RT Journal Article SR Electronic T1 Comparison of Methods for Isolating High-Quality RNA from Leaves of Grapevine JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP 400 OP 406 DO 10.5344/ajev.2005.56.4.400 VO 56 IS 4 A1 Elizabeth A.R. Tattersall A1 Ali Ergul A1 Fadi AlKayal A1 Laurent DeLuc A1 John C. Cushman A1 Grant R. Cramer YR 2005 UL http://www.ajevonline.org/content/56/4/400.abstract AB High concentrations of polyphenols and polysaccharides make it challenging to extract high-quality RNA from grape organs. To determine an optimal protocol for grape leaves, 15 different methods of RNA extraction were evaluated based on cost, time to complete the extraction, and quality of the RNA isolated. The addition of specific compounds to the extraction buffer to remove polyphenols and polysaccharides is often critical for downstream applications such as polymerase chain reaction (PCR) and microarray hybridization. RNA quality was assessed using spectrophotometric methods, formaldehyde-agarose gel electrophoresis, reverse transcription (RT)-PCR reactions, and Agilent 2100 Bioanalyzer. Large differences in RNA yield and quality among protocols were found. Some protocols that are commonly used for other species did not yield usable RNA from grapevine leaves. The optimum methods were Tris-lithium chloride, which, while relatively time-consuming, gave consistently high yields of quality RNA at very low cost and was suitable for PCR and microarray hybridization, and RNeasy Midi + polyethylene glycol, which rapidly provided high-quality RNA, but with lower yields.