Overview

• The University of Tokyo team developed a system using hyperactive insertion sequences to rapidly induce large-scale bacterial genome changes.
• In just ten weeks, engineered E. coli exhibited 25 new insertion events and genome size changes exceeding 5%, mimicking decades of natural evolution.
• The experiments uncovered a dynamic balance between frequent small deletions and rare large duplications, challenging prior assumptions about genome reduction.
• Researchers observed the formation of composite transposons, offering clues about the evolution and diversification of complex mobile genetic elements.
• Future studies aim to explore how cooperative behaviors and biological complexity emerge under controlled evolutionary conditions.