Sánchez-Elordi Elena, de Los Ríos Laura Morales, Vicente Carlos, Legaz María-Estrella
Team of Cell Interactions in Plant Symbioses, Faculty of Biology, Complutense University, 12, José Antonio Novais Av., 28040, Madrid, Spain.
J Plant Res. 2019 May;132(3):405-417. doi: 10.1007/s10265-019-01098-7. Epub 2019 Mar 12.
Previous studies have already highlighted the correlation between Sporisorium scitamineum pathogenicity and sugarcane polyamine accumulation. It was shown that high infectivity correlates with an increase in the amount of spermidine, spermine and cadaverine conjugated to phenols in the sensitive cultivars whereas resistant plants mainly produce free putrescine. However, these previous studies did not clarify the role of these polyamides in the disorders caused to the plant. Therefore, the purpose of this research is to clarify the effect of polyamines on the development of smut disease. In this paper, commercial polyamines were firstly assayed on smut teliospores germination. Secondly, effects were correlated to changes in endogenous polyamines after contact with defense sugarcane glycoproteins. Low concentrations of spermidine significantly activated teliospore germination, while putrescine had no activating effect on germination. Interestingly, it was observed that the diamine caused nuclear decondensation and breakage of the teliospore cell wall whereas the treatment of teliospores with spermidine did not induce nuclear decondensation or cell wall breakdown. Moreover, the number of polymerized microtubules increased in the presence of 7.5 mM spermidine but it decreased with putrescine which indicates that polyamines effects on Sporisorium scitamineum teliospore germination could be mediated through microtubules interaction. An increased production of polyamines in smut teliospores has been related to sugarcane resistance to the disease. Teliospores incubation with high molecular mass glycoproteins (HMMG) from the uninoculated resistant variety of sugarcane, Mayari 55-14, caused an increase of the insoluble fraction of putrescine, spermidine and spermine inside the teliospore cells. Moreover, the level of the soluble fraction of spermidine (S fraction) increased inside teliospores and the excess was released to the medium. The HMMG glycoproteins purified from Mayarí 55-14 plants previously inoculated with the pathogen significantly increased the levels of both retained and secreted soluble putrescine and spermidine. Polyamines levels did not increase in teliospores after incubation with HMMG produced by non resistant variety Barbados 42231 which could be related to the incapacity of these plants to defend themselves against smut disease. Thus, a hypothesis about the role of polyamines in sugarcane-smut interaction is explained.
先前的研究已经强调了甘蔗黑粉菌致病性与甘蔗多胺积累之间的相关性。研究表明，在敏感品种中，高侵染性与结合到酚类物质上的亚精胺、精胺和尸胺含量增加相关，而抗性植株主要产生游离的腐胺。然而，这些先前的研究并未阐明这些多胺在对植物造成的病症中的作用。因此，本研究的目的是阐明多胺对黑粉病发展的影响。在本文中，首先对市售多胺进行了黑粉菌冬孢子萌发试验。其次，将这些影响与接触防御性甘蔗糖蛋白后内源性多胺的变化相关联。低浓度的亚精胺显著激活冬孢子萌发，而腐胺对萌发没有激活作用。有趣的是，观察到二胺导致冬孢子细胞核解聚和细胞壁破裂，而用亚精胺处理冬孢子不会诱导细胞核解聚或细胞壁破裂。此外，在7.5 mM亚精胺存在下，聚合微管的数量增加，但在腐胺存在下减少，这表明多胺对甘蔗黑粉菌冬孢子萌发的影响可能是通过微管相互作用介导的。黑粉菌冬孢子中多胺产量的增加与甘蔗对该病的抗性有关。用未接种病原菌的抗性甘蔗品种Mayari 55 - 14的高分子量糖蛋白（HMMG）培养冬孢子，导致冬孢子细胞内腐胺、亚精胺和精胺的不溶性部分增加。此外，冬孢子内亚精胺的可溶性部分（S部分）水平增加，多余部分释放到培养基中。从先前接种病原菌的Mayarí 55 - 14植株中纯化的HMMG糖蛋白显著增加了保留和分泌的可溶性腐胺和亚精胺的水平。用非抗性品种Barbados 42231产生的HMMG培养后，冬孢子中的多胺水平没有增加，这可能与这些植株无法抵御黑粉病有关。因此，解释了一个关于多胺在甘蔗 - 黑粉菌相互作用中作用的假说。
