Translation in an important, and complex feature of the process of protein synthesis. Genetic information codes for proteins via protein syntheis, this is an essential process as proteins are responsible for the vast majority of cell function and structure. Protein synthesis involves mRNA and tRNA along with other proteins and has three main steps:
- DNA replication
Translation is the most complex, it consists of the nucleotide sequence of mRNA being translated into the amino acid secquence of the specific protein. The direction that translation is carried out is very significant; it occurs in the same direction as transcription ( 5'-3') this results in proteins being produced more efficiently as translation can occur during transcription .
The mRNA and tRNA play very important specific roles during translation; firstly mRNA acts as a template for the production of the polypeptide chain from the genetic code. The genetic code had three important features:
- Triplet code
The genetic code is degenerate because it has 64 codons but only 20 amino acids, therefore most amino acids are coded for by more than one codon. 61 of these codons are used for amino acids and 3 are used as stop codons which will end translation. Only 1 codon is used for the amino acid Methionine and this is the start codon (AUG).
The tRNA acts as an adaptor molecule to decode the mRNA into the protein, it interacts with the mRNA through its anticodon.The tRNA is also responsible for proof-reading the amino acid chain, this ensures that mistakes are very rare (less than 1 per 10000). This is done by many tRNA having an editing site as well as an activation site. These change or reject amino acids if they are larger or smaller than they should be.
- ↑ Berg et al., 2007:869