The newest Nobel Prize in Physiology or Medicine has been
awarded to Yoshinori Ohsumi for his work on understanding and elucidating the mechanisms
of autophagy. He has a doctorate of science from the University of Tokyo and
has had professorships at multiple colleges in Japan. Much of his work has been
on the vacuole of simple yeast. His decades of research have led to wide
ranging advances in the understanding of autophagy and its relation to bodily
processes. He also characterized many of the genes that code for the proteins
involved in autophagy, as well as some mutations of the same genes.
Autophagy is the mechanism by which cells degrade and reuse
cellular components that are no longer necessary. It involves the
sequestration, transport, degradation, and recycling of material. The body recycles components through the use
of lysosomes, one part of the autophagy process. Autophagy is an important part
of many biochemical processes and has been linked to many different causes and
outcomes in cells from a variety of species. There are three types of
autophagy: macroautophagy, microautophagy, and chaperone-mediated autophagy.
Autophagy is commonly triggered in response to physical stresses on the body,
that forces it to efficiently clean and reuse cell materials. Some of these
physical stresses include starvation and disease.
The degradation caused by autophagy helps power the cell in
these trying times and it can also protect against infection and viruses. It
has a role in a multitude of disease responses and can cause programmed cell
death. Having said that there are many diseases that occur because of
malfunctions in the autophagy process. When the mechanism malfunctions because
of mutations in the genes that code for proteins involved in the process there
has been linked to osteoarthritis, cancer, and Parkinson disease.
I highly recommend reading the interview of Yoshinori Ohsumi
that I linked below. He talks about how he followed his interests to continue
his research and at the end he shares some advice to younger scientists.
For more reading:
An interesting interview of Professor Ohsumi where he talks
about the progression of his work:
Yoshinori Ohsumi:
Autophagy from beginning to end
By: Caitlin
Sedwick
J Cell Biol. 2012 Apr 16; 197(2): 164–165
Some more in depth information on autophagy:
Autophagy: process and function
By: Noboru Mizushima
http://genesdev.cshlp.org/content/21/22/2861.long
So is this essentially a way that the cells "jump ship"? From what I understand, they are getting rid of any unnecessary components when they experience a high-stress environment and focus that energy into keeping the cells alive. Hopefully my understanding is correct.
ReplyDeleteSo autophagy is another type of programmed cell death. But what is the purpose of "cleaning" after some type of stress? I would assume this requires energy to do and then reuse the componenets. What is this process trying to "clean" the cell from?
ReplyDeleteHw do the three types of autophagy differ?
ReplyDelete