Data from: An initial comparative genomic autopsy of wasting disease in sea stars

Beginning in 2013, sea stars throughout the Eastern North Pacific were
decimated by wasting disease, also known as ‘asteroid idiopathic wasting
syndrome’ (AIWS) due to its elusive etiology. The geographic extent and
taxonomic scale of AIWS meant events leading up to the outbreak were
heterogeneous, multifaceted, and oftentimes unobserved; progression from
morbidity to death was rapid, leaving few tell-tale symptoms. Here we take
a forensic genomic approach to discover candidate genes that may help
explain sea star wasting syndrome. We report the first genome and
annotation for P. ochraceus, along with differential gene expression (DGE)
analyses in four size classes, three tissue types, and in symptomatic and
asymptomatic individuals. We integrate nucleotide polymorphisms associated
with survivors of the wasting disease outbreak, DGE associated with
temperature treatments in P. ochraceus, and DGE associated with wasting in
another asteroid Pycnopodia helianthoides. In P. ochraceus, we find DGE
across all tissues, among size classes, and between asymptomatic and
symptomatic individuals; the strongest wasting-associated DGE signal is in
pyloric caecum. We also find previously identified outlier loci co-occur
with differentially expressed genes. In cross-species comparisons of
symptomatic and asymptomatic individuals, consistent responses distinguish
genes associated with invertebrate innate immunity and chemical defense,
consistent with context-dependent stress responses, defensive apoptosis,
and tissue degradation. Our analyses thus highlight genomic constituents
that may link suspected environmental drivers (elevated temperature) with
intrinsic differences among individuals (age/size, alleles associated with
susceptibility) that elicit organismal responses (e.g. coelomocyte
proliferation) and manifest as sea star wasting mass mortality.