Efficient RNA extraction method for acquiring high-quality RNA from various tissues of the fiber crop abaca, Née.

Isolation of high-quality RNA from abaca is very challenging due to the presence of polyphenols, polysaccharides, and its high fiber content. In this study, we compared six extraction methods across three tissue types and different developmental stages (-grown young versus field-grown mature tissue). The Invitrogen PureLink RNA kit proved to be the most efficient in extracting RNA from young abaca tissues (leaves, pseudostem, and corm). The quality of RNA extracted from young tissues was further assessed by RNA-seq applications, with raw sequencing reads mapping back to the reference genome at rates of 86.0%-90.4%. The SDS-TRIzol-method modified with an added on-column DNAse I treatment was used to extract RNA from mature tissues (leaves, midrib, and pseudostem). RNA isolated from five cultivars and across three mature tissue types showed RNA yield per 100 mg of fresh weight ranges from 0.57 to 10.94 µg and RNA integrity number (RIN) scores of more than 7.0 for all tissue types. Our improved SDS-Trizol method for RNA extraction described here is simple and yields good quality RNAs from mature abaca tissues while the PureLink RNA kit is suitable for extracting RNA from young abaca samples amenable to RT-qPCR and next-generation sequencing studies.