GENE2230 Lecture Notes - Lecture 4: Start Codon, Reading Frame, Ef-Tu
Document Summary
This means that nucleotides are read consecutively in sets of 3, with each set specifying a codon. Reading frame refers to how the genetic sequence is being read. For every codon, there are 3 ways in which the codon can be read. To set the correct reading frame, we need the initiation codon: aug in mrna, atg in dna. Hence, the codons are then read in successive groups of 3 after the initiation codon is established. Degeneracy of the genetic code and the wobble base pairing. One amino acid is encoded by 3 consecutive nucleotides and each nucleotide can have 1 out of 4 of the bases. If we use the number of cases, we can get 64 possible amino acids, which means we have 61 sense codons and 3 stop codons. However, we only have 20 amino acids, which means that the code is degenerate. Codons that specify the same amino acids are considered synonymous.
