"Discoveries of DNA sequence that contain different languages, each one with multiple purposes, are utterly defying evolutionary predictions. What was once hailed as redundant code is proving to be key in protein production.
Proteins are made of strings of amino acids encoded in the protein-coding regions of genes. A previous discovery demonstrated the same three-sequence series of letters in the DNA that code for an amino acid (called a codon), can also tell specialized proteins that turn on genes (called transcription factors) where to bind to the DNA in the genome.2 However, a new discovery is
Codons appear to possess a redundancy. The first two bases in the codon structure are the same, but the third base can vary. For example, the codons GGU, GGC, GGA, and GGG all encode the same amino acid called glycine. When scientists first discovered this phenomenon, they called the variation in the third base a “wobble” and, out of ignorance, simply relegated the variability as redundant. In other words, they assumed that all the different codon variants for a given amino acid were functionally equivalent.
As an mRNA transcript copy of a gene is used to make a protein at cellular machinery sites called ribosomes, periodic pauses occur as the protein is produced and funneled out of a tunnel-like structure. The specific sequence and rate of pausing is critical to the folding of the protein into its proper three-dimensional shape which occurs during the building process in the ribosome. Many different types of cellular machines aid in this folding process, including the ribosome tunnel itself. Because the translation (the making of a protein from an RNA transcript) and the folding of the protein are linked together, the processes are called co-translational.
Researchers in this new study show that the variability in the third base of codons is not redundant at all, but a specific type of cellular language interpreted by the ribosome telling it when to pause and how to regulate the rate at which the protein is made. This ultimately has an effect on the folding of the protein into its proper three-dimensional shape.
Not only does a codon provide the information for which specific amino acid to add in the making of protein, but the variant of that codon influences the information needed on how to regulate its folding. Thus, you have two different sets of information encoded in different languages in the same section of DNA!" ICR
I will praise You
because I have been remarkably and wonderfully made.
Your works are wonderful,
Psalm 119:14 HCSB
