The tissue-specific DNA repair mechanisms and adaptive evolution in silkworm

How organisms balance genetic stability with environmental adaptability remains a fundamental question in evolutionary biology. Using the silkworm, we investigated how genomes reconcile these competing demands. Through spatiotemporal genomic analysis of 121 individuals, we discovered three compensatory mechanisms: 1) Gonads prioritize DNA repair to protect germline integrity, 2) Developmental transitions employ tissue-specific copy number variations enabling dosage-controlled tissue remodeling, and 3) non-coding regions tolerate mutations while maintaining functional constraints on coding sequences. Notably, paralogous gene clusters showed concentrated variation in membrane transport pathways, suggesting reservoirs for adaptive innovation. Our findings demonstrate that silkworms resolve the stability-plasticity paradox through developmental stage-specific mutation management, safeguarding germline fidelity while permitting somatic evolution. This establishes metamorphosing insects as models for studying adaptive genome dynamics in rapidly developing eukaryotes.