In Science this week, a Rockefeller University team publishes a study identifying a single gene — one associated with insulin signaling — with an oversized role in the evolution of eusociality in ants. The investigators performed a brain transcriptomics screen in different types of ants across species with different reproductive strategies. They found that the gene insulin-like peptide 2 (ilp2) is always up-regulated in reproductive ants, likely because they are better nourished versus workers. Meanwhile, in clonal raider ants — a species with a weakly defined division of labor — the presence of larvae reduced ilp2 expression. By increasing levels of ilp2, a stable division between worker and queen could be established. "These findings suggest a simple model for the origin of ant eusociality via nutritionally determined reproductive asymmetries potentially amplified by larval signals," the researchers conclude.
And in Science Translational Medicine, a group led by National Institutes of Health scientists report transcriptomic data showing how wounds in the mouth heal faster than wounds to other parts of the body. In their study, the researchers induced wounds in the mouths and to the skin of 30 healthy volunteers, collecting and comparing biopsies of both sites at different time points over the following six days. RNA sequencing revealed unique patterns of gene expression linked to epithelial cell differentiation and inflammatory responses, as well as higher expression of the transcription factors SOX2, PITX1, and PITX2, in the oral samples. Notably, SOX2 and PITX1 transcriptional function can reprogram skin keratinocytes to increase cell migration and improve wound resolution in vivo. The findings highlight "fundamental global mechanisms of inflammation and repair in humans that will serve as an invaluable resource, providing insights into therapeutic targeting of chronic and non-healing wounds," the authors state.