Viana V E, Marini N, Finatto T, Ezquer I, Busanello C, Dos Santos R S, Pegoraro C, Colombo L, Costa de Oliveira A
Centro de Genômica e Fitomelhoramento, Departamento de Fitotecnia, Faculdade de Agronomia Eliseu Maciel, , , Brasil.
Centro de Desenvolvimento Tecnológico, , , Brasil.
Genet Mol Res. 2017 Sep 27;16(3):gmr-16-03-gmr.16039694. doi: 10.4238/gmr16039694.
Iron (Fe) is an essential microelement for all living organisms playing important roles in several metabolic reactions. Rice (Oryza sativa L.) is commonly cultivated in paddy fields, where Fe goes through a reduction reaction from Fe to Fe. Since Fe is more soluble, it can reach toxic levels inside plant cells, constituting an important target for studies. Here we aimed to verify morphological changes of different rice genotypes focusing on deciphering the underlying molecular network induced upon Fe excess treatments with special emphasis on the role of four WRKY transcription factors. The transcriptional response peak of these WRKY transcription factors in rice seedlings occurs at 4 days of exposition to iron excess. OsWRKY55-like, OsWRKY46, OsWRKY64, and OsWRKY113 are up-regulated in BR IRGA 409, an iron-sensitive genotype, while in cultivars Nipponbare (moderately resistant) and EPAGRI 108 (resistant) the expression profiles of these transcription factors show similar behaviors. Here is also shown that some cis-regulatory elements known to be involved in other different stress responses can be linked to conditions of iron excess. Overall, here we support the role of WRKY transcription factors in iron stress tolerance with other important steps toward finding why some rice genotypes are more tolerant than others.
铁（Fe）是所有生物必需的微量元素，在多种代谢反应中发挥重要作用。水稻（Oryza sativa L.）通常种植在稻田中，在那里铁会经历从Fe到Fe的还原反应。由于Fe的溶解度更高，它可能在植物细胞内达到有毒水平，这构成了研究的重要目标。在这里，我们旨在验证不同水稻基因型的形态变化，重点是破译铁过量处理后诱导的潜在分子网络，特别强调四个WRKY转录因子的作用。这些WRKY转录因子在水稻幼苗中的转录反应峰值出现在暴露于铁过量的第4天。在铁敏感基因型BR IRGA 409中，类OsWRKY55、OsWRKY46、OsWRKY64和OsWRKY113上调，而在品种日本晴（中度抗性）和EPAGRI 108（抗性）中，这些转录因子的表达谱表现出相似的行为。这里还表明，一些已知参与其他不同应激反应的顺式调控元件可能与铁过量条件有关。总体而言，我们在此支持WRKY转录因子在铁胁迫耐受性中的作用，并朝着找出为何某些水稻基因型比其他基因型更耐受的方向迈出了其他重要步骤。
