RNAlater® Solution

Ecologists are interested in understanding environmental factors that support plankton growth in aquatic ecosystems. This requires the processing and analysis of a large number of samples with low RNA and DNA content for estimating growth and nutritional conditions for these small organisms. Successful preservation and processing of collected samples is therefore critical. However, deep freezing in liquid nitrogen is not convenient for aquatic samples collected on oceanographic cruises and remote field studies. Dr. Gorokhava tested whether RNAlater® Tissue Collection: RNA Stabilization Solution could be used for sample preservation, instead of deep freezing for preserving nucleic acids in brine shrimp nauplii* (Artemia salina). Newly hatched shrimp nauplii were stored at (1) -80°C, (2) in RNA later Solution at 5°C, or (3) in RNA later Solution at room temperature.

Total cellular RNA and DNA were quantified in individual nauplii using a fluorometric assay. RNA and DNA yields were subsequently compared with control samples (fresh animals assayed immediately after hatching) and among preservation treatments to determine the longterm effects of different sample storage techniques. Nucleic acid quantities were determined for each preservation treatment after one, two, four, and eight months. For both RNA and DNA yields, shrimp samples stored in RNA later Solution at 5°C were equivalent to those stored at -80°C for at least four months after preservation.

The study concluded that RNA later Solution successfully preserved both RNA and DNA for up to one month at room temperature, and up to four months at 5°C, suggesting that RNA later Solution provides reliable sample preservation immediately upon collection. This result demonstrates that use of RNA later Solution for extended storage is equal to the established gold-standard of storage at -80°C. Also, with small organisms RNA later Solution provides the flexibility of storing them intact.

*nauplii is a developmental stage in brine shrimp.