Insect cold hardiness is associated with substantial metabolic rate suppression, often including developmental diapause as well as metabolic suppression imposed by freezing and freeze-associated oxygen limitation. MicroRNAs, small non-coding transcripts that bind to mRNA, are known modulators of hypometabolism in freeze tolerant insects. To further contribute to the growing signature of stress-responsive miRNAs, this study amplified and quantified changes in the expression levels of four microRNA species, miR-8, miR-9, miR-92b and miR-277, in response to freezing or anoxia exposures of freeze tolerant gall fly larvae, Eurosta solidaginis. MiR-92b levels were significantly elevated by 1.57-fold in frozen E. solidaginis at -15 °C as compared with 5 °C controls, whereas miR-92b levels were significantly reduced in anoxic E. solidaginis to levels that were 0.77-fold as compared with larvae held under normoxic conditions. The other miRNAs investigated showed no significant changes in stressed larvae. These data demonstrate differential miR-92b expression in frozen/anoxic versus control insect larvae and position this miRNA as a stress responsive marker in this model insect.

Additional Metadata
Keywords Eurosta solidaginis, Freeze tolerance, MicroRNAs, Translational regulation
Persistent URL dx.doi.org/10.1016/j.cryobiol.2015.05.002
Journal Cryobiology
Citation
Lyons, P.J. (Pierre J.), Storey, K, & Morin, P.J. (Pier Jr.). (2015). Expression of miRNAs in response to freezing and anoxia stresses in the freeze tolerant fly Eurosta solidaginis. Cryobiology, 71(1), 97–102. doi:10.1016/j.cryobiol.2015.05.002