Yoshinori Ohsumi of Japan was awarded a Nobel prize in medicine for his discovery of pathways of cells recycling their contents, a term called autophagy. Mutations in this process have been linked to a variety of diseases including cancer, Parkinson's disease, and type 2 diabetes . That is why the discovery of the pathway for this process as well as genes involved is so crucial.
Autophagy was proven to have the same mechanisms in yeast as in humans. It allows cells to rapidly provide energy when it's needed such as during starvation. It also eliminates pathogenic viruses and bacteria after their invasion, and eliminates damaged organelles and proteins. Mutations in autophagy genes as well as disruption of the process has terrible consequences.
Yoshinori Ohsumi's discoveries have allowed scientists all over the world to understand and do more experiments with autophagy processes, and use this understanding to hopefully cure many diseases in the future.