Researchers at the Proteome Center Tuebingen discover a new form of the protein ubiquitin that is involved with inflammation and cell death.

I thought it would be appropriate to discuss this article because it brings up several points that we should be moderately familiar with: ubiquitin, and methods for determining intracellular levels of various compounds. We are aware of what ubiquitin is: a protein that binds to other proteins and is involved with regulating the levels of those proteins. As ubiquitin binds to proteins it “marks” it for destruction and recycling. As more and more ubiquitin binds, it forms long chains in a process called polyubiquitylation. Previously there were only two forms of polyubiquitylation known. This new, third major form, is not found in the same amounts as the other two – it is typically found in amounts 30 times lower – and is classified by its linear form . Despite the relatively small amount of it discovered, it was found to play a major role in inflammation and cell death. It does so by modifying NEMO, an important regulatory protein in the NF-kappaB signal transduction pathway, is present. The NF-kappaB signal transduction pathway is one regulatory mechanism for inflammation processes and insight and research in this area can lead to new therapies for inflammation.

Discovery of this new form was difficult because of its relatively low concentration in comparison to the other two and the difficulty in distinguishing them apart from one another. Dr. Mirita Franz-Wachtel stated that, “Due to very small intracellular amounts of this modification we had to apply the most sensitive biochemical methods and instrumentation.” In fact, the most important method they had to use was mass spectrometry, a method that can measure the masses of ionized molecules. Using these methods scientists will hopefully be able to gain a deeper understanding of the protein complement of our cells and develop new and more efficient treatments.

http://www.sciencedaily.com/releases/2011/03/110331080039.htm