Salgado, A.; Vieiralves, T.; Lamarão, F.R.M.; Assumpção, L.L.M.; Gomes, D.; Jascone, L.; Valadão, A.L.; Albano, R.M.; Lôbo-Hajdu, G. (2007). Field preservation and optimization of a DNA extraction method for Porifera. pp 555-560 in: Custódio MR, Lôbo-Hajdu G, Hajdu E, Muricy G (eds) Porifera Research. Biodiversity, Innovation and Sustainability. Livros de Museu Nacional 28, Rio de Janeiro.
Field preservation and optimization of a DNA extraction method for Porifera. pp 555-560 <i>in</i>: Custódio MR, Lôbo-Hajdu G, Hajdu E, Muricy G (eds) Porifera Research. Biodiversity, Innovation and Sustainability. Livros de Museu Nacional 28, Rio de Janeiro.
Publication
Proceedings of the 7th International Sponge Conference, Buzios 2006
Available for editors
The small number of molecular studies on lower invertebrates may be due to a limited availability of fresh or properly preserved biological material. Specimens collected and preserved in different fixatives can influence the quality of the extracted DNA. Variables such as the type of fixative, time of storage, and extraction protocol are critical for obtaining DNA in sufficient quantity and of good quality. This work evaluates the efficiency of six different field fixatives and the most effective DNA extraction protocol for marine sponges. Sponges were collected and preserved in one of the following: 1) 96% ethanol, 2) 70% ethanol, 3) dry-ice, 4) air-dried, 5) lyses buffer with guanidine hydrochloride (LBWGH), or 6) silica gel. Genomic DNA was extracted by one of four different protocols: lyses buffer with proteinase K, cetyl trimethyl ammonium bromide (CTAB), guanidine hydrochloride or DNAzol®. The quality of the DNA obtained was determined with scores of the DNA degradation level. Our results showed that high molecular weight DNA was seen with all six fixatives albeit with a great variation in DNA quality. Based on gel analysis, the most effective preservation methods, both in quality and quantity, were dry ice, silica gel and LBWGH. Regarding the DNA extraction procedures, CTAB, LBWGH and the DNAzol® methods produced high quality genomic DNA. However, considering the cost-benefit ratio of the methods for the processing of a large number of samples, a short term preservation in combination with extraction with LBWGH is the best protocol among the techniques tested here.
