CTAB Protocol for Obtaining High-Quality Total RNA from Hibiscus rosa-sinensis and Other Related Plants of the Family Malvaceae

ACS Omega. 2024 Apr 22;9(18):20359-20367. doi: 10.1021/acsomega.4c00877. eCollection 2024 May 7.

Abstract

Malvaceae family, also known as the Mallow family, is a family of flowering plants containing Hibiscus rosa-sinensis and other plants of high medicinal value. This study focuses on the challenges associated with high-quality RNA extraction from Hibiscus rosa-sinensis and its related plants characterized by high levels of mucilage and phenolic compounds in their tissues. High mucilage and secondary metabolite content pose obstacles in obtaining high-quality RNA, negatively impacting downstream applications, such as gene expression analysis. Our research aimed to develop an efficient RNA extraction method tailored to the unique characteristics of Malvaceae family plants especially Hibiscus rosa-sinensis. Through the substitution of NaCl with KCl, a crucial component of the CTAB buffer, our methodology successfully addressed the challenges posed by high mucilage and phenolic compound levels. This modification led to a significant reduction in sample viscosity, which is because of the high mucilage in these plants. Our modified CTAB extraction method yielded significantly more RNA with higher purity than the conventional CTAB methods alone. The extracted RNA was largely intact, as indicated by 28S/18S ratios and RIN values, yielding high-quality RNA with improved purity suggested by the 260/280 and 260/230 ratios. The proposed approach not only serves as a solution to the specific challenges encountered in Hibiscus rosa-sinensis but also holds promise for broader applications across different plants within the family.