On obliterating the initial barriers of polyploidy: insights from Nasonia neopolyploids

Summary

Whole genome duplication (polyploidy) complicates cellular processes but drives eukaryotic evolution. Studying polyploid adaptation requires a system where polyploidy is inducible and sustainable over generations—challenging in animals due to first-generation lethality. The parasitoid wasp Nasonia vitripennis presents an ideal model: polyploidy can be induced via sex-determination gene silencing or colchicine treatment, and Nasonia's rapid generations enable experimental evolution studies. Strong phenotypic variation aids in identifying mechanisms differentiating evolutionary dead ends from success. Decades of Nasonia research provide extensive -omics datasets, facilitating studies on polyploid genomic and transcriptomic effects. Inbred and outbred lines allow controlled experiments, while interspecific crosses enable direct comparisons of autopolyploidy and allopolyploidy. Additionally, Nasonia offers a platform for exploring polyploidy’s potential in biological control.-Polyploidy is increasingly recognized as an evolutionary force in animals, yet its transcriptomic effects remain largely unknown. This study presents an RNA-seq atlas of Nasonia vitripennis, profiling three neopolyploid lines and a long-standing polyploid line with diploid males and triploid females. By analyzing head and abdominal tissues across generations (F2, F3, F14, F15), we identified sex- and tissue-specific transcriptomic signatures. Abdominal tissues exhibited sex-specific differences, while early-generation triploids showed gene downregulation, shifting to more nuanced changes in later generations—potentially linked to metabolic efficiency and reproductive success. Males showed enrichment in sensory perception pathways, whereas females exhibited enrichment in ribosomal and mitochondrial functions. This atlas provides key insights into polyploid transcriptional responses in insects, guiding further genomic investigations.