Sleeping upside-down: Knockdown of a sleep-associated gene induces daytime sleep in the jellyfish .

The conservation of sleep among diverse animals provides clear evidence for its physiological importance, but the extent of its regulatory conservation is unknown. The upside-down jellyfish sleeps, and this behavior is controlled by radially spaced marginal ganglia. After defining a sleep-wake threshold, we compared gene expression profiles of ganglia from animals deprived of sleep and found differential expression in many sleep-related genes including GABAergic, melatonergic, and cholinergic receptors.

Cassiopea xamachana microbiome across anatomy, development, and geography.

The upside-down jellyfish holobiont, Cassiopea xamachana, is a useful model system for tri-partite interactions between the cnidarian host, the photosymbiont, and the bacterial microbiome. While the interaction between the host and photosymbiont has been well studied, less is understood of the associated bacterial community. To date, the bacterial microbiome of wild C.

The microbiome of a Pacific moon jellyfish Aurelia coerulea.

The impact of microbiome in animal physiology is well appreciated, but characterization of animal-microbe symbiosis in marine environments remains a growing need. This study characterizes the microbial communities associated with the moon jellyfish Aurelia coerulea, first isolated from the East Pacific Ocean and has since been utilized as an experimental system. We find that the microbiome of this Pacific Aurelia culture is dominated by two taxa, a Mollicutes and Rickettsiales.

Comparative Genomic Insights into Bacterial Induction of Larval Settlement and Metamorphosis in the Upside-Down Jellyfish .

Bacteria are important mediators of the larval transition from pelagic to benthic environments for marine organisms. Bacteria can therefore dictate species distribution and success of an individual. Despite the importance of marine bacteria to animal ecology, the identity of inductive microbes for many invertebrates are unknown.

Box, stalked, and upside-down? Draft genomes from diverse jellyfish (Cnidaria, Acraspeda) lineages: Alatina alata (Cubozoa), Calvadosia cruxmelitensis (Staurozoa), and Cassiopea xamachana (Scyphozoa).

Background: Anthozoa, Endocnidozoa, and Medusozoa are the 3 major clades of Cnidaria. Medusozoa is further divided into 4 clades, Hydrozoa, Staurozoa, Cubozoa, and Scyphozoa-the latter 3 lineages make up the clade Acraspeda. Acraspeda encompasses extraordinary diversity in terms of life history, numerous nuisance species, taxa with complex eyes rivaling other animals, and some of the most venomous organisms on the planet.

Purging deleterious mutations under self fertilization: paradoxical recovery in fitness with increasing mutation rate in Caenorhabditis elegans.

Background: The accumulation of deleterious mutations can drastically reduce population mean fitness. Self-fertilization is thought to be an effective means of purging deleterious mutations. However, widespread linkage disequilibrium generated and maintained by self-fertilization is predicted to reduce the efficacy of purging when mutations are present at multiple loci.