How is RNA read?

RNA is read from 5' to 3' during processes such as transcription and translation. This directionality is crucial because it dictates how nucleotides are added to the growing RNA strand. In transcription, RNA polymerase synthesizes RNA by adding ribonucleotides, which align with the DNA template strand in the 5' to 3' direction. Similarly, during translation, ribosomes read the mRNA codons from the 5' end to the 3' end, facilitating the proper incorporation of amino acids into the growing polypeptide chain.

The 5' to 3' reading direction is essential for accurate gene expression, as it ensures that the encoded information in the nucleotide sequence is interpreted correctly. This orientation allows the ribosomes to correctly match tRNAs with their corresponding codons on the mRNA, ultimately producing functional proteins.