Protein Degradation

A Biocompare article titled Penn Researchers Link Cell’s Protein Recycling Systems indicates problems that can come about when normal cellular protein disposal systems become defective. Cited is related data gathered by researchers from the University of Pennsylvannia School of Medicine and published in the journal Nature.

The article highlights the interesting fact that there are two cellular pathways which break down proteins. Proper protein disposal is essential to the well being of cells. Ubiquitin, a small but versatile protein, tags proteins to be degraded in what is called the ubiquitin-proteasome pathway. Breakdown occurs in a structure called the proteasome. A second pathway involves the autophagy-lysosomal system.

An interesting finding is that the systems can compensate for each other. Proteins can actually be shifted from one system to the other. An accumulation of proteins can be toxic to cells.