Explain the process of translation. As a component of your explaination, but not your whole explanation, include the function of the three major types of RNA in the translation process.
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1. Activation of Amino acids : This reaction is brought about by binding of an amino acid with ATP. The step requires enzyme called amino acyl RNA synthetases.
2. Transfer of amino acid to tRNA : The amino acid is transfered to tRNA. As a result enzyme and ATP are liberated.
3. Initiation of Polypeptide chain :Charged tRNA shifts to ribosome. Ribosome consists of structural RNAs and so different proteins. The information for sequence of amino acid is present in sequence of bases of mRNA. Inititiation of polypeptide chain in prokaryotes is always brought about by amino acid methionine which is regularly coded by codon AUG.
[ NOTE : mRNA has some additional sequences tat are not translated and are referred as untranslated regions ( UTR ). The UTRs are present at both 5' and 3' ends. They are required for efficient translation process. ]
4. Elongation : During this, complexes composed of amino acid, linked to tRNA subsequently bind to appropriate codon in mRNA forming the complementary bases with tRNA anticodon. Ribosomes moves aling mRNA towards it 3'end . This shift of ribosome along mRNA is called translocation. Hydrolysis of GTP provides energy. This shift releases of tRNA which is empty.
5. Termination : The termination of polypeptide is signalled by one of the 3 terminal triplets in mRNA. There are UAG, UAA and UGA. At the time of termination , terminal codon immediately follows in last amino acid codon. After this, polypeptide chain, tRNA and mRNA are released. The subunits of ribosomes get dissociated.
2. Transfer of amino acid to tRNA : The amino acid is transfered to tRNA. As a result enzyme and ATP are liberated.
3. Initiation of Polypeptide chain :Charged tRNA shifts to ribosome. Ribosome consists of structural RNAs and so different proteins. The information for sequence of amino acid is present in sequence of bases of mRNA. Inititiation of polypeptide chain in prokaryotes is always brought about by amino acid methionine which is regularly coded by codon AUG.
[ NOTE : mRNA has some additional sequences tat are not translated and are referred as untranslated regions ( UTR ). The UTRs are present at both 5' and 3' ends. They are required for efficient translation process. ]
4. Elongation : During this, complexes composed of amino acid, linked to tRNA subsequently bind to appropriate codon in mRNA forming the complementary bases with tRNA anticodon. Ribosomes moves aling mRNA towards it 3'end . This shift of ribosome along mRNA is called translocation. Hydrolysis of GTP provides energy. This shift releases of tRNA which is empty.
5. Termination : The termination of polypeptide is signalled by one of the 3 terminal triplets in mRNA. There are UAG, UAA and UGA. At the time of termination , terminal codon immediately follows in last amino acid codon. After this, polypeptide chain, tRNA and mRNA are released. The subunits of ribosomes get dissociated.