Meeting Abstract
We sequenced the genome of the herbivorous monkeyface prickleback (Cebidichthys violaceus) along with transcriptomes from nine tissues to gain insight into how this fish species thrives on an herbivorous diet in a heterogeneous intertidal habitat. The draft genome of C. violaceus was sequenced using Illumina and Pacific Biosciences sequencing technologies, with a size estimation of 656 Mb and 29,525 genes were identified via ab initio. With the nine tissue transcriptomes, we generated heatmaps of differentially expressed genes to locate genes associated with digestion and metabolism. With the transcriptome profiles of the liver, pyloric caeca, proximal and middle intestines of C. violaceus, we identified differentially expressed genes (DEG) that are associated with ketogenic metabolism, which represent the downstream pathways allowing this fish to utilize the short-chain fatty acids generated by microbial symbionts within their distal intestines. In addition, we identified four gene copies (haploid) of Bile salt-activating lipase (BAL) genes within the C. violaceus genome (most other fishes appear to only have two BAL gene copies), which coincides with elevated lipolytic activity in the guts of this fish. BAL orthologs (as well as other genes involved in digestion and metabolism) and gene copy numbers were identified in other teleost fishes to make stronger inferences about digestion and metabolism. Overall, the draft genome of C. violaceus will give us a better understanding of the evolutionary processes of dietary specialization and can lead to hypothesis formation regarding adaptations to intertidal habitats.
