Summary: Eur. J. Phycol. (2006), 41: 97­104
Simple and rapid RNA extraction from freeze-dried tissue
of brown algae and seagrasses
GARETH PEARSON, ASUNCION LAGO-LESTON, MARTA VALENTE AND ESTER SERRA~ O
CCMAR, CIMAR/Laborato´rio Associado, F.C.M.A., Universidade do Algarve, Gambelas, 8005­139 Faro, Portugal
(Received 25 July 2005; accepted 29 November 2005)
An inexpensive and rapid RNA extraction protocol for brown algae and seagrasses is presented, based on homogenization
in a simple CTAB buffer and selective precipitation of RNA with lithium chloride. The protocol avoids the use of toxic
chaotropic agents and phenol; high concentrations of dithiothreitol are used to inhibit RNase activity and to prevent oxidative
cross-linking of nucleic acids by phenolics. A relatively high throughput of about 100 samples in 24 h can be achieved for,
for example, Northern analysis. Yields of 50­200 mg gÀ1
fresh weight are comparable with those obtained for higher plants
using commercially available kits. Tests of the extraction procedure demonstrate that high quality, intact RNA can be
obtained from a variety of lyophilized brown algal tissues, even after prolonged storage at room temperature. Lyophilization
is therefore suggested as an alternative to freezing tissue at À70
C to À80
C. The RNA obtained was used directly in several
downstream applications to detect Fucus plastid-encoded transcripts by RNA-labelling, RT-PCR and Northern analysis.
Key words: brown algae, Fucus, lyophilization, plastid gene expression, rbcL, RNA extraction, seagrass
Introduction

Source: Alberto, Filipe - Centro de Ciencias do Mar, Universidade do Algarve

Collections: Environmental Sciences and Ecology; Biology and Medicine