In order for your cells to properly synthesize proteins, they require a blueprint showing how to assemble them, which must come from your genetic material. Or at least, that's what scientists have long believed. But the recent discovery of a protein that is capable of assembling other proteins without the need for a genetic blueprint could change our fundamental understanding of these biological processes forever, reports Sci-News.
"This surprising discovery reflects how incomplete our understanding of biology is. Nature is capable of more than we realize," said Dr. Peter Shen of the University of Utah, the first author of the paper, which was published in the journal Science.
Proteins are the building blocks of life, each created from a chain of amino acids. Your cells synthesize proteins thanks to cellular structures called ribosomes, which operate like factories, taking amino acids and assembling them in a pattern according to your genetic blueprint. Without the instructions offered by the genetic component, the ribosomes can't assemble proteins properly. Some scientists believe that failures in this process could lead to neurodegenerative diseases such as Alzheimer’s, amyotrophic lateral sclerosis (ALS) or Huntington’s.
The new study, which comes from a team of researchers from the University of Utah, University of California and Stanford, has revealed another key component of protein synthesis, one which could lead to new ways of treating these diseases. Researchers discovered a protein named Rqc2 which is also capable of instructing ribosomes, even in the absence of genetic input.
Rqc2 was found to spring into action when the normal protein-building process fails, prompting the ribosome to begin adding two particular amino acids — alanine and threonine — over and over, and in any order.
The resultant truncated proteins, with their random sequence of alanines and threonines, end up looking very strange and probably don't function properly, but this is the first evidence of non-genetic material offering instructions for protein synthesis.
Scientists suspect the odd proteins created by Rqc2 serve some purpose — perhaps as part of some kind of cellular "test" to see if the ribosomes are functioning properly — but more research in necessary to know for sure.
“There are many interesting implications of this work and none of them would have been possible if we didn’t follow our curiosity. The primary driver of discovery has been exploring what you see, and that’s what we did. There will never be a substitute for that,” said Dr. Onn Brandman, another of the study's authors.
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