Ribosomes involved in protein synthesis could lie free in the cytoplasm or are bound to membranes of endoplasmic reticulum. Free ribosomes synthesise protein without a signal sequence, and continue synthesis until the polypeptide is completed. Such a protein may assume its three-dimensional conformation with the help of chaperones present in the cytosol. Some of the important destinations for proteins synthesised [...]
The following points highlight the eight important steps in maturation of proteins. The steps are: 1. Protein folding and Chaperones 2. Enzymes in Protein Folding 3. Protein Cleavage 4. Glycosylation 5. Modification by Lipids 6. Protein Degradation 7. The Ubiquitin-Proteasome Pathway 8. Lysosome Mediated Proteolysis. Step # 1. Protein Folding and Chaperones: The experiments of Anfinsen and collaborators half a [...]
The processed RNA molecules take part in protein synthesis with the help of ribosomes. All the three types of RNAs are involved in protein synthesis in the following main steps: (i) Activation of amino acids, (ii) Transfer of amino acid to tRNA, (iii) Initiation of protein synthesis, (iv) Elongation of the polypeptide chain. During the process of translation the genetic [...]