The isolation of high-quality RNA from strawberry leaves and fruits is notoriously cumbersome. Both tissues are extremely rich in active secondary metabolites, as phenolics and pigments that inevitably perturb the isolation of RNA. Many protocols have been developed to address this problem. However, they are either costly, or time-consuming, in particular for high number of many plant samples. We describe here a new method with an easy-to-handle approach to obtain high-quality RNA from strawberry leaves and fruits. The method, referred to as double lysis, uses a novel combination of CTAB and Trizol protocols. Compared to conventional Trizol-dependent protocols, either used individually, or in a commercial spin-column kit, the new method yields RNA at lower costs, but of significantly improved quality. The RNA obtained by double lysis was very pure as indicated by 260/280 ratios of 2.06 (leaves) and 2.07 (fruits), while 260/230 ratio was 2.07 and 1.75, respectively. Also visually, RNA sediments from double lysis showed a white color, indicative of efficient elimination of polyphenolics and pigments. In contrast, traditional Trizol method produced reddish precipitates. The purity of RNA isolated by double lysis enabled successful removal of genomic DNA and, thus, allowed for more efficient cDNA synthesis and RT-PCR. In addition, the suggested method is able to yield RNA with fully preserved integrity from strawberry leaves, fruits in addition to petals and roots. Double lysis is a new RNA isolation protocol developed through the integrative coupling of CTAB and Trizol reagents. The method is cost-effective, robust, time-saving, and can cope even with recalcitrant plant tissues with high contents of phenolics and pigments, such as strawberry leaves and fruits.

中文翻译：

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双重裂解：一种节省时间的综合方法，可从草莓中提取高质量的RNA。

从草莓叶片和果实中分离出高质量的RNA非常麻烦。两种组织都富含活性次生代谢产物，因为酚类和色素不可避免地干扰了RNA的分离。已经开发出许多协议来解决这个问题。然而，它们要么昂贵要么耗时，尤其对于大量的许多植物样品而言。我们在这里描述了一种易于处理的新方法，可以从草莓叶片和果实中获得高质量的RNA。该方法称为双重裂解，它使用CTAB和Trizol方案的新颖组合。与传统的依赖Trizol的方案（单独使用或在商业旋转柱试剂盒中使用）相比，该新方法以较低的成本生产RNA，但质量显着提高。通过两次裂解获得的RNA非常纯净，如260/280的比例为2.06（叶）和2.07（水果）所示，而260/230的比例分别为2.07和1.75。同样在视觉上，双重裂解产生的RNA沉淀物显示为白色，表明有效消除了多酚和色素。相比之下，传统的Trizol方法产生红色沉淀。通过双重裂解分离的RNA纯度能够成功去除基因组DNA，因此可以实现更有效的cDNA合成和RT-PCR。另外，所建议的方法能够从草莓叶，果实以及花瓣和根部中获得具有完全保留的完整性的RNA。双重裂解是通过CTAB和Trizol试剂的整合偶联开发的一种新的RNA分离方案。该方法具有成本效益，功能强大，节省时间，