Autophagy was first proposed in the 1960s after it was found that a cell can recycle its own contents by packing up organelles to be recycled into vesicles and transported to a lysosome containing digestive ezymes where they degrade. This provides fuel for energy and building blocks for the renewal of cell components.
Ohsumi’s work started in the 1990s primarily using baker’s yeast to find discoveries relating to autophagy in response to starvation and infection. He began his work by studying how proteins degraded in the vacuole, by removing the vacuolar degradation enzymes from yeast the cells essentially ‘starved’. This in turn caused autophagy to begin, it is possible to see this under a microscope as the autophagosomes (responsible for degradation) will accumulate and be visible under a microscope. If there were vacuolar degradation enzymes these vesicles would have degraded and would never have been visible. Then by hundreds of experiments with different strains of yeast he was able to identify the key genes, common throughout all mutant strains that were necessary for starting autophagy.
Despite Ohsumi’s work being on yeast cells the mechanism for autophagy in humans is much the same This is beneficial as autophagy has been linked to Parkinson’s, type 2 diabetes and cancer. By understanding more about the process of autophagy we can learn more about how these diseases develop. As a direct result of this discovery ‘intense research is now ongoing to develop drugs that can target autophagy in various diseases’