Genetic Signature of Resistance to White Band Disease in the Caribbean Staghorn Coral <i>Acropora cervicornis</i>

<div><p>Coral reefs are declining worldwide due to multiple factors including rising sea surface temperature, ocean acidification, and disease outbreaks. Over the last 30 years, White Band Disease (WBD) alone has killed up to 95% of the Caribbean`s dominant shallow-water corals—the staghorn coral <i>Acropora cervicornis</i> and the elkhorn coral <i>A</i>. <i>palmata</i>. Both corals are now listed on the US Endangered Species Act, and while their recovery has been slow, recent transmission surveys indicate that more than 5% of staghorn corals are disease resistant. Here we compared transcriptome-wide gene expression between resistant and susceptible staghorn corals exposed to WBD using <i>in situ</i> transmission assays. We identified constitutive gene expression differences underlying disease resistance that are independent from the immune response associated with disease exposure. Genes involved in RNA interference-mediated gene silencing, including Argonaute were up-regulated in resistant corals, whereas heat shock proteins (HSPs) were down-regulated. Up-regulation of Argonaute proteins indicates that post-transcriptional gene silencing plays a key, but previously unsuspected role in coral immunity and disease resistance. Constitutive expression of HSPs has been linked to thermal resilience in other <i>Acropora</i> corals, suggesting that the down-regulation of HSPs in disease resistant staghorn corals may confer a dual benefit of thermal resilience.</p></div

PdamT5JA_Pst1.fq

Pocillopora damicornis - Type 5 - Japan - Digested with Pst1, single-end RADSe

Colony 3 Day Tip Illumina Reads

Demultiplexed Illumina read data for Colony 3, daytime tip sample of Acropora cervicornis

Gene expression analysis of resistant (R) and susceptible (S) corals exposed to allogeneic tissue and active White Band Disease (WBD).

<p>Clustered heatmap for gene expression of the 35 annotated differentially expressed genes that differ between resistant (R) and susceptible (S) corals exposed to WBD grafts (D), healthy grafts (H) and unexposed (no graft) controls (C). Hierarchical clustering was performed using Pearson correlation metrics and indicates similarity between the different samples (columns), with <b>resistant and susceptible samples forming different clusters.</b> Red corresponds to up-regulated genes, blue indicates down-regulation. The expression level for each transcript was calculated as log2 fold change of normalized count data. Asterisks indicate transcripts that were DE in both factors (resistance + exposure). See also <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146636#pone.0146636.s001" target="_blank">S1 Table</a>.</p

Colony 3 Day Base Illumina Reads

Demultiplexed Illumina read data for Colony 3, daytime base sample of Acropora cervicornis

PdamT1P_Pst1

Pocillopora damicornis - Type 1 - Panama - Digested with Pst1, single-end RADSeq

Colony 3 Night Tip Illumina Reads

Demultiplexed Illumina read data for Colony 3, nighttime tip sample of Acropora cervicornis

Colony 1 Day Tip Illumina Reads

Demultiplexed Illumina read data for Colony 1, daytime tip sample of Acropora cervicornis

PdamT5TU_Pst1.fq

Pocillopora damicornis - Type 5 - French Polynesia, Tuamotus - Digested with Pst1, single-end RADSe

Colony 3 Night Base Illumina Reads

Demultiplexed Illumina read data for Colony 3, nighttime base sample of Acropora cervicornis