Translation

Now that the DNA code has been read to make mRNA, the mRNA needs to be deciphered to make protein. This is the process of translation. Translation into protein is akin to translating a language. Both DNA and RNA use a different code, made of nucleotides. Yet protein is made of amino acids. In order for protein to be made from RNA, the language of nucleotides must be translated to the language of amino acids.

Translation is performed on a ribosome which is composed of rRNA and protein. During translation, tRNA deciphers the code on the mRNA and transfers the appropriate amino acid onto the growing polypeptide chain (protein). Three nucleotides, called a codon, translate to one amino acid. Translation begins when a start codon with the sequence AUG is found, this begins the reading frame of the mRNA. This continues until a stop codon is reached. Stop codons have the sequence of UAG, UAA, or UGA are termed as such because there is no tRNA complementary to these sequences, therefore translation ends when one of these sequences is encountered.