Franco Flávia P, Dias Renata O, Toyama Danyelle, Henrique-Silva Flávio, Moura Daniel S, Silva-Filho Marcio C
Departamento de Genética, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, Brazil.
Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, Brazil.
Front Plant Sci. 2019 Jan 7;9:1916. doi: 10.3389/fpls.2018.01916. eCollection 2018.
SUGARWIN1 and 2 are defense proteins from sugarcane. Their gene expression is known to be induced in response to wound and damage. Although the recombinant SUGARWIN protein does not affect insect development, it promotes significant morphological and physiological changes in and , which lead to fungal cell death via apoptosis. In this study, we deepen our understanding of the role of SUGARWINs in plant defense and the molecular mechanisms by which these proteins affect fungi by elucidating their molecular targets. Our results show that SUGARWINs play an important role in plant defense against opportunistic pathogens. We demonstrated that are induced by , and the induction of SUGARWINs can vary among sugarcane varieties. The sugarcane variety exhibiting the highest level of induction exhibited a considerable reduction in infection. Furthermore, SUGARWIN1 exhibited ribonuclease, chitosanase, and chitinase activity, whereas SUGARWIN2 exhibited only chitosanase activity. This variable enzymatic specificity seems to be the result of divergent amino acid composition within the substrate-binding site.
SUGARWIN1和SUGARWIN2是甘蔗中的防御蛋白。已知它们的基因表达会因伤口和损伤而被诱导。尽管重组SUGARWIN蛋白不影响昆虫发育，但它会促使 和 发生显著的形态和生理变化，通过凋亡导致真菌细胞死亡。在本研究中，我们通过阐明其分子靶点，加深了对SUGARWINs在植物防御中的作用以及这些蛋白影响真菌的分子机制的理解。我们的结果表明，SUGARWINs在植物抵御机会性病原体中发挥重要作用。我们证明 会诱导 ，并且SUGARWINs的诱导在不同甘蔗品种间可能存在差异。表现出最高水平 诱导的甘蔗品种在 感染方面有显著降低。此外，SUGARWIN1表现出核糖核酸酶、壳聚糖酶和几丁质酶活性，而SUGARWIN2仅表现出壳聚糖酶活性。这种可变的酶特异性似乎是底物结合位点内氨基酸组成不同的结果。
