Differences Among Coding for Amino Acids

It has been stressed that DNA codes for amino acids. For any of the 64 codons, or combination of three bases, there is a specified amino acid. Previously, it was believed that this language was universal for all organisms, as show in laboratory generations.  However, the U.S. Department of Energy Joint Genome Institution found that for uncultivated microbes codons differ in the amino acid they inscribe. The study zoned in on the three stop codons, UAA, UGA and UAG where the chain then terminates.

It was found that in other organisms the stop codons actually code for an amino acid, thus the chain continues. The research led by Eddy Rubin concluded that each of these three codons have been reassigned in various ways. For instance, Bacteria and Eukaryotas each redefined a different stop codon. Archaea showed no change to these three codons. This data builds on unexplored areas within the tree of life.

I found this article interesting as it related to the evaluation of all life on a microscopic level. Research within DNA has only increased in popularity , thus the differences among organisms is foretelling to our past. How do our codes for amino acids differ and why? Are some of these stop codons not essential to life or only fundamental for certain organisms? This study opens up question and reasoning for evolution of life.

The article can be found here.

Your Stature Could Kill You!

Recent Studies done by Dr. Nilesh Samani and his colleagues at the University of Leicester explore the linkage between height and heart disease. For years doctors have recognized a trend that shorter people have a higher chance of developing heart disease, but the genetic explanation has remained a mystery.

This study focused on 180 genes known to be related to a person's height and found that the most probable cause of this is that these genes which regulate growth related to height also regulate growth and development of the arteries and vessels in the vascular system. When a person is shorter, their vascular system may also be smaller and underdeveloped, which increases the person's chances of developing coronary heart disease.

The study was published in The New England Journal of Medicine and stated that a person who is one standard deviation (6.5cm) shorter than another person will have a 13.5% higher chance of developing heart disease. Samani stated that, though it is not a sort-term possibility, he believes that studying the underlying genetic codes related to height and heart disease could lead to treatments in the future.

Who Proof Reads Our Amino Acids ?

In an article released by science daily researchers at the Cold Spring Harbor Laboratory and MIT have found out that there is a sort of role reversal in terms of what we would expect to be the proof reading structure. The building blocks of our amino acids are tRNA they work together with other cellular structures to make sure that all our amino acids are in proper order. So naturally we would think that our tRNA is the molecular structure that is also proof reading our amino acids, but it is just the opposite it is our RNA that is proof reading our amino acids. When an amino acid is done forming the tRNA puts a code CCA at the end, but if it is mutated it will put two CCA codings. This then makes sure that that amino acid structure is not put anywhere. The team then wanted to find out how does the CCA adding enzyme distinguish between a mutated and normal tRNA. They used X-Ray crystalography to find out that the enzyme it self cannot tell the difference between the two, it is the RNA that goes back and proof reads itself.

This article was very interesting because it tackles an issue that not many of us think about. We know how the amino acid sequence works, but we do not always consider what would happen if something were to go wrong in our working theory. In a study like this it was especially important because if the researchers did not do this we may have just assumed tRNA took care of it because it took care of everything else. As we move further in our research it is always very interesting to see how different advancements will affect our future. This could be the next step in ending genetic mutations.

Primary Article
Secondary Article