How cell processes round up and dump damaged proteins
A very large protease called a proteasome is responsible for degrading the vast majority of proteins in a cell; it may be made up of as many as 40 proteins.
UCH37 enzyme is one of the regulatory enzymes that associates with the proteasome.
What does ubiquitin protein do?
The cells in your body build up and break down proteins at a rapid rate. Ubiquitin attaches to proteins, tagging them for disposal. Tagged proteins are taken to proteasomes to be destroyed. Just before the protein enters the proteasome, ubiquitin is disconnected to be used again. src
Ubiquitin protein in addition to modifying other proteins, modifies itself resulting in a wide array of chains.. Some of these chains can have extensive branching. We found that UCH37 removes branch points from chains, allowing degradation to proceed.
Many cancer cells are essentially addicted to proteasome function, its cells produce proteins at such a fast rate that mistakes are made, and if these are not cleared out, cells can't function. Since UCH37 aids in clearing out proteins, it could be a useful therapeutic target to add to the proteasome inhibitors that have already been successful in the clinic.
We had to come up with a way to generate a wide variety of ubiquitin chains that would represent the potential diversity in a cell. Using that new library of ubiquitin chains allowed us to interrogate the activity of UCH37 in a controlled setting. That series of experiments gave us the first clue that this enzyme was doing something unique.
study by Eric Strieter.
src - https://www.umass.edu/newsoffice/article/how-cell-processes-round-and-dump-damaged
ref - https://www.eurekalert.org/pub_releases/2020-11/uoma-hcp110620.php
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