Deciphering Mechanics of Chaperonin

Deciphering Mechanics of Chaperonin

Chaperonin II is the eukaryotic protein (Chaperonin I is for prokaryotes), whose primary purpose is to aid and promote the correct folding of newly translated proteins and proteins that

have been denatured, also acting as a barrier to "protect" the protein from non-ideal environmental situations.

Recently, a largely collaborative research project between DOE/Lawrence Berkeley National Laboratory, MIT, and Stanford successfully identified a new region that they termed "the nucleotide-sensing loop" that acts as a detector on the chaperonin for the presence of ATP, which activates the chaperonin protein to perform its duties. This region is a critical control element in the functions of the chaperonin, and was previously unrecognized.

The researchers utilized the laboratory's Advanced Light Source (ALS), using x-ray crystallography to visualize and determine the structure of the nucleotide-sensing loop of the chaperonin. In this study, the team performed these experiments on archaeon chaperonin, however, they are now working to perform similar feats TRiC, human chaperonin.

Chaperonin II consists of 3 domains, that when the "lid" of the chaperonin opens to accommodate the protein to be folded, the 3 domains all shift in conformation. Evidence from this study indicates that the nucleotide-sensing loop (itself just a subunit) acts as the communicator, dictating for the 3 domains to move.

This article is particularly relevant because of the absolute necessity of chaperonin in all aspects of the body, making knowledge about this protein even more essential. Misfolding of proteins directly correlates with pathological results, and studying whether chaperonin is fully responsible for these misfoldings and if so, why this occurs is very important. Many diseases such as Alzheimer's, Parkinson's, and certain cancers have been attributed to these misfolding proteins. Further research in this field can also help for the manipulation of these chaperonin molecules which can be an essential tool in protein engineering. The relevance to this class mostly involves the fact that we have studied this protein and some of the diseases associated with its malfunction, including those listed above. Learning and understanding more about the mechanisms behind the body's working seems the primary goal of physiology, making this even more relevant.

http://www.sciencedaily.com/releases/2012/02/120224140514.htm