A sociogenomic study of fire ants in PLOS Genetics suggests the insect's gene expression shifts more dramatically in response to its social environment than its social rank. Using a whole-genome array, a team from the US and Switzerland assessed gene expression patterns in Solenopsis invicta fire ants as they established new colonies. By comparing expression profiles in ants from colonies with just one mated queen or from colonies where multiple mated queens vie for colony control, researchers got clues about genes involved in the insect's behavioral roles as well as the circumstances affecting their expression. Based on their findings, the study's authors concluded that "social environment … is a much greater driver of gene expression changes than social rank itself, suggesting that social environment, and not reproductive state, is a key regulator of gene expression, physiology, and ultimately, behavior."
In PLOS One, researchers from Finland, the UK, and the US report on findings from a genome-wide association study of hereditary glaucoma in dogs. The team focused on the Dandie Dinmont Terrier, a breed prone to a form of progressive, adult-onset glaucoma that resembles primary closed-angle glaucoma in humans. By genotyping 23 affected and 23 unaffected dogs using Illumina's Canine SNP20 chip, authors of the study picked up a chromosome 8 locus with apparent ties to glaucoma risk in the terrier. And fine-mapping experiments in a larger set of cases and controls from the same breed helped the study's authors narrow in on the most significantly associated SNPs at that locus, which corresponds to a region of the human chromosome 14 housing genes previously implicated in other forms of glaucoma.
The University of Vienna's Matthias Horn and colleagues delve into the details of Chlamydiae bacteria's infectivity by looking at metabolomic profiles in an extracellular form of Protochlamydia amoebophila, an environmental Chlamydiae species that acts as a symbiont to amoebas. As they reported in PLOS Pathogens, the researchers used a combination of methods — from mass spec approaches to fluorescence microscopy assays — to take note of metabolic compounds produced during P. amoebophila's infective, spore-like stage. Those elementary body forms of P. amoebophila accomplish metabolic feats that are host independent, they found, highlighting the potential importance of this developmental phase in the bug's broader infective ability.