Biochemistry 2280A Lecture Notes - Lecture 13: Start Codon, Transfer Rna, Reading Frame

• School: Western University
• Department: Biochemistry
• Course: Biochemistry 2280A
• Professor: Derek Mc Lachlin

Document Summary

Translation: the decoding of mrna by the ribosome to produce a protein from the n-terminus to the c-terminus. This is a complex process requiring many rna and protein factors. Genetic code: the mrna spells out the amino acid code in 3 letter words called codons. Translation initiation: translation begins at the aug (start) codon with a special initiator trna that carries methionine initiator trna is positioned at the p-site. In eukaryotes, initiator trna is loaded onto the small subunit with initiation factor proteins: loaded small subunit recognizes 5" cap of the mrna and moves 5" 3" until it finds the. Initiation factor proteins then dissociate, allowing the large subunit to bind the small subunit. Termination: when a stop codon reaches the a-site of the ribosome, release factor proteins associate with the ribosome and cause the peptidyl transferase activity to catalyze the addition of a water molecule to the end of the chain.