Down-regulation of acetolactate synthase compromises Ol-1- mediated resistance to powdery mildew in tomato.
Down-regulation of acetolactate synthase compromises Ol-1- mediated resistance to powdery mildew in tomato.
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DOI：
10.1186/1471-2229-14-32
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发表时间：
2014-01-17
影响因子：
5.3
通讯作者：
Bai Y
中科院分区：
文献类型：
--
作者：
Gao D;Huibers RP;Loonen AE;Visser RG;Wolters AM;Bai Y
在比较白粉病（Oidium neolycopersici）敏感的番茄栽培品种Moneymaker（MM）和携带抗性基因Ol-1或Ol-4的近等基因系（NIL）之间的转录水平的cDNA-AFLP分析中，发现转录衍生片段（TDF）M11 E69 -195存在于NIL-01 -1中，但在MM和NIL-01 -4中不存在。该TDF显示与乙酰乳酸合酶（ALS）的同源性。ALS是支链氨基酸缬氨酸、亮氨酸和异亮氨酸生物合成的关键酶，也是商业除草剂的靶标。在番茄基因组序列中鉴定出ALS的3个同源基因ALS 1、ALS 2、ALS 3。ALS 1和ALS 2表现出高度的相似性，而ALS 3则更加发散。通过病毒诱导的基因沉默（VIGS）使NIL-01 -1中的ALS 1和ALS 2瞬时沉默，导致对O. neolycopersici（On）. VIGS结果通过使用靶向ALS 1和ALS 2的RNAi构建体稳定转化NIL-01 -1来证实。相反，通过RNAi构建体单独沉默三种ALS基因不损害NIL-01 -1的抗性。应用除草剂氯磺隆对NIL-01 -1模拟VIGS表型，并导致其对On. Mm的抗性丧失。还用氯磺隆处理了携带核苷酸结合位点和富含亮氨酸重复序列（NB-LRR）抗性基因的敏感MM和On-R抗性系NIL-01 -4。MM的敏感性和NIL-01 -4的耐药性均未受到影响。ALS既不参与基础防御，也不参与NB-LRR型抗性基因赋予的抗性。相反，它专门参与Ol-1介导的番茄白粉病抗性，这表明ALS诱导的氨基酸稳态变化对于Ol-1赋予的抗性很重要。
In a cDNA-AFLP analysis comparing transcript levels between powdery mildew (Oidium neolycopersici)-susceptible tomato cultivar Moneymaker (MM) and near isogenic lines (NILs) carrying resistance gene Ol-1 or Ol-4, a transcript-derived fragment (TDF) M11E69-195 was found to be present in NIL-Ol-1 but absent in MM and NIL-Ol-4. This TDF shows homology to acetolactate synthase (ALS). ALS is a key enzyme in the biosynthesis of branched-chain amino acids valine, leucine and isoleucine, and it is also a target of commercial herbicides. Three ALS homologs ALS1, ALS2, ALS3 were identified in the tomato genome sequence. ALS1 and ALS2 show high similarity, whereas ALS3 is more divergent. Transient silencing of both ALS1 and ALS2 in NIL-Ol-1 by virus-induced gene silencing (VIGS) resulted in chlorotic leaf areas that showed increased susceptibility to O. neolycopersici (On). VIGS results were confirmed by stable transformation of NIL-Ol-1 using an RNAi construct targeting both ALS1 and ALS2. In contrast, silencing of the three ALS genes individually by RNAi constructs did not compromise the resistance of NIL-Ol-1. Application of the herbicide chlorsulfuron to NIL-Ol-1 mimicked the VIGS phenotype and caused loss of its resistance to On. Susceptible MM and On-resistant line NIL-Ol-4 carrying a nucleotide binding site and leucine rich repeat (NB-LRR) resistance gene were also treated with chlorsulfuron. Neither the susceptibility of MM nor the resistance of NIL-Ol-4 was affected. ALS is neither involved in basal defense, nor in resistance conferred by NB-LRR type resistance genes. Instead, it is specifically involved in Ol-1-mediated resistance to tomato powdery mildew, suggesting that ALS-induced change in amino acid homeostasis is important for resistance conferred by Ol-1.
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影响因子：
64.8
作者：
Liu, Shiming;Kandoth, Pramod K.;Meksem, Khalid
通讯作者：
Meksem, Khalid
影响因子：
2.9
作者：
Lovdal, Trond;Lillo, Cathrine
通讯作者：
Lillo, Cathrine
影响因子：
1.7
作者：
Nolte, SA;Young, BG;Lightfoot, DA
通讯作者：
Lightfoot, DA
DOI：
10.1199/tab.0137
发表时间：
2010-01-01
期刊：
The arabidopsis book
影响因子：
--
作者：
Binder, Stefan
通讯作者：
Binder, Stefan
影响因子：
3.7
作者：
Huibers RP;Loonen AE;Gao D;Van den Ackerveken G;Visser RG;Bai Y
通讯作者：
Bai Y