Meeting Abstract
22.4 Monday, Jan. 4 Expression profiling coral responses to thermal stress and settlement cues using RNA-Seq MEYER, E*; MATZ, MV; University of Texas, Austin; University of Texas, Austin EliMeyer@mail.utexas.edu
Quantitative transcriptome analysis using next-generation sequencing methods (RNA-Seq) has become an important tool in functional genomics, but this approach has mostly been limited to a handful of model systems with sequenced genomes. Our recent sequencing and annotation of the transcriptome for a reef-building coral (Acropora millepora) has provided a set of reference sequences to allow RNA-Seq expression profiling for this species. We have developed a simple method for cDNA sample preparation for sequencing using SOLiD, a short-read technology with massive throughput (10s of millions of reads). Using this platform, we characterized the changes in global gene expression profiles of coral larvae in response to elevated temperatures and settlement cues. About one million reads from each sample were mapped to the transcriptome, providing quantitative estimates of expression levels for more than 10,000 genes in each treatment. These data revealed reproducible differential expression for hundreds of genes in response to a natural settlement cue and an artificial peptide inducer of metamorphosis, identifying candidates that include putative receptors and morphogens. Similarly, reproducible differences in expression profiles during short- or long-term thermal stress identified novel candidates for this widely-studied process. The changes in expression levels of selected candidates were validated by qPCR, confirming the utility of RNA-Seq for expression profiling in this system and supporting the involvement of these candidate genes in coral responses to thermal stresses and settlement cues. Because these traits are likely to be adaptively important for corals faced with increasing sea surface temperatures, these findings provide important new insights into the potential for survival and adaptation of corals during climate change.
