植物MLO蛋白研究进展
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摘要
Mildew resistance locus O(MLO)蛋白是植物特有的一类蛋白家族,其中的部分成员是白粉病菌成功侵染寄主植物的必要因子。一个或多个MLO基因的功能缺失突变可赋予植物对白粉病菌广谱且持久的抗性,mlo介导的白粉病抗性在抗病育种中发挥了重要作用。植物中的MLO蛋白可以分为7个亚家族,除了参与植物与白粉病菌的互作外,不同亚家族的MLO蛋白还有很多其他功能。本文对MLO蛋白的特征、分类、功能进行了归纳,介绍了植物与白粉病抗性相关的mlo突变体特征及抗病机制,并对MLO基因的功能、作用机理研究及其在植物抗病育种中利用应注意的问题进行了讨论。
Mildew resistance locus O(MLO) is a plant-specific protein family, some of which are essential factors for the powdery mildew successfully infection. Loss-of-function mutation of one or more MLO genes can confer the host plants durable broad-spectrum resistance to powdery mildew. mlo-based resistance has been successfully employed in plant resistance breeding. Plant MLO proteins can be divided into 7 subfamilies. In addition to the plant-powdery mildew interaction, MLOs from different subfamilies may have different functions. This review introduces the characteristic, categorization and function of MLO proteins, as well as the features and possible resistance mechanisms of mlo mutant. At last, we discuss the function mechanism of MLO proteins, the utilization of MLO genes in the plant disease resistance breeding and the problems we should pay attention to.
Mildew resistance locus O(MLO) is a plant-specific protein family, some of which are essential factors for the powdery mildew successfully infection. Loss-of-function mutation of one or more MLO genes can confer the host plants durable broad-spectrum resistance to powdery mildew. mlo-based resistance has been successfully employed in plant resistance breeding. Plant MLO proteins can be divided into 7 subfamilies. In addition to the plant-powdery mildew interaction, MLOs from different subfamilies may have different functions. This review introduces the characteristic, categorization and function of MLO proteins, as well as the features and possible resistance mechanisms of mlo mutant. At last, we discuss the function mechanism of MLO proteins, the utilization of MLO genes in the plant disease resistance breeding and the problems we should pay attention to.
引文
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Berg JA,Appiano M,Bijsterbosch G(2017).Functional characterization of cucumber(Cucumis sativus L.)Clade VMLO genes.BMC Plant Biol,17:80
Berg JA,Appiano M,Martínez MS,et al(2015).A transposable element insertion in the susceptibility gene Csa M-LO8 results in hypocotyl resistance to powdery mildew in cucumber.BMC Plant Biol,15:243
Bhat RA,Miklis M,Schmelzer E,et al(2005).Recruitment and interaction dynamics of plant penetration resistance components in a plasma membrane microdomain.Proc Natl Acad Sci USA,102(8):3135-3140
Bidzinski P,Noir S,Shahi S,et al(2014).Physiological characterization and genetic modifiers of aberrant root thigmomorphogenesis in mutants of Arabidopsis thaliana MILDEW LOCUS O genes.Plant Cell Environ,37:2738-2753
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Bombarely A,Rosli HG,Vrebalov J,et al(2012).A draft genome sequence of Nicotiana benthamiana to enhance molecular plant-microbe biology research.Mol Plant Microbe Interact,25:1523-1530
Bracuto V,Appiano M,Ricciardi L,et al(2017).Functional characterization of the powdery mildew susceptibility gene Sm MLO1 in eggplant(Solanum melongena L.).Transgenic Res,26(3):323-330
Brzostowski JA,Kimmel AR(2001).Signaling at zero G:G-protein-independent functions for 7-TM receptors.Trends Biochem Sci,26(5):291-297
Büschges R,Hollricher K,Panstruga R,et al(1997).The barley Mlo gene:a novel control element of plant pathogen resistance.Cell,88:695-705
Chandran D,Inada N,Hather G,et al(2010).Laser microdissection of Arabidopsis cells at the powdery mildew infection site reveals site-specific processes and regulators.Proc Natl Acad Sci USA,107:460-465
Chen Y,Wang Y,Zhang H(2014).Genome-wide analysis of the mildew resistance locus(MLO)gene family in tomato(Solanum lycopersicum L.).Plant Omics J,7:87-93
Chen Z,Hartmann HA,Wu MJ,et al(2006).Expression analysis of the At MLO gene family encoding plant-specific seven-transmembrane domain proteins.Plant Mol Biol,60:583-597
Chen Z,Noir S,Kwaaitaal M,et al(2009).Two seven-transmembrane domain MILDEW RESISTANCE LOCUS Oproteins cofunction in Arabidopsis root thigmomorphogenesis.Plant Cell,21:1972-1991
Collins NC,Thordal-Christensen H,Lipka V,et al(2003).SNARE-protein-mediated disease resistance at the plant cell wall.Nature,425(6961):973-977
Consonni C,Bednarek P,Humphry M,et al(2010).Tryptophan-derived metabolites are required for antifungal defense in the Arabidopsis mlo2 mutant.Plant Physiol,152:1544-1561
Consonni C,Humphry ME,Hartmann HA,et al(2006).Conserved requirement for a plant host cell protein in powdery mildew pathogenesis.Nat Genet,38:716-720
Davis TC,Jones DS,Dino AJ,et al(2017).Arabidopsis thaliana MLO genes are expressed in discrete domains during reproductive development.Plant Reprod,30(4):185-195
Deshmukh R,Singh VK,Singh BD(2014).Comparative phylogenetic analysis of genome-wide Mlo gene family members from Glycine max and Arabidopsis thaliana.Mol Genet Genomics,289:345-359
Deshmukh R,Singh VK,Singh BD(2016).Comparative analysis of genome-wide Mlo gene family in Cajanus cajan and Phaseolus vulgaris.Genetica,144(2):229-241
Deshmukh R,Singh VK,Singh BD(2017).Mining the Cicer arietinum genome for the mildew locus O(Mlo)gene family and comparative evolutionary analysis of the Mlo genes from Medicago truncatula and some other plant species.J Plant Res,130(2):239-253
Devoto A,Hartmann HA,Piffanelli P,et al(2003).Molecular phylogeny and evolution of the plant-specific seven-transmembrane MLO family.J Mol Evol,56:77-88
Devoto A,Piffanelli P,Nilsson IM,et al(1999).Topology,subcellular localization,and sequence diversity of the Mlo family in plants.J Biol Chem,274:34993-35004
Dong X,Zhao Y,Ran X,et al(2017).Overexpression of a new chitinase gene Eu CHIT2 enhances resistance to Erysiphe cichoracearum DC.in tobacco plants.Int J Mol Sci,18(11):2361-2366
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