Chloroplast sunscreening by protein condensates confers high-light tolerance.

MBS1 condensates in rice chloroplasts provide high-light tolerance by acting as a sunscreening mechanism, with overexpression increasing yield under stress conditions.

• Why it matters: Understanding how chloroplasts rapidly respond to singlet oxygen is crucial for improving plant resilience to high-light stress, which is intensified by climate change.
• What they did: Researchers identified MBS1, a conserved protein with a zinc-finger domain, that undergoes phase transition from liquid-like droplets to condensates in response to high light, attenuating light penetration.
• The result: Overexpressing MBS1 in rice enhances high-light tolerance and yield in field trials, suggesting that MBS1 condensates could be exploited to improve crop performance under environmental stress.