In an experiment to decipher the genetic code, a poly-AC mRNA (ACACACAC...) is synthesized. What pattern of amino acids would appear if this sequence were to be translated by a mechanism that reads the genetic code as
A triplet with overlaps?

Verified step by step guidance

1. Understand the structure of the poly-AC mRNA sequence: The sequence alternates between adenine (A) and cytosine (C), forming a repeating pattern of ACACACAC... This sequence will be read in triplets during translation.
2. Determine the possible overlapping triplets: Since the sequence is read with overlaps, the first triplet is ACA, the second triplet is CAC, the third triplet is ACA again, and so on. This overlapping mechanism ensures that each nucleotide is part of multiple codons.
3. Consult the genetic code table: Use the standard genetic code table to identify the amino acids corresponding to each triplet. For example, ACA codes for threonine (Thr), and CAC codes for histidine (His).
4. Predict the pattern of amino acids: Based on the alternating triplets ACA and CAC, the resulting amino acid sequence will alternate between threonine (Thr) and histidine (His).
5. Summarize the repeating pattern: The translation of the poly-AC mRNA sequence with overlapping triplets will produce a repeating pattern of amino acids: Thr-His-Thr-His...

Key Concepts

Genetic Code

The genetic code is a set of rules that defines how sequences of nucleotides in mRNA are translated into amino acids. It consists of codons, which are groups of three nucleotides that correspond to specific amino acids or stop signals during protein synthesis. Understanding the genetic code is essential for predicting the amino acid sequence from an mRNA strand.

Overlapping Codons

In a translation mechanism that reads overlapping codons, the reading frame shifts after each amino acid is added, allowing for the same nucleotide sequence to code for multiple amino acids. This means that the first codon overlaps with the second, and so on, creating a different pattern of amino acids than in non-overlapping translation. This concept is crucial for analyzing how the poly-AC mRNA would be translated.

Translation Process

Translation is the process by which ribosomes synthesize proteins using mRNA as a template. During translation, the ribosome reads the mRNA sequence in codons and assembles the corresponding amino acids into a polypeptide chain. Understanding the mechanics of translation, including the role of tRNA and ribosomes, is vital for determining the resulting amino acid sequence from the given mRNA.