Site-specific recombination and purifying selection influence Cry toxin formation and specialization.
Site-specific recombination by XerCD drives Cry toxin evolution, leading to host specialization through purifying selection of hybrid toxins.
- Why it matters: Understanding how Cry toxins evolve in nature is crucial for improving bioinsecticide design and managing pest resistance, yet existing models are based only on lab experiments.
- What they did: The study analyzed all available Cry sequences to reveal that XerCD-mediated site-specific recombination at domain borders facilitates domain shuffling, followed by selection favoring specialized hybrids.
- The result: This mechanism explains how Cry toxins diversify and adapt to specific hosts in nature, enabling targeted bioinsecticide development and better pest control strategies.