Mystery at the heart of life

_{News
December 21, 2014

Cell biology, Intelligent Design, News

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Cell biology
Intelligent Design
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By Biologic Institute’s Ann Gauger, at Christianity Today’s Behemoth, the secret life of cells:

Our bodies are made up of some 100 trillion cells. We tend to think of cells as static, because that’s how they were presented to us in textbooks. In fact, the cell is like the most antic, madcap, crowded (yet fantastically efficient) city you can picture. And at its heart lies a mystery—or I should say, several mysteries—involving three special kinds of molecules: DNA, RNA, and proteins.

These molecules are assembled into long chains called polymers, and are uniquely suited for the roles they play. More importantly, life absolutely depends upon them. We have to have DNA, RNA, and protein all present and active at the same time for a living organism to live.

How they work together so optimally and efficiently is not merely amazing, but also a great enigma, a mystery that lies at the heart of life itself. More. Paywall soon after. May be worth it.

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Comments

Sloppy work detected. I apologize for unacceptable errors that have been made when posting research paper references. Using tools like Zotero, which detects repeated entries of the same paper, one can find unintended redundancies. However, sometimes I have skipped that important procedure and may have posted paper references without ensuring duplicate instances of the same quoted text. Please, note that in some cases the same paper is referenced in more than one post, but the quoted text is different in each sub-post. That is done intentionally for various reasons. Either to save the post in order to avoid losing it for technical issues that may arise at that moment, or just to reduce the amount of quoted text within a single post, thus making it a little easier to read it. In those intentional cases the posts should appear together, on the same date, one after another. However if the same paper is found referenced in more than one post, but on distant dates, and the quoted text coincides (at least partially) then that could be a mistake. For example, just noticed the article:
Actomyosin ring driven cytokinesis in budding yeast Franz Meitinger, Saravanan Palani doi:10.1016/j.semcdb.2016.01.043 Seminars in Cell & Developmental Biology Volume 53, Pages 19–27 Cytokinetic ring construction and constriction Fibroblast Growth factor signalling
appears referenced twice in this thread but on distant dates: July 3 and September 20 of this year. That's obviously a mistake resulting from not having set the necessary controls and also because I wasn't careful enough to ensure this kind of mistake doesn't happen. Now, all that said, I noticed a kind-of funny thing associated with this embarrassing mistake I made: the quoted text is not quite the same. That seems to indicate that on each separate occasion different parts of the text were selected for the posted quotes. A small portion of the quoted text coincides, but the rest are different. That may tell us that the given paper is really juicy. :)
July 3, 2016 at 2:28 pm Cytokinesis is the final process in the cell cycle that physically divides one cell into two. […] cytokinesis is driven by a contractile actomyosin ring (AMR) and the simultaneous formation of a primary septum, which serves as template for cell wall deposition. AMR assembly, constriction, primary septum formation and cell wall deposition are successive processes and tightly coupled to cell cycle progression to ensure the correct distribution of genetic material and cell organelles among the two rising cells prior to cell division. The role of the AMR in cytokinesis and the molecular mechanisms that drive AMR constriction and septation are the focus of current research. […] cells have […] robust systems that ensure high fidelity in coordinating cell division processes. Research over the last two decades has identified essential components of the cell division machinery as well as their complex interactions throughout the cell cycle. Structural information, investigations into the molecular mechanisms and of key and regulatory components have given insight into how the AMR drives cytokinesis. However, we do not completely understand the basic mechanisms that drive and coordinate AMR constriction and septum formation. A future milestone in the field will be to establish an in vitro system that is able to simulate in vivo characteristics of the cell division machinery. This would allow one to investigate the underlying mechanisms in a fully tunable manner. In vivo evidence has demonstrated that the formation of extracellular matrix and the involved membrane associated proteins might be essential for the function of the AMR and even for its assembly. The implementation of these aspects in an in vitro system will be challenging.

September 20, 2016 at 1:27 am […] we do not completely understand the basic mechanisms that drive and coordinate AMR constriction and septum formation. The role of the AMR in cytokinesis and the molecular mechanisms that drive AMR constriction and septation are the focus of current research. […] how budding yeast cells orchestrate the multitude of molecular mechanisms that control AMR driven cytokinesis in a spatio-temporal manner to achieve an error free cell division. [?] […] the function of the AMR is optimized to meet the special requirements of the particular organism/cell type. […] the complex network of interactions between the plasma membrane and the AMR could form redundancy to provide a certain amount of robustness to the system. How the actin cables are organized in budding yeast is unknown and comparative studies have not been performed to date. How Mlc2 contributes to AMR constriction is not currently understood. The motor domain of Myo1, the regulatory myosin light chain Mlc2 and actin dynamics clearly contribute to AMR constriction. The molecular mechanism of the latter two and which role the primary septum plays remains to be fully elucidated. It is unclear why the AMR breaks in Inn1 or Chs2 deficient mutants that cannot form a primary septum […] […] efficient AMR constriction and primary septum formation are interdependent. Whether Rho1 directly regulates cell cleavage is not known. Rho1 is in addition to its function in AMR assembly the major regulator of secondary septum formation. This requires sequential Rho1 activation and inhibition steps in a spatiotemporal manner to allow the successive formation of the AMR and secondary septum and subsequent cell separation.
Please, post a comment with a warning about another duplicate case (quoted text overlap) that you may encounter here. Simply indicate the post numbers so I can review them. Thank you. I'll try hard to prevent this from happening again.Dionisio_{October 31, 2016
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#2170 addendum butifnot October 9, 2016 at 3:01 amDionisio_{October 29, 2016
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For survival and growth, bacteria move in liquid environment by rotating a long filamentous organelle, the flagellum. The bacterial flagellum is a huge extracellular assembly composed of more than 20,000 subunits of about 30 different proteins. Most of the component proteins are translocated into the central channel of the growing flagellum via the flagellar protein export apparatus driven by proton motive force and ATP hydrolysis, and go through the channel to the growing tip for their assembly.
Insight into the flagella type III export revealed by the complex structure of the type III ATPase and its regulator Katsumi Imada,a,1,2 Tohru Minamino,b,1 Yumiko Uchida,a Miki Kinoshita,a,b and Keiichi Namba Proc Natl Acad Sci U S A. 113(13): 3633–3638. doi: 10.1073/pnas.1524025113 PMCID: PMC4822572 Microbiology

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[...] the structure of the complex between FlgN and its substrates is not known [...] When it is time for FliD to be exported, FliT binds and escorts FliD to the membrane for its export and the assembly of the filament-capping structure.
Proc Natl Acad Sci U S A. 113(35):9798-803. doi: 10.1073/pnas.1607845113. Recognition and targeting mechanisms by chaperones in flagellum assembly and operation. Khanra N1, Rossi P1, Economou A2, Kalodimos CG3.

How does it determine when it's time to act?Dionisio_{October 29, 2016
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The classical paradigm states that the structure of a protein is related to its function. However, it has been shown that at least 30% of the human genome has no specific structure, including the whole gene or part of it, and that these regions generally bind to other proteins or DNA [...] IDPs behave very differently than globular proteins, leading to a complex regulation of the mechanism of protein-protein recognition by changes in protein conformation. Our results are in agreement with previous experimental studies, allowing a clear picture of how p53 is regulated by phosphorylation and giving new insights into how post-translational modifications can regulate the function of IDPs.
Phosphorylation Regulates the Bound Structure of an Intrinsically Disordered Protein: The p53-TAZ2 Case. Ithuralde RE, Turjanski AG PLoS One. 11(1):e0144284. doi: 10.1371/journal.pone.0144284.

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Post-translational modifications (PTMs) produce significant changes in the structural properties of intrinsically disordered proteins (IDPs) by affecting their energy landscapes. PTMs can induce a range of effects, from local stabilization or destabilization of transient secondary structure to global disorder-to-order transitions, potentially driving complete state changes between intrinsically disordered and folded states or dispersed monomeric and phase-separated states.
Modulation of Intrinsically Disordered Protein Function by Post-translational Modifications. Bah A, Forman-Kay JD. J Biol Chem. 291(13):6696-705. doi: 10.1074/jbc.R115.695056.

Dionisio_{October 29, 2016
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Biologically active but floppy proteins represent a new reality of modern protein science. These intrinsically disordered proteins (IDPs) and hybrid proteins containing ordered and intrinsically disordered protein regions (IDPRs) constitute a noticeable part of any given proteome. Functionally, they complement ordered proteins, and their conformational flexibility and structural plasticity allow them to perform impossible tricks and be engaged in biological activities that are inaccessible to well folded proteins with their unique structures. [...] despite their simplified amino acid sequences, IDPs/IDPRs are complex entities often resembling chaotic systems, are structurally and functionally heterogeneous, and can be considered an important part of the structure-function continuum. Furthermore, IDPs/IDPRs are everywhere, and are ubiquitously engaged in various interactions characterized by a wide spectrum of binding scenarios and an even wider spectrum of structural and functional outputs.
Dancing Protein Clouds: The Strange Biology and Chaotic Physics of Intrinsically Disordered Proteins. Uversky VN1. J Biol Chem. 291(13):6681-8. doi: 10.1074/jbc.R115.685859.

Dionisio_{October 29, 2016
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The process of DNA segregation is a crucial stage of the bacterial cell cycle and it depends on the precise coordination with other cellular events. [...] pSM19035 and TP228 despite sharing the same type Ib partitioning system employ distinct segregation mechanisms. [...] which event occurs first? If ParR assembly into a super-helical structure occurs first, then the macromolecular complex may recruit parC. Otherwise, the centromere might function as a scaffold for ParR oligomerization. TubY seems to be a regulator protein that modulates TubZ assembly (Oliva et al., 2012) and also acts as a transcriptional activator (Ge et al., 2014b) but the exact molecular mechanisms remain elusive. It is still common for new partitioning systems to be discovered in plasmids, phages, and on chromosomes. Together with a growing body of molecular insights these will help to broaden our understanding of DNA trafficking during bacterial cell division and in particular how DNA is attached to the CBP during segrosome formation and then to the motor protein through the segrosome.
Segrosome Complex Formation during DNA Trafficking in Bacterial Cell Division María A. Oliva Front Mol Biosci. 3: 51. doi: 10.3389/fmolb.2016.00051

Dionisio_{October 29, 2016
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gpuccio: Thank you for writing such an encouraging and supportive message, which has additional value because it comes from someone who has unambiguously promoted the fascinating concept of biological controlling procedures and has demonstrated genuine passion for keeping biology research truthful and humble. I've learned much from your insightful articles and commentaries. I look forward to reading more of your interesting OPs in the days ahead. I know you're serious about what you write, hence it takes time to produce a valuable article on such a complex topic as the controlling procedures underlying the multilevel regulatory networks and signaling pathways orchestrated within the marvelous biological systems we observe. Please, keep working on it and delight us with another juicy article to discuss. I'm also working intensively on gathering as much information as I can and will try to share the most interesting ones with the serious readers in this site. This is also a humbling learning experience for me.Dionisio_{October 29, 2016
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Dionisio: Your contributions on this thread are one of the best things happening at UD! Please, go on with your wonderful work. :)gpuccio_{October 28, 2016
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#2169 addendum Pindi September 1, 2016 at 9:41 pm Pindi September 2, 2016 at 2:34 am Both posts were about irrelevant issues unrelated to science.Dionisio_{October 28, 2016
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Here are some (not all) participants in this thread: bornagain77 December 21, 2014 at 10:34 am bornagain77 December 21, 2014 at 1:14 pm bornagain77 December 21, 2014 at 1:15 pm bornagain77 December 23, 2014 at 9:19 pm bornagain77 December 24, 2014 at 6:20 pm bornagain77 June 21, 2015 at 7:50 am bornagain77 June 21, 2015 at 7:51 am bornagain77 June 21, 2015 at 7:52 am bornagain77 July 3, 2015 at 12:54 pm Axel December 21, 2014 at 12:20 pm Axel January 7, 2015 at 8:43 am Seversky December 21, 2014 at 1:01 pm Seversky December 23, 2014 at 7:48 pm Seversky December 24, 2014 at 5:36 pm Seversky December 24, 2014 at 5:50 pm mahuna December 21, 2014 at 3:33 pm PeterJ December 23, 2014 at 1:04 am Quest January 1, 2015 at 9:38 am AVS January 7, 2015 at 2:19 pm AVS January 7, 2015 at 3:09 pm AVS January 7, 2015 at 4:01 pm AVS January 7, 2015 at 4:15 pm Joe January 7, 2015 at 7:32 pm gpuccio January 7, 2015 at 6:22 am gpuccio January 7, 2015 at 6:28 am gpuccio January 8, 2015 at 6:31 am gpuccio February 14, 2015 at 6:40 am gpuccio October 31, 2015 at 1:03 am gpuccio October 31, 2015 at 4:16 am gpuccio November 17, 2015 at 7:12 am gpuccio November 17, 2015 at 10:26 am gpuccio November 29, 2015 at 6:13 am gpuccio December 2, 2015 at 5:38 am gpuccio December 2, 2015 at 10:43 am gpuccio December 16, 2015 at 6:39 am gpuccio July 14, 2016 at 2:41 am gpuccio July 14, 2016 at 8:32 am gpuccio October 1, 2016 at 1:44 am gpuccio October 5, 2016 at 3:26 pm William J Murray February 14, 2015 at 5:45 am Upright BiPed December 16, 2015 at 9:50 am Upright BiPed December 16, 2015 at 2:04 pmDionisio_{October 28, 2016
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Defining the molecular nature of these interactions continues to be an essential step toward the understanding of these intriguing DNA binding proteins.
ParB Partition Proteins: Complex Formation and Spreading at Bacterial and Plasmid Centromeres Barbara E. Funnell Front Mol Biosci. 3: 44. doi: 10.3389/fmolb.2016.00044

Dionisio_{October 27, 2016
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A large segment of the proteome consists of disordered regions, yet in most cases, little is known about their mechanisms and functions. What are the roles of protein disorder in cell biology, and how do intrinsically disordered proteins function?
Cell. 166(5):1074-7. doi: 10.1016/j.cell.2016.08.012. Illuminating the Dark Proteome.

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Large Tumors Destroyed by Innate/Adaptive Immunotherapy Combo http://www.genengnews.com/gen-news-highlights/large-tumors-destroyed-by-innate-adaptive-immunotherapy-combo/81253360

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These clinical data together with the preclinical studies in this report support further clinical investigation of poxvirus-based active immunotherapy with immune checkpoint blockade to address the high unmet need for cancer patients who do not respond to immune checkpoint blockade alone.
Poxvirus-Based Active Immunotherapy with PD-1 and LAG-3 Dual Immune Checkpoint Inhibition Overcomes Compensatory Immune Regulation, Yielding Complete Tumor Regression in Mice. Foy SP1, Sennino B1, dela Cruz T1, Cote JJ1, Gordon EJ1, Kemp F1, Xavier V1, Franzusoff A1, Rountree RB1, Mandl SJ1. PLoS One. 11(2):e0150084. doi: 10.1371/journal.pone.0150084.

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Checkpoint blockade with antibodies specific for cytotoxic T lymphocyte-associated protein (CTLA)-4 or programmed cell death 1 (PDCD1; also known as PD-1) elicits durable tumor regression in metastatic cancer, but these dramatic responses are confined to a minority of patients. This suboptimal outcome is probably due in part to the complex network of immunosuppressive pathways present in advanced tumors, which are unlikely to be overcome by intervention at a single signaling checkpoint. These results demonstrate the capacity of an elicited endogenous immune response to destroy large, established tumors and elucidate essential characteristics of combination immunotherapies that are capable of curing a majority of tumors in experimental settings typically viewed as intractable.
Eradication of large established tumors in mice by combination immunotherapy that engages innate and adaptive immune responses. Moynihan KD1,2,3, Opel CF1,4, Szeto GL1,2,3, Tzeng A1,2, Zhu EF1,4, Engreitz JM5,6, Williams RT7, Rakhra K1, Zhang MH1, Rothschilds AM1,2, Kumari S1, Kelly RL1,2, Kwan BH1,2, Abraham W1, Hu K2, Mehta NK1,2, Kauke MJ1,4, Suh H1, Cochran JR8,9,10, Lauffenburger DA1,2,3, Wittrup KD1,2,4, Irvine DJ Nat Med. 2016 doi: 10.1038/nm.42

Dionisio_{October 27, 2016
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The three stop codons UAA, UAG, and UGA signal the termination of mRNA translation. As a result of a mechanism that is not adequately understood, they are normally used with unequal frequencies. In highly expressed genes stop codon usage is compositionally and structurally consistent with highly efficient translation termination signals. The causes of the uneven use of synonymous codons, named codon usage bias or codon bias, are not yet fully understood. The strong relationship between stop codon identity and base context of the proximal 3’-UTR can be explained by a common structural function related with the efficiency of translation termination, or with functional activities connected with processes involving mRNA metabolism.
Selective forces and mutational biases drive stop codon usage in the human genome: a comparison with sense codon usage Edoardo Trotta BMC Genomics. 17: 366. doi: 10.1186/s12864-016-2692-4

Dionisio_{October 22, 2016
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Understanding the regulatory mechanisms controlling how DNA is converted to RNA, which is then translated into protein sequences, is a key challenge in molecular biology. [...] prokaryotes and single-cell eukaryotes can actively regulate protein expression levels by adjusting codon usage and tRNA anticodon abundance [...] Whether codon usage is used to fine-tune levels of protein translation in mammals is actively debated. [...] the rate at which a protein can be synthesized from an mRNA is influenced by the relationship between tRNA anticodon abundance and codon frequency within the mRNA. [...] orphan codons that lack a corresponding tRNA are decoded using non-canonical pairing between codons and anticodons, commonly referred to as wobble base pairing [...] [...] the extent to which each codon is translated by a specific tRNA via wobble base pairing differs between species [...] [...] the mammalian genome is better optimized for complex transcriptional and post-transcriptional regulation [...] [...] prokaryotes and mammals differ in the extent to which translational efficiency and codon biases are relied upon as a regulatory mechanism.
Codon-Driven Translational Efficiency Is Stable across Diverse Mammalian Cell States Konrad L. M. Rudolph,#1 Bianca M. Schmitt,#2 Diego Villar,2 Robert J. White,3 John C. Marioni,1,2,4,* Claudia Kutter,2,5,* and Duncan T. Odom2,4,* Nicolas Galtier, Editor PLoS Genet. 12(5): e1006024. doi: 10.1371/journal.pgen.1006024

Dionisio_{October 22, 2016
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Whether codon usage fine-tunes mRNA translation in mammals remains controversial, with recent papers suggesting that production of proteins in specific Gene Ontological (GO) pathways can be regulated by actively modifying the codon and anticodon pools in different cellular conditions. GC variation across the mammalian genome is most likely a result of the interplay between genome repair and gene duplication mechanisms, rather than selective pressures caused by codon-driven translational rates. Consequently, codon usage differences in mammalian transcriptomes are most easily explained by well-understood mutational biases acting on the underlying genome.
Codon-Driven Translational Efficiency Is Stable across Diverse Mammalian Cell States Konrad L. M. Rudolph,#1 Bianca M. Schmitt,#2 Diego Villar,2 Robert J. White,3 John C. Marioni,1,2,4,* Claudia Kutter,2,5,* and Duncan T. Odom2,4,* Nicolas Galtier, Editor PLoS Genet. 12(5): e1006024. doi: 10.1371/journal.pgen.1006024

Dionisio_{October 22, 2016
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The expression of a gene is a tightly regulated process and is exerted by a myriad of different mechanisms. [...] mRNA modifications are a powerful mechanism to post-transcriptionally regulate gene expression. Regulation of gene expression is a complex multistep process. The synthesis of a functional protein is subject to several layers of regulation, starting from the synthesis of various transcription factors up to the correct assembly of the nascent protein by chaperones. [...] the site-specific incorporation of modified RNA nucleotides into coding regions of mRNAs revealed astonishingly versatile effects on protein synthesis depending not only on the type of the RNA modification but also on the codon position [...] [...] it is of utmost importance to elucidate all mechanisms behind. [...] many aspects of mRNA modifications are still far from being completely understood. Elucidating the regulation of mRNA modifications and their cellular functions will open up a completely new way in understanding gene regulation on the level of RNA.
mRNA modifications: Dynamic regulators of gene expression? Thomas Philipp Hoernes, Alexander Hüttenhofer, and Matthias David Erlacher RNA Biol. 13(9): 760–765. doi: 10.1080/15476286.2016.1203504

Dionisio_{October 22, 2016
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The different triplets encoding the same amino acid, termed as synonymous codons, are not equally abundant in a genome. It is likely that the order of the nucleotides in the triplet codon is also perhaps involved in the phenomenon of codon usage bias in organisms. [...] our study indicates a vital role of the nucleotide sequence of the triplet in selection as OCs in bacteria [...] More research on codon–anticodon pairing during translation is likely to provide empirical evidence in favour of the role of codon–anticodon interaction on the selection of OCs.
Discrepancy among the synonymous codons with respect to their selection as optimal codon in bacteria Siddhartha Sankar Satapathy,1 Bhesh Raj Powdel,2 Alak Kumar Buragohain,3,4 and Suvendra Kumar Ray3,* DNA Res. 23(5): 441–449. doi: 10.1093/dnares/dsw027

Dionisio_{October 22, 2016
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Recent evidence provides strong support for the idea that cells use tRNA to dynamically regulate gene expression in response to stress. [...] reprogrammed tRNAs are involved in the selective translation of proteins from families of genes in which there is a second genetic code, in the form of a biased use of degenerate codons. The identification of stress-induced changes in tRNA modification, codon-biased translation, and MoTTs supports the idea that cells use distinct translational programs during stress responses. As a corollary to translational up-regulation of stress response proteins, it is likely that stress-induced changes in tRNA modification will cause significant down-regulation in the translation groups of codon-biased transcripts, as an efficient means to shut down specific activities as the cell alters phenotype to survive the stress. Ongoing studies will test these models and other features of the translational control of cell stress response. [...] tools will yield important new insights into the role of translational elongation in cell stress response.
Codon-biased translation can be regulated by wobble-base tRNA modification systems during cellular stress responses Lauren Endres,1 Peter C Dedon,2,3,* and Thomas J Begley1,4,* RNA Biol. 12(6): 603–614. doi: 10.1080/15476286.2015.1031947

Dionisio_{October 22, 2016
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[...] the mechanism by which amino acids activate Vps34 remained unclear. It is not clear how LRS regulation of Vps34-PLD can be reconciled with the reported LRS regulation of Rag [...] [...] it is possible that other factors may be involved in amino acid-sensing and/or signal transduction by LRS in the cytosol, which warrant future investigations.
Leucyl-tRNA synthetase activates Vps34 in amino acid-sensing mTORC1 signaling Mee-Sup Yoon,1,2,†* Kook Son,1,† Edwin Arauz,1 Jung Min Han,3,4 Sunghoon Kim,5 and Jie Chen Cell Rep. 16(6): 1510–1517. doi: 10.1016/j.celrep.2016.07.008

Dionisio_{October 21, 2016
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While such global translational repression was observed many decades ago, its functional significance remains unknown. [...] it is unclear whether IRES-dependent translation represents a general mechanism of translational regulation during mitosis, and whether such IRES-dependent translational activation represents, a minor, or the dominant mechanism of gene-specific translational regulation during mitosis. [...] translational regulation can enhance the efficiency of post-translational protein inhibition, which may represent a more general function for translational repression. [...] together these studies provide a complete overview of translational regulation during the cell cycle.
Regulation of mRNA translation during mitosis Marvin E Tanenbaum,1 Noam Stern-Ginossar,1,2,3 Jonathan S Weissman,1,2,3 and Ronald D Vale1,* eLife. 4: e07957. doi: 10.7554/eLife.07957

Dionisio_{October 21, 2016
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Passage through mitosis is driven by precisely-timed changes in transcriptional regulation and protein degradation. However, the importance of translational regulation during mitosis remains poorly understood. [...] it is not clear whether regulation of translation is involved in control of the cell division. These findings uncover a new role for the control of protein production in regulating the cell cycle. The next challenge will be to find out whether suppression of translation is also used in other biological systems where proteins need to be rapidly inactivated.
Regulation of mRNA translation during mitosis Marvin E Tanenbaum,1 Noam Stern-Ginossar,1,2,3 Jonathan S Weissman,1,2,3 and Ronald D Vale1,* eLife. 4: e07957. doi: 10.7554/eLife.07957

Dionisio_{October 21, 2016
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Translation is an essential step in gene expression. The reasons for this phenomenon are at present unclear. It could be that these switches are regulated. In the future, it will be interesting to analyze mRNAs regulated at the translational level. Future studies will be thus required to understand the functions of the DYNC1H1 translation factories. In the future, it will be interesting to determine whether these correspond to translation factories or to sites of accumulation of untranslated mRNA, as in the case of P-bodies. It would also be interesting to determine whether the accumulation of mRNAs in foci is linked to a specific transport pathway that may help to deliver them when and where they are needed.
Visualization of single endogenous polysomes reveals the dynamics of translation in live human cells. Pichon X1, Bastide A2, Safieddine A2, Chouaib R2, Samacoits A3, Basyuk E2, Peter M2, Mueller F3, Bertrand E1. J Cell Biol. 214(6):769-81. doi: 10.1083/jcb.201605024.

Dionisio_{October 20, 2016
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Translation is under tight spatial and temporal controls to ensure protein production in the right time and place in cells.
Real-Time Imaging of Translation on Single mRNA Transcripts in Live Cells. Wang C, Han B1, Zhou R, Zhuang X Cell. 165(4):990-1001. doi: 10.1016/j.cell.2016.04.040.

Dionisio_{October 20, 2016
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Translation is the fundamental biological process converting mRNA information into proteins. [...] the translation of localized mRNA in living cells remains poorly understood [...] Further development will be needed to study translation of endogenous genes. This technology provides a tool with which to address the spatiotemporal translation mechanism of single mRNAs in living cells.
Translation dynamics of single mRNAs in live cells and neurons Bin Wu, Carolina Eliscovich, Young J. Yoon and Robert H. Singer Science. 352(6292): 1430–1435. doi: 10.1126/science.aaf1084

Dionisio_{October 20, 2016
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Future studies using the SunTag approach will illuminate the range of variation on endogenous mRNAs. As tracking of single molecules by fluorescence microscopy gets more attainable, three-color studies tracking a transcript, its translation, and trans factors will lead to great insight into the function and timing of trans factors in regulating translation. [...] there is wide variability within and between mRNA populations. Whether this variability is stochastic or represents differential regulation among the individual mRNAs remains to be seen.
A beacon in the cytoplasm: Tracking translation of single mRNAs. Pingali HV, Hilliker AK. J Cell Biol. 214(6):649-52. doi: 10.1083/jcb.201608075.

Complex complexity.Dionisio_{October 19, 2016
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19
19
2016
08:01 PM
8
08
01
PM
PDT}

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