Deciphering The Protein Editing Code

By Dannielle Brown

Minor errors in protein production could be a thing of the past now with the aid of recent data collected by members of the Scripps Research Institute.
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Research conducted under the ever watchful eye of Professor Paul Schimmel of the Scripps Research Institute, could in the future hold the key to identifying underlying causes of certain diseases and possibly in time play a part in their demise.
This process of protein manufacturing is a somewhat complicated and vitally crucial process and one minute mistake can result in catastrophic effects. Many phases and components are involved in this method, such as the messenger RNA which acts as an instruction manual for protein synthesis, or the tRNA carrying amino acids. The majority of these tRNA only carry a singular amino acid at a time and are joined using an enzyme known as synthetase. These tRNA then unite together and form the specified protein.
Sometimes during protein synthesis the tRNA can accidentally combine with the incorrect amino acid. When this occurs and the problem is not rectified serious health consequences can result. After mind boggling amounts of investigating by scientists it is now understood that the segments of the synthetases that are responsible for the adhesion and recognition of tRNA and the correct amino acids are that precise that little to no editing is mandatory. But whatever little editing required was thought to have taken place at only one place.
But this new study tends to provide evidence that falsifies this claim. After studying Alanine (an amino acid found in everything from humans to birds) it was revealed that a second checkpoint was present. This other checkpoints function was to identify any mistranslations and the removal of any foreign amino acid (not Alanine) that attempted to bind with the Alanine tRNA.Surprisingly this second station of the enzyme synthetase also focuses on the same pair of nucleotides as the first station.
Many experiments were conducted on this second editing station. Including the separation of the enzyme from the rest, resulting in the observation that the enzyme still had the ability to removed incorrect amino acids from the Alanine TRNA.
The astonishing research that was conducted also lead to another discovery. That freestanding domains (genome-encoded fragments that have not yet been proven to have a particular function) have a very similar genetic sequence to the second editing location found in the Alanine enzyme synthetase. These freestanding domains were also experimented upon and were shown to independently eliminate the incorrect amino acids.
This result provokes the thought that these fragments could act as a third checkpoint, used to once again observe whether the protein synthesis was a success.
Further research is now being conducted with the assistance of other scholars from many prestigious institutions to see if this new knowledge can be put into use in the medical world, either by complete irradiation of some diseases caused by mutations or just assist in the comprehension of conditions that are not yet understood.

Reference - http://www.sciencedaily.com/releases/2008/01/080103090655.htm