Duplicate polyphenol oxidase genes on barley chromosome 2H and their functional differentiation in the phenol reaction of spikes and grains.
Duplicate polyphenol oxidase genes on barley chromosome 2H and their functional differentiation in the phenol reaction of spikes and grains.
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DOI：
10.1093/jxb/erq211
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发表时间：
2010-09
影响因子：
6.9
通讯作者：
Takeda K
中科院分区：
文献类型：
--
作者：
Taketa S;Matsuki K;Amano S;Saisho D;Himi E;Shitsukawa N;Yuo T;Noda K;Takeda K
多酚氧化酶（Polyphenol oxidases, PPOs）是一种在细胞核中编码并转运到质体中的含铜金属酶。据报道，PPOs导致小麦和大麦最终产品的时间依赖性变色（褐变），这损害了它们的外观质量。在本研究中，用PCR方法扩增了两个大麦PPO同源物，并在小麦PPO基因的铜结合域设计了引物对。利用BAC文库、反相pcr和3′-RACE克隆各PPO基因的全长。连锁分析表明，PPO1和PPO2多态性与山楂酚反应表型共分离。随后的RT-PCR实验表明，PPO1在壳和尾翼中表达，PPO2在颖果中表达。对51份大麦材料中PPO1和PPO2等位基因的变异进行了分析。在PPO1中，51份材料中有40份发现了影响功能重要基序或c端区域的5种氨基酸取代。在PPO2中，在51个被测试的基因中，只有一个突变等位基因在第一个外显子上插入了一个8 bp的终止密码子。这些观察结果表明，PPO1是控制草坪苯酚反应的主要决定因素。PPO1单突变体和PPO1PPO2双突变体的比较表明，PPO2控制颖果腹侧折痕中的苯酚反应。一个hat家族转座子在PPO2启动子区域的插入可能是导致大麦中重复PPO基因不同表达模式的原因。
Polyphenol oxidases (PPOs) are copper-containing metalloenzymes encoded in the nucleus and transported into the plastids. Reportedly, PPOs cause time-dependent discoloration (browning) of end-products of wheat and barley, which impairs their appearance quality. For this study, two barley PPO homologues were amplified using PCR with a primer pair designed in the copper binding domains of the wheat PPO genes. The full-lengths of the respective PPO genes were cloned using a BAC library, inverse-PCR, and 3′-RACE. Linkage analysis showed that the polymorphisms in PPO1 and PPO2 co-segregated with the phenol reaction phenotype of awns. Subsequent RT-PCR experiments showed that PPO1 was expressed in hulls and awns, and that PPO2 was expressed in the caryopses. Allelic variation of PPO1 and PPO2 was analysed in 51 barley accessions with the negative phenol reaction of awns. In PPO1, amino acid substitutions of five types affecting functionally important motif(s) or C-terminal region(s) were identified in 40 of the 51 accessions tested. In PPO2, only one mutant allele with a precocious stop codon resulting from an 8 bp insertion in the first exon was found in three of the 51 accessions tested. These observations demonstrate that PPO1 is the major determinant controlling the phenol reaction of awns. Comparisons of PPO1 single mutants and the PPO1PPO2 double mutant indicate that PPO2 controls the phenol reaction in the crease on the ventral side of caryopses. An insertion of a hAT-family transposon in the promoter region of PPO2 may be responsible for different expression patterns of the duplicate PPO genes in barley.
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影响因子：
3.3
作者：
Lee, Seonghee;Costanzo, Stefano;Caicedo, Ana L.
通讯作者：
Caicedo, Ana L.
影响因子：
2.3
作者：
Demeke, T;Morris, CF;Chang, HG
通讯作者：
Chang, HG
影响因子：
5.1
作者：
HUNT, MD;EANNETTA, NT;STEFFENS, JC
通讯作者：
STEFFENS, JC
DOI：
10.1073/pnas.0611377104
发表时间：
2007-02-27
影响因子：
11.1
作者：
Morrell, Peter L.;Clegg, Michael T.
通讯作者：
Clegg, Michael T.
影响因子：
5.4
作者：
Massa, Alicia N.;Beecher, Brian;Morris, Craig F.
通讯作者：
Morris, Craig F.