Gene Expression Variation and Protein Evolution Among UVR-Tolerant Daphnia melanica
Year: 2026
Type: software
Abstract: Organisms that inhabit stressful environments often develop a suite of adaptive phenotypes to reduce the fitness cost in these challenging contexts. Deciphering the genetic basis of these adaptive traits is facilitated by an examination of changes in gene function and regulation across a gradient of environmental conditions. Ultraviolet radiation (UVR) is a pervasive environmental challenge that natural populations frequently encounter. Organisms living in high UVR environments manifest a variety of adaptive phenotypes to counter the deleterious effects of UVR exposure including; behavioral avoidance, protective pigmentation, and enhanced DNA repair. In our study we explored the genetic mechanisms underlying UVR tolerance in natural populations of the microcrustacean Daphnia melanica that live in high elevation ponds. In these populations of D. melanica the degree of UVR tolerance is correlated with varying UVR penetrance due to differences in dissolved organic matter (DOM) levels. Our analysis of gene expression variation highlighted a set of UVR responsive genes, and UVR responsive genes that were associated with differences in UVR tolerance. We identified three potentially locally adapted and UVR responsive genes that are known to be involved in the UVR response, inflammatory response, and light repair processes: NF-kB, mucin-2, and adrenodoxin. Differences in UVT tolerance and the expression of genes associated with DNA repair and oxidative stress occur over modest geographic distances. Our results highlight the fine-tuned adaptive responses that are possible over limited geographic or altitudinal ranges when there is a combination of strong selection and limited gene flow.
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7166385400