THE HUMAN PROTEIN ATLAS BLOG
Image of the week - Autophagy and the nobel prize
This week the 2016 Nobel Prize in Physiology or Medicine was announced and has been awarded to Yoshinori Ohsumi for his work in with understanding autophagy. Congratulations to Dr. Ohsumi on his well deserved award! Please read the link above for a great and brief explanation of Dr. Ohsumi's contributions and other important discoveries related to autophagy.
This week we highlight DNA damage regulated autophagy modulator 2 (DRAM2), a well known inhibitor of autophagy. Figure 1 shows an example of DRAM2 in U2 OS human osteosarcoma cells.
So what exactly is autophagy, and why does it deserve the Nobel Prize?
Autophagy, which literally means "self-eating", is the process through which your cell digests things inside it. This process occurs by the encapsulation of cytoplasmic materials in vesicles which are then transported to and fused with lysosomes. As seen in a previous image of the week, lysosomes are acidic vesicles that break down material inside your cells.
Autophagy can even swallow whole organelles such as mitochondria. Although it's a little scary to think that you are eating yourself alive, this process is perfectly natural and in fact is essential for maintaining healthy cells. Autophagy allows cells to reclaim nutrients and energy from various parts of the cell and occurs naturally when proteins or organelles are damaged or dysfunctional (Kaur J & Debnath J 2015). Autophagy can also be induced by various cellular stimuli, including cellular starvation during which time the cell attempts to reclaim and save as much energy from existing sources as possible ( Das G et al. 2012).
Autophagy also plays a key role in detection and repair of DNA damage in the cell and sources of DNA damage such as radiation have been shown to trigger autophagy (Rodriguez-Rocha H et al. 2011). When not properly repaired, DNA damage can lead to mutagenesis and cancer.
The dysfunction of autophagy has also been linked to several major diseases. Specifically, the ATG family of genes have been shown to contain mutations in neurodegenerative diseases, infectious diseases, and cancers (Jiang P and Mizushima N 2014). Beyond disease, the inhibition of autophagy pathways has also been shown to lead to symtoms that resemble aging in mammals leading researchers question what link the two processes might have (Rubinsztein D C et al. 2011).
We'd like to again congratulate Dr. Ohsumi on receiving the prize, but more importantly thank him for his contribution to our understanding of one of the key mechanisms of the human cell.