Dr. Robert W. Thacker of the University of Alabama at Birmingham has been awarded a grant to investigate evolutionary relationships between marine sponges in the family Dysideidae and the microbial symbionts [cyanobacteria ("blue-green algae")] and other bacteria] that live inside these sponges. Many species in the Family Dysideidae produce chemical compounds with anti-viral and anti-cancer properties. Although the porous bodies of these marine sponges can host diverse microbial communities, the role of microbial symbionts in the production of pharmaceutically active compounds remains unclear. A preliminary study by Dr. Thacker suggests that as sponges have evolved and split into distinct species, their microbial communities have evolved in tandem and are specific to each species of sponge. This study will examine several species of Dysidea and related genera from the Western Pacific, Caribbean, and Mediterranean regions. Sponge DNA sequences and microbial DNA sequences will be compared to test the hypothesis that sponges and their symbionts share parallel evolutionary histories. This study will also investigate the placement of the Family Dysideidae into either Order Dendroceratida or Order Dictyoceratida by comparing DNA sequences among members of the Dysideidae and selected sponges from the two orders. In addition, this study will test whether the production of pharmaceutically active compounds is associated with the presence or absence of specific symbionts. This research project will provide a rare, direct comparison of the evolutionary histories of sponges and their symbionts, with an immediate impact on the fields of sponge taxonomy, drug discovery, and host-symbiont coevolution. The project will also provide a greater understanding of the evolutionary histories of sponges and their symbionts, which will accelerate and enrich the search for new anti-viral and anti-cancer drugs. Increased knowledge of these host-microbe interactions will directly impact our understanding of all types of animal-microbe interactions, including those involving humans.
