In a new study published in the journal Science, researchers at the University of Utah discovered that the building blocks of a protein, known as amino acids, can be assembled without blueprints from DNA and messenger RNA (mRNA).
In the study, the researchers discovered a new protein, Rqc2, which plays a role much like that of mRNA, and specifies which amino acids should be added in a cellular mechanism. Adam Frost, assistant professor at University of California, says, "In this case, we have a protein playing a role normally filled by mRNA."
Researchers fine-tuned a technique known as "cryo-electron microscopy" in order to flash freeze the cells, followed by visualizing the quality control machinery in the active cells.
To describe the process, researchers compared the cell to a well-run factory. The ribosomes are like the machines on a protein assembly line that links amino acids together in a specific order determined by the genetic code. If something goes wrong, the ribosome is disassembled and they partly made protein is recycled.
According to this new study, before recycling is complete, the protein Rqc2 can prompt the ribosome for the addition of two of the twenty total amino acids such as alanine and threonine, in any order.
Researchers believe this seemingly illogical sequence is likely to serve specific purposes. The code signals could get destroyed, or it could be part of a test to see whether the ribosome is working properly.
Peter Shen, the study's first author currently doing a postdoctoral fellowship in Biochemistry at the University of Utah, called the findings "surprising" and says that "the discovery reflects how incomplete our understanding of biology is."
These findings could play a large role in the development of new therapies designed to treat neurodegenerative diseases such as Alzheimer's, Amyotrophic lateral sclerosis (ALS) and Huntington's.
"Nature is capable of doing a lot more than what has been earlier thought," Shen said.
More than five million Americans are living will Alzheimer's disease and it kills more than 500,000 each year. The disease is the most costly in the nation with a total spent estimated at $214 billion last year, including $150 billion in costs to Medicare and Medicaid.
With the implication that this new research could lead to new therapies for patients suffering from Alzheimer's and other neurodegenerative diseases, scientists hope to use this data as a first step towards improving treatment and quality of life for all people suffering from neurological diseases.
