Mutation reduces energy waste in plants

In Germany, researchers at the Ruhr-Universität Bochum identified several thousand proteins, determined their respective amounts in mutant and reference lines and combined the results obtained with measurements of photosynthetic performance. They found that the combination of two mutations could help convert carbon dioxide into biomass by plants more efficiently.

One of the mutations is characterized by the fact that the import of proteins into the chloroplast is disturbed. Chloroplasts are dependent on importing a large part of their proteins from the cytoplasm. “A defect in the import cannot produce enough chlorophyll – the plants are not green, it is an albino mutant,” says first author Julia Grimmer. The other mutation affects the function of the so-called proteasome. This protein complex is responsible for breaking down proteins in the cytoplasm. The functionality of the proteasome is changed in the mutant.

“The combination of these two mutations has resulted in a new plant phenotype,” explains Sacha Baginsky. “The plants are greener than the albino mutant and also do more photosynthesis. This surprised us because it contradicts intuition. If you add a second defect to the first one, the function improves. ”

Studies with wild-type Arabidopsis plants showed that the improvement in photosynthesis performance by the proteasome mutation also occurs independently of the import mutation. This could have the potential to make the conversion of carbon dioxide into biomass by plants more efficient.