The impact of heat stress on the proteome of crop species

Heat stress impairs plant growth and reproduction. A future climate where more extreme heating events are accompanied by drought and higher atmospheric CO₂ concentrations will exacerbate heat stress considering such factors will reduce stomatal conductance, reducing transpiration-dependent evaporative cooling, leading to even higher leaf temperatures. Understanding the impact of heat on crops is therefore of paramount importance when factoring in future climate scenarios. The use of proteomic techniques will enable the mechanisms by which crops can withstand the detrimental impacts of heat to be further elucidated. The proteomic literature tells us that a wide range of physiological processes will be affected by heat, including photosynthesis, respiration and energy metabolism. Certain proteins are particularly responsive to heat including Rubisco and its chaperone partner Rubisco activase, ATP synthase, oxygen-evolving enhancer proteins and many heat shock proteins (HSPs). In particular, small heat shock proteins (sHSPs), HSP70 and Cpn60 increase in abundance with heat. Many of these most responsive proteins to heat interact with one another and understanding the nature of this interaction remains a priority of future research. Including more staggered application of heat over longer periods to account for acclimation processes and expanding studies to include more reproductive tissues will improve our ability to heat-proof crops in a warmer world.