Diapause in the Colorado potato beetle is characterized by sex-specific gene expression

Authors: Torson, Alex; Melicher, Dacotah; Yocum, George; Rinehart, Joseph

Submitted to: Journal of Insect Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/15/2026
Publication Date: 4/16/2026
Citation: Torson, A.S., Melicher, D.M., Yocum, G.D., Rinehart, J.P. 2026. Diapause in the Colorado potato beetle is characterized by sex-specific gene expression. Journal of Insect Physiology. https://doi.org/10.1016/j.jinsphys.2026.104990.
DOI: https://doi.org/10.1016/j.jinsphys.2026.104990

Interpretive Summary: The Colorado potato beetle is a major agricultural pest that enters dormancy to survive winter. While both male and female beetles undergo this survival strategy, it is not clear how their physiology differs during dormancy. ARS scientists in Fargo, ND used gene sequencing to compare dormant and non-dormant adult males and females. The researchers found that diapause involves much more than simply "shutting down" for winter. Instead, beetles undergo complex reprogramming, with over 10,000 genes changing their activity levels. We show that while males and females share many common diapause responses – such as reducing energy consumption and increasing stress tolerance – they also employ distinct regulatory strategies. Female beetles focus on enhanced cellular maintenance and fat mobilization, while male beetles enhance their genetic maintenance systems and protein production control. Understanding these sex-specific differences could lead to more targeted pest management strategies, potentially helping farmers better control this economically important crop pest while reducing reliance on broad-spectrum insecticides.

Technical Abstract: To cope with harsh winter conditions, many temperate insects enter diapause, a hormonally controlled dormancy characterized by developmental arrest, metabolic suppression, and enhanced stress tolerance. While diapause phenotypes are generally conserved across taxa, the underlying physiological mechanisms vary among species and life stages, with sex-specific regulation remaining poorly understood. In this study, we characterized sex-specific transcriptomic profiles of diapausing and non-diapausing adult Colorado potato beetles (Leptinotarsa decemlineata) using RNA-seq. We identified 10,060 differentially expressed transcripts, with 2,366 exhibiting concordant expression between sexes, 4,653 female-specific, 2,813 male-specific, and 228 displaying significant sex*diapause interactions. The shared transcriptional profiles revealed coordinated suppression of aerobic metabolism and robust stress tolerance. Our network analysis revealed hierarchical organization of the diapause transcriptional response through five hub modules coordinating opposing transcriptional programs. Sex-specific profiles suggest that females employ enhanced cellular maintenance strategies through spliceosome pathway enrichment and enhanced lipid mobilization capacity, while males maintain enhanced post-transcriptional control via mRNA surveillance pathways and comprehensive genomic maintenance systems. Sex*diapause interactions revealed precise modulation of master regulatory pathways, with opposing growth-regulation signaling strategies. We conclude that diapause involves differential regulation of a core set of sex-independent processes as well as robust, sex-specific regulatory mechanisms that enable coordinated reprogramming rather than simple metabolic shutdown.