Comparison of different methods for total RNA extraction from sclerotia of Rhizoctonia solani

Background Rhizoctonia solani (teleomorph: Thanatephorus cucumeris) is one of the most important pathogens of rice (Oryza sativa L.) that causes severe yield losses in all rice-growing regions. Sclerotia, formed from the aggregation of hyphae, are important structures in the life cycles of R. solani and contain a large quantity of polysaccharides, lipids, proteins and pigments. In order to extract high-quality total RNA from the sclerotia of R. solani, five methods, including E.Z.N.A.™ Fungal RNA Kit, sodium dodecyl sulfate (SDS)-sodium borate, SDS-polyvinylpyrrolidone (PVP), guanidinium thiocyanate (GTC) and modified Trizol, were compared in this study. Results The electrophoresis results showed that it failed to extract total RNA from the sclerotia using modified Trizol method, whereas it could extract total RNA from the sclerotia using other four methods. Further experiments confirmed that the total RNA extracted using SDS-sodium borate, SDS-PVP and E.Z.N.A.™ Fungal RNA Kit methods could be used for RT-PCR of the specific amplification of GAPDH gene fragments, and that extracted using GTC method did not fulfill the requirement for above-mentioned RT-PCR experiment. Conclusion It is concluded that SDS-sodium borate and SDS-PVP methods were the better ones for the extraction of high-quality total RNA that could be used for future gene cloning and expression studies, whereas E.Z.N.A.™ Fungal RNA Kit was not taken into consideration when deal with a large quantity of samples because it is expensive and relatively low yield.

A method with TRIzol~ reagent and liquid nitrogen to extract high-quality RNA from rat pancreas / 西安交通大学学报(医学版)

Objective To establish a quick,economical and reproducible method for high-quality RNA extraction from pancreas.Methods We utilized TRIzol Reagent and liquid nitrogen to isolate total RNA from the rat pancreas.The RNA quality was determined by detection of its content and optic density(A) at 260/280nm,and electrophoresis in 1% non-denatured agarose gel.Then reverse transcription-polymerase chain reaction(RT-PCR) was performed to detect expression of the pancreas-specific genes.Results The content of the total RNA extracted from the rat pancreas reached 3-6?g/mg pancreatic tissues,and A260/280 ratio was 1.75-1.89.Electrophoresis of the total RNA showed 28S and 18S rRNA bands with clear smear between them.The RT-PCR products of pancreas-specific genes including insulin 1,glucagon,?-amylase and housekeeping gene ?-actin all exhibited clear bands on 1% agarose gel,which were located in the expected positions,respectively.Conclusion These results suggest that we have successfully isolated the high-quality and intact RNA from the rat pancreas with TRIzol Reagent and liquid nitrogen.The extracted total RNA can be used in RT-PCR for pancreatic gene expression.