Social isolation is associated with microRNA expression changes in the visual system of poison frog tadpoles

MicroRNA (miRNA) expression in the visual system of poison frog tadpoles can be influenced by social environment, according to a recent study. Researchers manipulated the social rearing conditions of brilliant-thighed poison frog tadpoles to investigate the effect of isolation on miRNA expression in the midbrain and eyes, which are connected by the retinotectal tract.

The study found that isolated tadpoles spent less time on the dark side in a light/dark preference assay, indicating altered visually guided behavior. In a social place preference assay, group-housed tadpoles preferred a zone near a conspecific over an object control, but vision alone was not sufficient for this preference. Social rearing conditions were associated with upregulation of the non-dominant arm of miR-15-P1c_3p* in the midbrain and eyes of isolated tadpoles, and a shift in arm dosing for miR-124, a miRNA with roles in neural differentiation and plasticity.

Lastly, social isolation during development was linked to downregulation of parathyroid hormone 2 (pth2), a peptide related to social isolation and mechanosensation in other aquatic larvae. These findings contribute to the growing evidence of miRNAs' role in developmental neuroplasticity and present new signatures of the transcriptional and regulatory response to isolation.