Presentation Detail

Ecological Genetics and/or Genomics

Gleason, Lani [1], Burton, Ronald S. [2].

Using RNA-Seq to Investigate Local Adaptation to Heat Stress in the Marine Snail Chlorostoma (formerly Tegula) funebralis.

Southern populations of the marine snail Chlorostoma (formerly Tegula) funebralis generally occupy warmer climates and higher intertidal heights (due to higher predation pressure) than Northern populations. Therefore, Southern populations are exposed to high air temperatures during low tides more frequently than Northern populations. Previous phenotypic work has shown that Southern populations are more tolerant of heat stress than Northern populations. We hypothesize this difference in heat stress tolerance is due in part to differential gene expression; we expect that a Southern population will show a different transcriptomic response to heat stress than a Northern population. To test this hypothesis, we exposed one Southern and one Northern population of C. funebralis (both common-garden acclimated) to a heat stress representative of natural low tide conditions and then performed RNA-Seq using Illumina technology. Four total cDNA libraries were obtained after the simulated heat stress, along with nonstressed control treatments. Gene-expression patterns after stress were dominated by classical heatshock proteins in both populations, but Principal Components Analysis (PCA) revealed the transcription profiles were different in the two populations. For instance, heat shock proteins (HSPs) were upregulated to different degrees in the two populations, with the Northern population upregulating several HSPs significantly higher than the Southern population following heat stress. Furthermore,enrichment analysis on the control versus treatment differentially expressed genes in the two populations revealed that several different GO functional gene categories were significantly enriched (Fisher̢۪s exact test) in the Northern but not in the Southern population, and vice versa. These analyses indicate that the difference in thermal tolerance, at least between these particular Northern and Southern populations, indeed is due in part to different gene-expression patterns.

1 - Scripps Institution of Oceanography, Marine Biology Research Division, 8750 Biological Grade, Hubbs Hall, Room 2330, La Jolla, CA, 92037, United States
2 - Scripps Institution of Oceanography, Marine Biology Research Division, 8750 Biological Grade, Hubbs Hall, Room 2140, La Jolla, CA, 92037, United States

Keywords:
local adaptation
heat stress
marine mollusk
RNA-seq
rocky intertidal.

Presentation Type: Regular Oral Presentation
Session: 38
Location: Cotton C/Snowbird Center
Date: Saturday, June 22nd, 2013
Time: 3:30 PM
Number: 38001
Abstract ID:242
Candidate for Awards:W.D. Hamilton Award for Outstanding Student Presentation