How Plants Cope with High Temperatures

Scientists have long known that the surfaces of plant leaves are covered with many tiny stomata. When temperatures rise, these microscopic pores "open up" to allow water to evaporate, thereby carrying away heat, much like how sweating cools humans down. However, the molecular regulatory mechanism behind stomata, the plant's "radiator," has remained an unsolved mystery.

At the core of this pathway is a protein called ubiquitin-specific protease 24 (UBP24). They found that when high temperatures strike, kinases within the plant "awaken" UBP24, altering its molecular charge and making it more stable. In this more stable state, UBP24 helps to "protect" and activate other proteins involved in maintaining stomatal opening, keeping the plant's evaporative cooling system active during heat stress.

In layman's terms, UBP24 acts like a sensitive thermostat on an "air conditioner." A similar story is not only unfolding in plants. Scientists also discovered that a related protein in brewer's yeast relies on a similar principle to cope with heat stress.

Yeast and plants belong to different species, lead vastly different lifestyles, and are separated by hundreds of millions of years of evolutionary divergence, yet they employ similar "heat dissipation logic" at the cellular level.