Molecular regurgitate analysis: A technique to elucidate deep sea gastropod diet

• Main Authors: Heralde, Francisco M., III, Astilla, Mary Anne Q., Santos, Ameurfina D., Concepcion, Gisela P., Olivera, Baldomero M., Lluisma, Arturo O.
• Format: text
• Published: Animo Repository 2007
• Subjects: Gastropoda—Food; Biology
• Online Access: https://animorepository.dlsu.edu.ph/faculty_research/6852
• Institution: De La Salle University

Elucidating the diet of an organism is one of the major concerns of an ecologist as it establishes the relationship of the organism to its environment, more importantly its survival. As such various techniques for feeding ecology studies have been devised; among them are filed observations, feeding experiments, gut content analysis and faecal analysis (Duda et al. 2001, Shimek 1983). The limitation of these techniques becomes apparent when organisms like deep sea gastropods are under study. These marine snails particularly the turrids, while reported to be polychaete feeders, are difficult to observe as they may dwell in deep waters; are slow feeders; they could be nocturnal; and perform their hunting activities in th substratum (Olivera 2005, Shimek 1983). A technique is developed to determine the diet of deep sea gastropod. This involves collection of tissues freshly regurgitated by the snails, genomic DNA extraction from the tissues, and amplification of selected gene marker, followed by cloning, DNA sequencing and BLAST (basic local alignment search tool) search of the sequence in the Gnebank database. This technique which is a modification of gut analysis is applied in one species of turrid snail Gemmula diomedea (Powell 1964) using mitochrondial cytochrome oxidase 1 (mtCO1) as the gene marker. We call this technique molecular regurgitate analysis. Our choice of mtCO1 has been based on its remarkable features as a protein coding gene that is able to tolerate mutation, its utility as a DNA barcode for individual species and the extensive polychaete mtCO1 sequence database in Genbak where we can compare our sequences.