Har Gobind Khorana and his colleagues performed numerous experiments translating synthetic mRNAs. In one experiment, an mRNA molecule with a repeating UG dinucleotide sequence was assembled and translated.

If the genetic code were a doublet code instead of a triplet code, how would the result of this experiment be different?

Verified step by step guidance

1. <span>Understand the concept of the genetic code: The genetic code is a set of rules by which information encoded in mRNA sequences is translated into proteins by living cells. In the standard genetic code, a triplet of nucleotides (codon) specifies a single amino acid.</span>
2. <span>Consider the implications of a doublet code: If the genetic code were a doublet code, each codon would consist of two nucleotides instead of three. This would significantly alter the way mRNA sequences are translated into proteins.</span>
3. <span>Analyze the repeating UG dinucleotide sequence: In the given experiment, the mRNA sequence is a repeating UG pattern. In a triplet code, this sequence would be read as UGU GUG UGU GUG, etc., potentially coding for a specific sequence of amino acids.</span>
4. <span>Predict the translation outcome with a doublet code: With a doublet code, the repeating UG sequence would be read as UG UG UG UG, etc. This would result in a different set of codons and, consequently, a different sequence of amino acids.</span>
5. <span>Consider the diversity of possible proteins: A doublet code would have only 16 possible codons (4^2), compared to 64 possible codons (4^3) in a triplet code. This would limit the diversity of proteins that could be synthesized, as fewer amino acids could be specified.</span>

Key Concepts

Genetic Code

The genetic code is the set of rules by which information encoded in genetic material is translated into proteins. It consists of codons, which are sequences of three nucleotides that correspond to specific amino acids. Understanding the genetic code is crucial for interpreting how sequences of nucleotides dictate the synthesis of proteins.

Triplet Code vs. Doublet Code

The triplet code refers to the use of three nucleotides (codons) to specify each amino acid in protein synthesis, allowing for 64 possible combinations. In contrast, a doublet code would use pairs of nucleotides, resulting in only 16 combinations. This difference significantly impacts the complexity and diversity of proteins that can be synthesized.

Translation Process

Translation is the process by which ribosomes synthesize proteins using mRNA as a template. During translation, the ribosome reads the mRNA codons and assembles the corresponding amino acids into a polypeptide chain. The efficiency and accuracy of this process depend on the structure of the genetic code, which determines how sequences are interpreted.