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Nature Reviews. Microbiology May 2015Ribosomes that stall during translation need to be rescued to ensure that the protein synthesis capacity of the cell is maintained. Stalling arises when ribosomes become... (Review)
Review
Ribosomes that stall during translation need to be rescued to ensure that the protein synthesis capacity of the cell is maintained. Stalling arises when ribosomes become trapped at the 3' end of an mRNA, which occurs when a codon is unavailable, as this leads to the arrest of elongation or termination. In addition, various factors can induce ribosome stalling in the middle of an mRNA, including the presence of specific amino acid sequence motifs in the nascent polypeptide. Almost all bacteria use a mechanism known as trans-translation to rescue stalled ribosomes, and some species also have other rescue mechanisms that are mediated either by the alternative ribosome-rescue factor A (ArfA) or ArfB. In this Review, I summarize the recent studies that have demonstrated the conditions that trigger ribosome stalling, the pathways that bacteria use to rescue stalled ribosomes and the physiological effects of these processes.
Topics: Bacteria; Gene Expression Regulation, Bacterial; Protein Biosynthesis; Ribosomes
PubMed: 25874843
DOI: 10.1038/nrmicro3438 -
Cell Cycle (Georgetown, Tex.) 2015
Topics: Adaptor Proteins, Signal Transducing; CDC2 Protein Kinase; Cell Cycle; Cell Cycle Proteins; Cyclin-Dependent Kinases; Humans; Mitosis; Phosphoproteins; Phosphorylation; Protein Biosynthesis
PubMed: 26496165
DOI: 10.1080/15384101.2015.1084192 -
Methods (San Diego, Calif.) Mar 2018
Topics: Gene Expression Regulation; Molecular Biology; Protein Biosynthesis
PubMed: 29571431
DOI: 10.1016/j.ymeth.2018.03.005 -
Science (New York, N.Y.) Jun 2016
Topics: Animals; Gene Expression Regulation; Humans; Protein Biosynthesis; RNA
PubMed: 27313036
DOI: 10.1126/science.352.6292.1406 -
Trends in Neurosciences Jan 2005Prevailing models of memory identify mRNA translation as necessary for long-lasting information storage. However, there are enough instances of memory storage in the... (Review)
Review
Prevailing models of memory identify mRNA translation as necessary for long-lasting information storage. However, there are enough instances of memory storage in the virtual absence of protein synthesis to prompt consideration of alternative models. A comprehensive review of the protein synthesis literature leads us to conclude that the translational mechanism is exclusively a permissive, replenishment step. Therefore, we propose that post-translational modification (PTM) of proteins already at the synapse is the crucial instructive mechanism underlying long-lasting memory. A novel feature of this model is that non-random spontaneous (or endogenous) brain activity operates as a regulated positive-feedback rehearsal mechanism, updating network configurations by fine-tuning the PTM state of previously modified proteins. Synapses participating in memory storage are therefore supple, a feature required for networks to alter complexity and update continuously. In analogy with codons for amino acids, a long-lasting memory is represented by a 'degenerate code' - a set of pseudo-redundant networks that can ensure its longevity.
Topics: Animals; Humans; Memory; Models, Neurological; Nerve Tissue Proteins; Protein Biosynthesis; Protein Processing, Post-Translational; Synaptic Transmission
PubMed: 15626492
DOI: 10.1016/j.tins.2004.11.006 -
Trends in Plant Science Aug 2014Light-regulated gene expression, mediated by photoreceptors, acts as a multifaceted regulator to control the abundance of functional genes at different levels. Two... (Review)
Review
Light-regulated gene expression, mediated by photoreceptors, acts as a multifaceted regulator to control the abundance of functional genes at different levels. Two recent genome-wide studies by Wu et al. and Liu et al. show that light controls gene expression at post-transcriptional and translational level through alternative splicing and translational regulation, respectively.
Topics: Gene Expression Regulation, Plant; Light; Photoreceptors, Plant; Plants; Protein Biosynthesis; RNA Splicing
PubMed: 24928178
DOI: 10.1016/j.tplants.2014.05.004 -
Getting the message in protein synthesis. Keystone Symposium on Translational Regulatory Mechanisms.EMBO Reports Oct 2008
Review
Topics: Animals; Gene Expression Regulation; Humans; Protein Biosynthesis; Ribosomes
PubMed: 18758437
DOI: 10.1038/embor.2008.165 -
Biochemical Society Transactions Apr 2011mTOR (mammalian target of rapamycin) forms two distinct types of complex, mTORC (mTOR complex) 1 and 2. Rapamycin inhibits some of the functions of mTORC1, whereas newly... (Review)
Review
mTOR (mammalian target of rapamycin) forms two distinct types of complex, mTORC (mTOR complex) 1 and 2. Rapamycin inhibits some of the functions of mTORC1, whereas newly developed mTOR kinase inhibitors interfere with the actions of both types of complex. We have explored the effects of rapamycin and mTOR kinase inhibitors on general protein synthesis and, using a new stable isotope-labelling method, the synthesis of specific proteins. In HeLa cells, rapamycin only had a modest effect on total protein synthesis, whereas mTOR kinase inhibitors decreased protein synthesis by approx. 30%. This does not seem to be due to the ability of mTOR kinase inhibitors to block the binding of eIFs (eukaryotic initiation factors) eIF4G and eIF4E. Analysis of the effects of the inhibitors on the synthesis of specific proteins showed a spectrum of behaviours. As expected, synthesis of proteins encoded by mRNAs that contain a 5'-TOP (5'-terminal oligopyrimidine tract) was impaired by rapamycin, but more strongly by mTOR kinase inhibition. Several proteins not known to be encoded by 5'-TOP mRNAs also showed similar behaviour. Synthesis of proteins encoded by 'non-TOP' mRNAs was less inhibited by mTOR kinase inhibitors and especially by rapamycin. The implications of our findings are discussed.
Topics: Animals; Humans; Isotope Labeling; Models, Biological; Protein Biosynthesis; Protein Kinase Inhibitors; Sirolimus; TOR Serine-Threonine Kinases
PubMed: 21428917
DOI: 10.1042/BST0390446 -
Trends in Biochemical Sciences Apr 2006Polypeptides chains are segregated by the translocon channel into secreted or membrane-inserted proteins. Recent reports claim that an in vivo system has been used to... (Review)
Review
Polypeptides chains are segregated by the translocon channel into secreted or membrane-inserted proteins. Recent reports claim that an in vivo system has been used to break the "amino acid code" used by translocons to make the determination of protein type (i.e. secreted or membrane-inserted). However, the experimental setup used in these studies could have confused the derivation of this code, in particular for polar amino acids. These residues are likely to undergo stabilizing interactions with other protein components in the experiment, shielding them from direct contact with the inhospitable membrane. Hence, it is our view that the "code" for protein translocation has not yet been deciphered and that further experiments are required for teasing apart the various energetic factors contributing to protein translocation.
Topics: Animals; Genetic Code; Humans; Membrane Proteins; Protein Biosynthesis; Protein Processing, Post-Translational; Protein Transport; Signal Recognition Particle
PubMed: 16530414
DOI: 10.1016/j.tibs.2006.02.002 -
Biochemistry Oct 1988
Review
Topics: Animals; Humans; Models, Genetic; Protein Biosynthesis; Protein Processing, Post-Translational; Proteins
PubMed: 3069123
DOI: 10.1021/bi00421a001