The barley MLO modulator of defense and cell death is responsive to biotic and abiotic stress stimuli
The barley MLO modulator of defense and cell death is responsive to biotic and abiotic stress stimuli
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DOI：
10.1104/pp.010954
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发表时间：
2002-07-01
期刊：
影响因子：
7.4
通讯作者：
Schulze-Lefert, P
中科院分区：
文献类型：
--
作者：
Piffanelli, P;Zhou, FS;Schulze-Lefert, P
大麦缺乏七跨膜结构域的MLO蛋白使其对小麦白粉菌产生抗性。霍尔迪(BGH)。为了拓宽MLO结构/功能研究的基础，我们对额外的MLO抗性等位基因进行了测序，其中两个等位基因只赋予部分抗性。野生型MLO在真菌试图穿透表皮细胞壁的时候抑制了细胞壁受限的过氧化氢爆发，在叶肉细胞中，它抑制了第二次氧化爆发和细胞死亡。虽然BGH诱导的MLO植物细胞死亡在空间和时间上与抗性是分离的，但我们证明了这两个过程是联系在一起的。未接种突变体MLO植株表现出自发的叶肉细胞死亡，这似乎是加速叶片衰老的一部分。在BGH、水稻稻瘟病、伤害、百草枯处理、小麦白粉病衍生碳水化合物激发子和叶片衰老期间，MLO转录丰度增加。这表明MLO广泛参与细胞死亡保护以及对生物和非生物胁迫的反应。
Lack of the barley (Hordeum vulgare) seven-transmembrane domain MLO protein confers resistance against the fungal pathogen Blumeria graminis f. sp. hordei (Bgh). To broaden the basis for MLO structure/function studies, we sequenced additional mlo resistance alleles, two of which confer only partial resistance. Wild-type MLO dampens the cell wall-restricted hydrogen peroxide burst at points of attempted fungal penetration of the epidermal cell wall, and in subtending mesophyll cells, it suppresses a second oxidative burst and cell death. Although the Bgh-induced cell death in mlo plants is spatially and temporally separated from resistance, we show that the two processes are linked. Uninoculated mutant mlo plants exhibit spontaneous mesophyll cell death that appears to be part of accelerated leaf senescence. Mlo transcript abundance increases in response to Bgh, rice (Oryza sativa) blast, wounding, paraquat treatment, a wheat powdery mildew-derived carbohydrate elicitor, and during leaf senescence. This suggests a broad involvement of Mlo in cell death protection and in responses to biotic and abiotic stresses.