
4.9
作者：
Hirano K;Aya K;Hobo T;Sakakibara H;Kojima M;Shim RA;Hasegawa Y;Ueguchi-Tanaka M;Matsuoka M
通讯作者：
Matsuoka M
影响因子：
56.9
作者：
Choulet, Frederic;Alberti, Adriana;Feuillet, Catherine
通讯作者：
Feuillet, Catherine
影响因子：
11.4
作者：
Hedden, P
通讯作者：
Hedden, P