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1.
Radiol Case Rep ; 18(4): 1452-1456, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36798062

ABSTRACT

Tumor-to-tumor metastasis is a rare event with meningioma as the recipient tumor accounting for 20% of the reported cases. The most common primary cancers showing this phenomenon are lung and breast cancer. Most lung cancers metastasizing to a meningioma are due to lung adenocarcinoma with the literature containing only 3 prior reports of small-cell lung cancer showing this pattern of spread. Herein, we present the case of a 67-year-old-patient with small-cell lung cancer that developed a metastasis to a meningioma.

2.
Nutrients ; 14(19)2022 Oct 10.
Article in English | MEDLINE | ID: mdl-36235865

ABSTRACT

Background: There is evidence that high-fibre diets have significant health benefits, although the effect of increasing fibre on individuals' appetite, satiety, and gastrointestinal comfort is not well established, nor is its acceptability and feasibility. Methods: This mixed-methods feasibility randomised control trial included 38 participants allocated to one of three conditions: FibreMAX (two daily servings of 25 g of BARLEYmax®), FibreGRAD (two daily servings with the amount of fibre gradually increased), and Control (two daily servings totalling 25 g of placebo product). Participants completed a food diary at baseline. The Hunger and Fullness Questionnaire and questions regarding gastrointestinal response were completed at baseline and at the end of each week. Participants completed the acceptability of intervention measure and engaged in a semi-structured interview, following trial completion. Results: The qualitative data suggested that increased fibre influenced appetite and fullness perceptions. Baseline fibre consumption and the method of increased fibre increase did not influence our findings. The qualitative results also indicated that the fibre intake was perceived as beneficial to well-being; it influenced feelings of hunger and caused some minor acute gastrointestinal symptoms that dissipated after a short adaption period. Conclusion: This study suggests that increasing fibre intake through BARLEYmax® is a safe intervention that is acceptable to participants.


Subject(s)
Appetite , Satiation , Cross-Over Studies , Dietary Fiber , Energy Intake , Feasibility Studies , Humans , Hunger
3.
Sex Reprod Health Matters ; 29(3): 2005283, 2021.
Article in English | MEDLINE | ID: mdl-34928198

ABSTRACT

Cervical cancer is preventable and curable yet causes almost 2000 deaths in Nepali women each year. The present study aims to explore the feasibility and acceptability of a self-sampling-based approach for cervical cancer screening in urban and peri-urban Nepal and develop pathways for self-sampling using a co-design methodology. An iterative design approach was applied. Semi-structured in-depth interviews were conducted with 30 healthy women and four women who had had a prior cancer diagnosis on topics which included: sexual and reproductive health knowledge and human papillomavirus (HPV); use of the internet/social media platforms; their views regarding acceptability and usability of the self-sampling kit and the proposed user journey. Data collection was done between December 2020 and January 2021. Seven medical experts were also interviewed to explore the current service configuration for cervical cancer screening in Nepal. Knowledge regarding HPV and its association with cervical cancer was absent for the majority of participants. Although 70% (n = 21/30) had purchased items online previously, there was a general lack of trust in online shopping. Half of the women (n = 17/30; 56.7%) expressed a willingness to self-sample and provided recommendations to improve the clarity of the instructions. The proposed user journey was considered feasible in the urban area. There is a clear unmet need for information about HPV and alternative cervical screening options in Nepal. An online pathway for self-sampling service delivery to urban women is feasible but will need to be optimally designed to address barriers such as confidence in self-sampling and trust in online purchasing.


Subject(s)
Alphapapillomavirus , Uterine Cervical Neoplasms , Early Detection of Cancer , Feasibility Studies , Female , Humans , Nepal , Papillomaviridae , Uterine Cervical Neoplasms/diagnosis
4.
Behav Processes ; 192: 104475, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34375727

ABSTRACT

Individuals often face unpredictable and harsh environments, presenting them with novel ecological problems. Behaviour can provide an adaptive response in such conditions and where these conditions vary between populations, we may predict development and evolution to shape differences in behaviour such as exploration, innovation, and learning, as well as other traits. Here, we compared in the wild the maze swimming performance of groups of female guppies from two Trinidadian populations that differ in numerous ecological characteristics, the Upper and Lower Aripo river. Compared to Upper Aripo fish, Lower Aripo fish were slower to complete the maze, our measure of propensity to innovate, and scored lower on a combined measure of activity and exploration. More active-exploratory groups were faster to complete the maze, but only in the Lower Aripo. We found no evidence for learning the maze. Our results suggest that activity-exploratory and innovative propensities can vary between populations, as can predictors of innovation. These findings are consistent with high predation risk shaping decreased activity-exploratory propensities, but further population comparisons are required to reliably determine the drivers of the observed population difference. Our results emphasize that individual and population differences in activity-exploration and innovation can be shaped by numerous factors.


Subject(s)
Poecilia , Animals , Biological Evolution , Female , Humans , Phenotype , Predatory Behavior , Swimming
5.
BMC Biochem ; 19(1): 9, 2018 11 12.
Article in English | MEDLINE | ID: mdl-30419808

ABSTRACT

BACKGROUND: Islet amyloid polypeptide (IAPP) or amylin deposits can be found in the islets of type 2 diabetes patients. The peptide is suggested to be involved in the etiology of the disease through formation of amyloid deposits and destruction of ß islet cells, though the underlying molecular events leading from IAPP deposition to ß cell death are still largely unknown. RESULTS: We used OFFGEL™ proteomics to study how IAPP exposure affects the proteome of rat pancreatic insulinoma Rin-5F cells. The OFFGEL™ methodology is highly effective at generating quantitative data on hundreds of proteins affected by IAPP, with its accuracy confirmed by In Cell Western and Quantitative Real Time PCR results. Combining data on individual proteins identifies pathways and protein complexes affected by IAPP. IAPP disrupts protein synthesis and degradation, and induces oxidative stress. It causes decreases in protein transport and localization. IAPP disrupts the regulation of ubiquitin-dependent protein degradation and increases catabolic processes. IAPP causes decreases in protein transport and localization, and affects the cytoskeleton, DNA repair and oxidative stress. CONCLUSIONS: Results are consistent with a model where IAPP aggregates overwhelm the ability of a cell to degrade proteins via the ubiquitin system. Ultimately this leads to apoptosis. IAPP aggregates may be also toxic to the cell by causing oxidative stress, leading to DNA damage or by decreasing protein transport. The reversal of any of these effects, perhaps by targeting proteins which alter in response to IAPP, may be beneficial for type II diabetes.


Subject(s)
Islet Amyloid Polypeptide/pharmacology , Proteome/drug effects , Animals , Cell Line, Tumor , Cell Survival/drug effects , Chromatography, High Pressure Liquid , DNA Repair/drug effects , Gene Expression Regulation/drug effects , Humans , Mass Spectrometry , Oxidative Stress/drug effects , Proteome/genetics , Proteome/metabolism , Rats
6.
Sci Rep ; 8(1): 7949, 2018 05 21.
Article in English | MEDLINE | ID: mdl-29785040

ABSTRACT

The transcriptional responses of yeast cells to diverse stresses typically include gene activation and repression. Specific stress defense, citric acid cycle and oxidative phosphorylation genes are activated, whereas protein synthesis genes are coordinately repressed. This view was achieved from comparative transcriptomic experiments delineating sets of genes whose expression greatly changed with specific stresses. Less attention has been paid to the biological significance of 1) consistent, albeit modest, changes in RNA levels across multiple conditions, and 2) the global gene expression correlations observed when comparing numerous genome-wide studies. To address this, we performed a meta-analysis of 1379 microarray-based experiments in yeast, and identified 1388 blocks of RNAs whose expression changes correlate across multiple and diverse conditions. Many of these blocks represent sets of functionally-related RNAs that act in a coordinated fashion under normal and stress conditions, and map to global cell defense and growth responses. Subsequently, we used the blocks to analyze novel RNA-seq experiments, demonstrating their utility and confirming the conclusions drawn from the meta-analysis. Our results provide a new framework for understanding the biological significance of changes in gene expression: 'archetypal' transcriptional blocks that are regulated in a concerted fashion in response to external stimuli.


Subject(s)
Gene Expression Regulation, Fungal , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae/genetics , Stress, Physiological , Transcription, Genetic , Gene Expression Profiling , Meta-Analysis as Topic , Saccharomyces cerevisiae Proteins/metabolism
7.
Genome Biol ; 18(1): 201, 2017 10 27.
Article in English | MEDLINE | ID: mdl-29078784

ABSTRACT

BACKGROUND: Translation factors eIF4E and eIF4G form eIF4F, which interacts with the messenger RNA (mRNA) 5' cap to promote ribosome recruitment and translation initiation. Variations in the association of eIF4F with individual mRNAs likely contribute to differences in translation initiation frequencies between mRNAs. As translation initiation is globally reprogrammed by environmental stresses, we were interested in determining whether eIF4F interactions with individual mRNAs are reprogrammed and how this may contribute to global environmental stress responses. RESULTS: Using a tagged-factor protein capture and RNA-sequencing (RNA-seq) approach, we have assessed how mRNA associations with eIF4E, eIF4G1 and eIF4G2 change globally in response to three defined stresses that each cause a rapid attenuation of protein synthesis: oxidative stress induced by hydrogen peroxide and nutrient stresses caused by amino acid or glucose withdrawal. We find that acute stress leads to dynamic and unexpected changes in eIF4F-mRNA interactions that are shared among each factor and across the stresses imposed. eIF4F-mRNA interactions stabilised by stress are predominantly associated with translational repression, while more actively initiating mRNAs become relatively depleted for eIF4F. Simultaneously, other mRNAs are insulated from these stress-induced changes in eIF4F association. CONCLUSION: Dynamic eIF4F-mRNA interaction changes are part of a coordinated early translational control response shared across environmental stresses. Our data are compatible with a model where multiple mRNA closed-loop complexes form with differing stability. Hence, unexpectedly, in the absence of other stabilising factors, rapid translation initiation on mRNAs correlates with less stable eIF4F interactions.


Subject(s)
Eukaryotic Initiation Factor-4F/metabolism , Peptide Chain Initiation, Translational , RNA, Messenger/metabolism , Stress, Physiological/genetics , Ribosomes/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism
11.
Clin Cancer Res ; 22(3): 680-90, 2016 Feb 01.
Article in English | MEDLINE | ID: mdl-26832745

ABSTRACT

PURPOSE: Aldesleukin, recombinant human IL2, is an effective immunotherapy for metastatic melanoma and renal cancer, with durable responses in approximately 10% of patients; however, severe side effects limit maximal dosing and thus the number of patients able to receive treatment and potential cure. NKTR-214 is a prodrug of conjugated IL2, retaining the same amino acid sequence as aldesleukin. The IL2 core is conjugated to 6 releasable polyethylene glycol (PEG) chains. In vivo, the PEG chains slowly release to generate active IL2 conjugates. EXPERIMENTAL DESIGN: We evaluated the bioactivity and receptor binding of NKTR-214 and its active IL2 conjugates in vitro; the tumor immunology, tumor pharmacokinetics, and efficacy of NKTR-214 as a single agent and in combination with anti-CTLA-4 antibody in murine tumor models. Tolerability was evaluated in non-human primates. RESULTS: In a murine melanoma tumor model, the ratio of tumor-killing CD8(+) T cells to Foxp3(+) regulatory T cells was greater than 400 for NKTR-214 compared with 18 for aldesleukin, supporting preferential activation of the IL2 receptor beta over IL2 receptor alpha, due to the location of PEG molecules. NKTR-214 provides a 500-fold greater exposure of the tumor to conjugated IL2 compared with aldesleukin. NKTR-214 showed efficacy as a single agent and provided durable immunity that was resistant to tumor rechallenge in combination with anti-CTLA-4 antibody. NKTR-214 was well tolerated in non-human primates. CONCLUSIONS: These data support further evaluation of NKTR-214 in humans for a variety of tumor types, adding to the repertoire of potent and potentially curative cancer immunotherapies.


Subject(s)
Antineoplastic Agents/pharmacology , Interleukin-2/analogs & derivatives , Neoplasms/metabolism , Neoplasms/pathology , Polyethylene Glycols/pharmacology , Prodrugs , Receptors, Interleukin-2/metabolism , Recombinant Fusion Proteins/pharmacology , Animals , Antineoplastic Agents/chemistry , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , CTLA-4 Antigen/antagonists & inhibitors , Cell Line, Tumor , Disease Models, Animal , Drug Synergism , Female , Humans , Immunologic Memory , Interleukin-2/chemistry , Interleukin-2/pharmacology , Lymphocytes, Tumor-Infiltrating , Male , Melanoma, Experimental , Mice , Models, Molecular , Molecular Conformation , Neoplasms/drug therapy , Neoplasms/immunology , Polyethylene Glycols/chemistry , Protein Binding , Receptors, Interleukin-2/chemistry , Recombinant Fusion Proteins/chemistry , Recombinant Proteins/pharmacology , T-Lymphocytes, Regulatory/drug effects , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism , Tumor Burden/drug effects
12.
Mol Cell Proteomics ; 15(4): 1309-22, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26750110

ABSTRACT

Defining intracellular protein concentration is critical in molecular systems biology. Although strategies for determining relative protein changes are available, defining robust absolute values in copies per cell has proven significantly more challenging. Here we present a reference data set quantifying over 1800Saccharomyces cerevisiaeproteins by direct means using protein-specific stable-isotope labeled internal standards and selected reaction monitoring (SRM) mass spectrometry, far exceeding any previous study. This was achieved by careful design of over 100 QconCAT recombinant proteins as standards, defining 1167 proteins in terms of copies per cell and upper limits on a further 668, with robust CVs routinely less than 20%. The selected reaction monitoring-derived proteome is compared with existing quantitative data sets, highlighting the disparities between methodologies. Coupled with a quantification of the transcriptome by RNA-seq taken from the same cells, these data support revised estimates of several fundamental molecular parameters: a total protein count of ∼100 million molecules-per-cell, a median of ∼1000 proteins-per-transcript, and a linear model of protein translation explaining 70% of the variance in translation rate. This work contributes a "gold-standard" reference yeast proteome (including 532 values based on high quality, dual peptide quantification) that can be widely used in systems models and for other comparative studies.


Subject(s)
Mass Spectrometry/methods , Proteomics/methods , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Gene Expression Profiling/methods , Isotope Labeling , Linear Models , Mass Spectrometry/standards , Proteomics/standards , Recombinant Proteins/metabolism , Reproducibility of Results , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae Proteins/genetics , Sequence Analysis, RNA/methods
13.
Sci Rep ; 5: 15518, 2015 Oct 23.
Article in English | MEDLINE | ID: mdl-26493364

ABSTRACT

The PUF family of RNA-binding proteins regulate gene expression post-transcriptionally. Saccharomyces cerevisiae Puf3p is characterised as binding nuclear-encoded mRNAs specifying mitochondrial proteins. Extensive studies of its regulation of COX17 demonstrate its role in mRNA decay. Using integrated genome-wide approaches we define an expanded set of Puf3p target mRNAs and quantitatively assessed the global impact of loss of PUF3 on gene expression using mRNA and polysome profiling and quantitative proteomics. In agreement with prior studies, our sequencing of affinity-purified Puf3-TAP associated mRNAs (RIP-seq) identified mRNAs encoding mitochondrially-targeted proteins. Additionally, we also found 720 new mRNA targets that predominantly encode proteins that enter the nucleus. Comparing transcript levels in wild-type and puf3∆ cells revealed that only a small fraction of mRNA levels alter, suggesting Puf3p determines mRNA stability for only a limited subset of its target mRNAs. Finally, proteomic and translatomic studies suggest that loss of Puf3p has widespread, but modest, impact on mRNA translation. Taken together our integrated multi-omics data point to multiple classes of Puf3p targets, which display coherent post-transcriptional regulatory properties and suggest Puf3p plays a broad, but nuanced, role in the fine-tuning of gene expression.


Subject(s)
Gene Expression , RNA-Binding Proteins/physiology , Saccharomyces cerevisiae Proteins/physiology , Genes, Fungal , RNA, Messenger/genetics , RNA-Binding Proteins/genetics , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae Proteins/genetics
14.
PLoS Genet ; 11(5): e1005233, 2015 May.
Article in English | MEDLINE | ID: mdl-25973932

ABSTRACT

Translation initiation factor eIF4E mediates mRNA selection for protein synthesis via the mRNA 5'cap. A family of binding proteins, termed the 4E-BPs, interact with eIF4E to hinder ribosome recruitment. Mechanisms underlying mRNA specificity for 4E-BP control remain poorly understood. Saccharomyces cerevisiae 4E-BPs, Caf20p and Eap1p, each regulate an overlapping set of mRNAs. We undertook global approaches to identify protein and RNA partners of both 4E-BPs by immunoprecipitation of tagged proteins combined with mass spectrometry or next-generation sequencing. Unexpectedly, mass spectrometry indicated that the 4E-BPs associate with many ribosomal proteins. 80S ribosome and polysome association was independently confirmed and was not dependent upon interaction with eIF4E, as mutated forms of both Caf20p and Eap1p with disrupted eIF4E-binding motifs retain ribosome interaction. Whole-cell proteomics revealed Caf20p mutations cause both up and down-regulation of proteins and that many changes were independent of the 4E-binding motif. Investigations into Caf20p mRNA targets by immunoprecipitation followed by RNA sequencing revealed a strong association between Caf20p and mRNAs involved in transcription and cell cycle processes, consistent with observed cell cycle phenotypes of mutant strains. A core set of over 500 Caf20p-interacting mRNAs comprised of both eIF4E-dependent (75%) and eIF4E-independent targets (25%), which differ in sequence attributes. eIF4E-independent mRNAs share a 3' UTR motif. Caf20p binds all tested motif-containing 3' UTRs. Caf20p and the 3'UTR combine to influence ERS1 mRNA polysome association consistent with Caf20p contributing to translational control. Finally ERS1 3'UTR confers Caf20-dependent repression of expression to a heterologous reporter gene. Taken together, these data reveal conserved features of eIF4E-dependent Caf20p mRNA targets and uncover a novel eIF4E-independent mode of Caf20p binding to mRNAs that extends the regulatory role of Caf20p in the mRNA-specific repression of protein synthesis beyond its interaction with eIF4E.


Subject(s)
Epigenetic Repression , Eukaryotic Initiation Factor-4E/metabolism , Gene Expression Regulation, Fungal , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/genetics , Transcription Factors/metabolism , Down-Regulation , Eukaryotic Initiation Factor-4E/genetics , Eukaryotic Initiation Factor-4G/genetics , Eukaryotic Initiation Factor-4G/metabolism , Immunoprecipitation , Membrane Proteins/genetics , Membrane Proteins/metabolism , Open Reading Frames , Protein Binding , Protein Biosynthesis , Proteomics , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA-Binding Proteins , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics , Sequence Analysis, RNA , Tandem Mass Spectrometry , Transcription Factors/genetics
15.
Genome Biol ; 16: 10, 2015 Jan 05.
Article in English | MEDLINE | ID: mdl-25650959

ABSTRACT

BACKGROUND: The selection and regulation of individual mRNAs for translation initiation from a competing pool of mRNA are poorly understood processes. The closed loop complex, comprising eIF4E, eIF4G and PABP, and its regulation by 4E-BPs are perceived to be key players. Using RIP-seq, we aimed to evaluate the role in gene regulation of the closed loop complex and 4E-BP regulation across the entire yeast transcriptome. RESULTS: We find that there are distinct populations of mRNAs with coherent properties: one mRNA pool contains many ribosomal protein mRNAs and is enriched specifically with all of the closed loop translation initiation components. This class likely represents mRNAs that rely heavily on the closed loop complex for protein synthesis. Other heavily translated mRNAs are apparently under-represented with most closed loop components except Pab1p. Combined with data showing a close correlation between Pab1p interaction and levels of translation, these data suggest that Pab1p is important for the translation of these mRNAs in a closed loop independent manner. We also identify a translational regulatory mechanism for the 4E-BPs; these appear to self-regulate by inhibiting translation initiation of their own mRNAs. CONCLUSIONS: Overall, we show that mRNA selection for translation initiation is not as uniformly regimented as previously anticipated. Components of the closed loop complex are highly relevant for many mRNAs, but some heavily translated mRNAs interact poorly with this machinery. Therefore, alternative, possibly Pab1p-dependent mechanisms likely exist to load ribosomes effectively onto mRNAs. Finally, these studies identify and characterize a complex self-regulatory circuit for the yeast 4E-BPs.


Subject(s)
Peptide Chain Initiation, Translational , RNA, Messenger/genetics , Cluster Analysis , Eukaryotic Initiation Factors/metabolism , High-Throughput Nucleotide Sequencing , Immunoprecipitation/methods , Models, Biological , Protein Binding , RNA, Messenger/metabolism , RNA-Binding Proteins/metabolism , Yeasts/genetics , Yeasts/metabolism
16.
PLoS Genet ; 11(1): e1004903, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25569619

ABSTRACT

The mechanisms by which RNA-binding proteins control the translation of subsets of mRNAs are not yet clear. Slf1p and Sro9p are atypical-La motif containing proteins which are members of a superfamily of RNA-binding proteins conserved in eukaryotes. RIP-Seq analysis of these two yeast proteins identified overlapping and distinct sets of mRNA targets, including highly translated mRNAs such as those encoding ribosomal proteins. In paralell, transcriptome analysis of slf1Δ and sro9Δ mutant strains indicated altered gene expression in similar functional classes of mRNAs following loss of each factor. The loss of SLF1 had a greater impact on the transcriptome, and in particular, revealed changes in genes involved in the oxidative stress response. slf1Δ cells are more sensitive to oxidants and RIP-Seq analysis of oxidatively stressed cells enriched Slf1p targets encoding antioxidants and other proteins required for oxidant tolerance. To quantify these effects at the protein level, we used label-free mass spectrometry to compare the proteomes of wild-type and slf1Δ strains following oxidative stress. This analysis identified several proteins which are normally induced in response to hydrogen peroxide, but where this increase is attenuated in the slf1Δ mutant. Importantly, a significant number of the mRNAs encoding these targets were also identified as Slf1p-mRNA targets. We show that Slf1p remains associated with the few translating ribosomes following hydrogen peroxide stress and that Slf1p co-immunoprecipitates ribosomes and members of the eIF4E/eIF4G/Pab1p 'closed loop' complex suggesting that Slf1p interacts with actively translated mRNAs following stress. Finally, mutational analysis of SLF1 revealed a novel ribosome interacting domain in Slf1p, independent of its RNA binding La-motif. Together, our results indicate that Slf1p mediates a translational response to oxidative stress via mRNA-specific translational control.


Subject(s)
Protein Biosynthesis/genetics , RNA-Binding Proteins/genetics , Ribosomes/genetics , Saccharomyces cerevisiae Proteins/genetics , Gene Expression Regulation, Fungal , Hydrogen Peroxide/metabolism , Oxidative Stress/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , RNA-Binding Proteins/biosynthesis , Saccharomyces cerevisiae , Saccharomyces cerevisiae Proteins/biosynthesis , Sequence Analysis, RNA
17.
J Cell Sci ; 127(Pt 6): 1254-62, 2014 Mar 15.
Article in English | MEDLINE | ID: mdl-24424022

ABSTRACT

The relocalization of translationally repressed mRNAs to mRNA processing bodies Pbodies is a key consequence of cellular stress across many systems. Pbodies harbor mRNA degradation components and are implicated in mRNA decay, but the relative timing and control of mRNA relocalization to Pbodies is poorly understood. We used the MS2GFP system to follow the movement of specific endogenous mRNAs in live Saccharomyces cerevisiae cells after nutritional stress. It appears that the relocalization of mRNA to Pbodies after stress is biphasic some mRNAs are present early, whereas others are recruited much later concomitant with recruitment of translation initiation factors, such as eIF4E. We also find that Bfr1p is a latephaselocalizing Pbody protein that is important for the delayed entry of certain mRNAS to Pbodies. Therefore, for the mRNAs tested, relocalization to Pbodies varies both in terms of the kinetics and factor requirements. This work highlights a potential new regulatory juncture in gene expression that would facilitate the overall rationalization of protein content required for adaptation to stress.


Subject(s)
RNA, Fungal/metabolism , RNA, Messenger/metabolism , Repressor Proteins/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Gene Expression Regulation, Fungal , RNA Stability , RNA Transport , Saccharomyces cerevisiae/genetics , Stress, Physiological
18.
Nucleic Acids Res ; 42(2): 1026-41, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24163252

ABSTRACT

In response to stress, the translation of many mRNAs in yeast can change in a fashion discordant with the general repression of translation. Here, we use machine learning to mine the properties of these mRNAs to determine specific translation control signals. We find a strong association between transcripts acutely translationally repressed under oxidative stress and those associated with the RNA-binding protein Puf3p, a known regulator of cellular mRNAs encoding proteins targeted to mitochondria. Under oxidative stress, a PUF3 deleted strain exhibits more robust growth than wild-type cells and the shift in translation from polysomes to monosomes is attenuated, suggesting puf3Δ cells perceive less stress. In agreement, the ratio of reduced:oxidized glutathione, a major antioxidant and indicator of cellular redox state, is increased in unstressed puf3Δ cells but remains lower under stress. In untreated conditions, Puf3p migrates with polysomes rather than ribosome-free fractions, but this is lost under stress. Finally, reverse transcriptase-polymerase chain reaction (RT-PCR) of Puf3p targets following affinity purification shows Puf3p-mRNA associations are maintained or increased under oxidative stress. Collectively, these results point to Puf3p acting as a translational repressor in a manner exceeding the global translational response, possibly by temporarily limiting synthesis of new mitochondrial proteins as cells adapt to the stress.


Subject(s)
Gene Expression Regulation, Fungal , Oxidative Stress/genetics , Protein Biosynthesis , RNA-Binding Proteins/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Gene Deletion , Glutathione/metabolism , Oxidation-Reduction , Polyribosomes/metabolism , RNA, Messenger/metabolism , RNA-Binding Proteins/genetics , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics
19.
Article in English | MEDLINE | ID: mdl-23832197

ABSTRACT

The crystal structure of AdhP, a recombinantly expressed alcohol dehydrogenase from Escherichia coli K-12 (substrain MG1655), was determined to 2.01 Å resolution. The structure, which was solved using molecular replacement, also included the structural and catalytic zinc ions and the cofactor nicotinamide adenine dinucleotide (NAD). The crystals belonged to space group P21, with unit-cell parameters a = 68.18, b = 118.92, c = 97.87 Å, ß = 106.41°. The final R factor and Rfree were 0.138 and 0.184, respectively. The structure of the active site of AdhP suggested a number of residues that may participate in a proton relay, and the overall structure of AdhP, including the coordination to structural and active-site zinc ions, is similar to those of other tetrameric alcohol dehydrogenase enzymes.


Subject(s)
Alcohol Dehydrogenase/chemistry , Alcohol Dehydrogenase/metabolism , Escherichia coli/enzymology , NAD/metabolism , Alcohol Dehydrogenase/genetics , Amino Acid Sequence , Binding Sites , Catalysis , Catalytic Domain , Crystallization , Crystallography, X-Ray , Ethanol/pharmacology , Models, Molecular , Molecular Sequence Data , Protein Conformation , Protons , Sequence Homology, Amino Acid , Zinc/chemistry , Zinc/metabolism
20.
Oral Maxillofac Surg Clin North Am ; 25(3): 367-71, v, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23706930

ABSTRACT

This article discusses the general methods used to assess patients before, during, and after operative procedures, sedation, or general anesthesia by the oral and maxillofacial surgery team. The details about specific disease processes will be discussed in other articles. These methods and modalities are not standards, but are commonly used in offices and clinics in the United States where sedation and anesthesia are provided.


Subject(s)
Ambulatory Surgical Procedures/methods , Anesthesia, Dental/methods , Monitoring, Physiologic/methods , Oral Surgical Procedures/methods , Advanced Cardiac Life Support , Anesthesia Recovery Period , Anesthesia, General/methods , Blood Pressure Monitors , Capnography/instrumentation , Conscious Sedation/methods , Heart Rate/physiology , Humans , Monitoring, Intraoperative/methods , Oximetry/instrumentation , Patient Care Planning , Patient Care Team , Patient Discharge , Perioperative Care , Postoperative Care , Preoperative Care
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