In what direction is RNA read during the process of translation?

During the process of translation, RNA is read from the 5′ end to the 3′ end. This directional reading is crucial for synthesizing proteins accurately. The ribosome, which is the cellular machinery responsible for translation, scans the messenger RNA (mRNA) starting at the 5′ cap structure, which facilitates the binding of the mRNA to the ribosome. As the ribosome moves along the mRNA, it translates the nucleotide sequence into an amino acid sequence, linking them together in the specific order dictated by the codons on the mRNA. This ensures the correct polypeptide chain is formed, ultimately folding into a functional protein.

The 5′ to 3′ reading direction is essential because the genetic code is structured in codons, which are sets of three nucleotides. Each codon corresponds to a specific amino acid, and the ribosome must maintain the proper reading frame to avoid errors in the resulting protein synthesis.