Comparison of methods for extracting high-throughput sequencing RNA from Korean pine seeds

Korean pine （Pinus koraiensis Sieb. et Zucc.） is an ecologically and economically important tree species in East Asia. Molecular studies of seed development of this species are limited due to the lack of effective RNA extraction protocols. This study aimed to obtain an effec- tive method to extract high-quality RNA from Korean pine seeds. The TRIzol kit and CTAB methods were used to extract the total RNA from Korean pine seeds at different developmental stages. The bands of RNA extracted by CTAB were not clear, whereas the bands of RNA extracted by the TRIzol kit were brighter and clearer, indicating higher quality and integrity of the RNA products extracted by the TRIzol kit. The 28S rRNA band was approximately 1.5- to 2-fold brighter than the 18S rRNA band on the agarose gel electrophoresis. The absorbance value A 260/280 was 1.8-2.0, and the absorbance value A 260/230 was 〉1.9. The Bioanalyzer RNA integrity results showed that the RNA integrity number of the RNA extracted using the TR/zol kit was acceptable for high-throughputsequencing. Therefore, the total RNA extracted using the TRIzol kit method can be used for high-throughput sequencing and other molecular biology experiments.