ABSTRACT
Protozoan ciliates are a group of unicellular eukaryotes. The special characteristics of stop codons usage in termination of protein biosynthesis in ciliates cells makes them an ideal model to study the mechanism of stop codon recognition of polypeptides release factors. To localize the functional positions of biomolecules in ciliates cell, we constructed a macronuclear artificial chromosome containing a gene encoding red fluorescence protein (EoMAC_R) based on the structural characteristics of ciliates chromosome. Three factors, L11, eRF1a, and eRF3 that are involved in termination process of protein synthesis were colocalized in Euplotes octocarinatus cells by using novel EoMAC_R and the previously constructed EoMAC_G. The results indicated that protein synthesis mainly occurred inside the "C" shape macronucleus, suggesting that EoMAC could be a useful tool for localizing biomolecules in ciliates cell.
Subject(s)
Chromosomes, Artificial , Codon, Terminator , Metabolism , Euplotes , Chemistry , Peptide Termination Factors , Genetics , Metabolism , Peptides , Metabolism , Protein Biosynthesis , Genetics , Protozoan Proteins , Genetics , Ribosomal Proteins , GeneticsABSTRACT
The process of protein synthesis is terminated by one of the three stop codons which are recognized by classⅠ polypeptide release factors.Subsequently, it could promote the hydrolysis of the ester bond of peptidy-tRNA, resulting in release of the nascent polypeptide.Recent results from cryoelectron microscopy, crystallography, NMR, molecular dynamic and biochemical experiments have shed considerable light on the function and structure of the classⅠ release factors.The progress in these aspects were summarized.