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1.  Tsetse Fly Control in Kenya's Spatially and Temporally Dynamic Control Reservoirs: A Cost Analysis 
Human African trypanosomiasis (HAT) and animal African trypanosomiasis (AAT) are significant health concerns throughout much of sub-Saharan Africa. Funding for tsetse fly control operations has decreased since the 1970s, which has in turn limited the success of campaigns to control the disease vector. To maximize the effectiveness of the limited financial resources available for tsetse control, this study develops and analyzes spatially and temporally dynamic tsetse distribution maps of Glossina subgenus Morsitans populations in Kenya from January 2002 to December 2010, produced using the Tsetse Ecological Distribution Model. These species distribution maps reveal seasonal variations in fly distributions. Such variations allow for the identification of “control reservoirs” where fly distributions are spatially constrained by fluctuations in suitable habitat and tsetse population characteristics. Following identification of the control reservoirs, a tsetse management operation is simulated in the control reservoirs using capital and labor control inputs from previous studies. Finally, a cost analysis, following specific economic guidelines from existing tsetse control analyses, is conducted to calculate the total cost of a nationwide control campaign of the reservoirs compared to the cost of a nationwide campaign conducted at the maximum spatial extent of the fly distributions from January 2002 to December 2010. The total cost of tsetse management within the reservoirs sums to $14,212,647, while the nationwide campaign at the maximum spatial extent amounts to $33,721,516. This savings of $19,508,869 represents the importance of identifying seasonally dynamic control reservoirs when conducting a tsetse management campaign, and, in the process, offers an economical means of fly control and disease management for future program planning.
PMCID: PMC3347470  PMID: 22581989
Tsetse Fly; Kenya; Control Reservoirs; Control Simulation; Cost Analysis; African Trypanosomiasis
2.  Atg13 and FIP200 act independently of Ulk1 and Ulk2 in autophagy induction 
Autophagy  2011;7(12):1424-1433.
Under normal growth conditions the mammalian target of rapamycin complex 1 (mTORC1) negatively regulates the central autophagy regulator complex consisting of Unc-51-like kinases 1/2 (Ulk1/2), focal adhesion kinase family-interacting protein of 200 kDa (FIP200) and Atg13. Upon starvation, mTORC1-mediated repression of this complex is released, which then leads to Ulk1/2 activation. In this scenario, Atg13 has been proposed as an adaptor mediating the interaction between Ulk1/2 and FIP200 and enhancing Ulk1/2 kinase activity. Using Atg13-deficient cells, we demonstrate that Atg13 is indispensable for autophagy induction. We further show that Atg13 function strictly depends on FIP200 binding. In contrast, the simultaneous knockout of Ulk1 and Ulk2 did not have a similar effect on autophagy induction. Accordingly, the Ulk1-dependent phosphorylation sites we identified in Atg13 are expendable for this process. This suggests that Atg13 has an additional function independent of Ulk1/2 and that Atg13 and FIP200 act in concert during autophagy induction.
PMCID: PMC3327613
Atg13; autophagy; FIP200; Ulk1; Ulk2
3.  Medication compliance aids: a qualitative study of users' views 
Despite the rapid rise in the use of multicompartmental compliance aids (MCAs), little is known about the role they play in self-management of medication.
To explore the perceived benefits of MCAs for people using them to manage their own or a relative's medication.
Design of study
Qualitative study using in-depth interviews.
West Northumberland.
Recruitment was via posters and leaflets in general practices and community pharmacies. In-depth interviews were conducted using a topic guide.
Nineteen people were interviewed. Three overarching themes emerged in relation to medicine taking: disruption, organisation, and adherence, which impacted on control. The medication regime had caused disruption to their lives and this had led to the purchase of an MCA. The MCA enabled them to organise their medication, which they believed had improved the efficiency of medicine taking and saved time. Although the MCA did not prompt them to take their medication, they could see whether they had actually taken it or not, which alleviated their anxiety. To meet their individual needs and lifestyles, some had developed broader systems of medication management, incorporating the MCA. For a small cost – the initial outlay for the MCA and time spent loading it – they gained control over the management of their medication and their condition.
This group found the use of an MCA to be beneficial, but advice and support regarding how best to manage their medication and on the most appropriate design to suit their needs would be helpful.
PMCID: PMC3026148  PMID: 21276336
medication adherence; medication systems; qualitative research
4.  TraML—A Standard Format for Exchange of Selected Reaction Monitoring Transition Lists* 
Molecular & Cellular Proteomics : MCP  2011;11(4):R111.015040.
Targeted proteomics via selected reaction monitoring is a powerful mass spectrometric technique affording higher dynamic range, increased specificity and lower limits of detection than other shotgun mass spectrometry methods when applied to proteome analyses. However, it involves selective measurement of predetermined analytes, which requires more preparation in the form of selecting appropriate signatures for the proteins and peptides that are to be targeted. There is a growing number of software programs and resources for selecting optimal transitions and the instrument settings used for the detection and quantification of the targeted peptides, but the exchange of this information is hindered by a lack of a standard format. We have developed a new standardized format, called TraML, for encoding transition lists and associated metadata. In addition to introducing the TraML format, we demonstrate several implementations across the community, and provide semantic validators, extensive documentation, and multiple example instances to demonstrate correctly written documents. Widespread use of TraML will facilitate the exchange of transitions, reduce time spent handling incompatible list formats, increase the reusability of previously optimized transitions, and thus accelerate the widespread adoption of targeted proteomics via selected reaction monitoring.
PMCID: PMC3322582  PMID: 22159873
5.  VectorBase: improvements to a bioinformatics resource for invertebrate vector genomics 
Nucleic Acids Research  2011;40(D1):D729-D734.
VectorBase ( is a NIAID-supported bioinformatics resource for invertebrate vectors of human pathogens. It hosts data for nine genomes: mosquitoes (three Anopheles gambiae genomes, Aedes aegypti and Culex quinquefasciatus), tick (Ixodes scapularis), body louse (Pediculus humanus), kissing bug (Rhodnius prolixus) and tsetse fly (Glossina morsitans). Hosted data range from genomic features and expression data to population genetics and ontologies. We describe improvements and integration of new data that expand our taxonomic coverage. Releases are bi-monthly and include the delivery of preliminary data for emerging genomes. Frequent updates of the genome browser provide VectorBase users with increasing options for visualizing their own high-throughput data. One major development is a new population biology resource for storing genomic variations, insecticide resistance data and their associated metadata. It takes advantage of improved ontologies and controlled vocabularies. Combined, these new features ensure timely release of multiple types of data in the public domain while helping overcome the bottlenecks of bioinformatics and annotation by engaging with our user community.
PMCID: PMC3245112  PMID: 22135296
6.  Discovery of catalytically active orthologues of the Parkinson's disease kinase PINK1: analysis of substrate specificity and impact of mutations 
Open biology  2011;1(3):110012.
Missense mutations of the phosphatase and tensin homolog (PTEN)-induced kinase 1 (PINK1) gene cause autosomal-recessive Parkinson's disease. To date, little is known about the intrinsic catalytic properties of PINK1 since the human enzyme displays such low kinase activity in vitro. We have discovered that, in contrast to mammalian PINK1, insect orthologues of PINK1 we have investigated—namely Drosophila melanogaster (dPINK1), Tribolium castaneum (TcPINK1) and Pediculus humanus corporis (PhcPINK1)—are active as judged by their ability to phosphorylate the generic substrate myelin basic protein. We have exploited the most active orthologue, TcPINK1, to assess its substrate specificity and elaborated a peptide substrate (PINKtide, KKWIpYRRSPRRR) that can be employed to quantify PINK1 kinase activity. Analysis of PINKtide variants reveal that PINK1 phosphorylates serine or threonine, but not tyrosine, and we show that PINK1 exhibits a preference for a proline at the +1 position relative to the phosphorylation site. We have also, for the first time, been able to investigate the effect of Parkinson's disease-associated PINK1 missense mutations, and found that nearly all those located within the kinase domain, as well as the C-terminal non-catalytic region, markedly suppress kinase activity. This emphasizes the crucial importance of PINK1 kinase activity in preventing the development of Parkinson's disease. Our findings will aid future studies aimed at understanding how the activity of PINK1 is regulated and the identification of physiological substrates.
PMCID: PMC3352081  PMID: 22645651
biochemistry; Parkinson's disease; kinase
7.  Absolute quantification of microbial proteomes at different states by directed mass spectrometry 
The developed, directed mass spectrometry workflow allows to generate consistent and system-wide quantitative maps of microbial proteomes in a single analysis. Application to the human pathogen L. interrogans revealed mechanistic proteome changes over time involved in pathogenic progression and antibiotic defense, and new insights about the regulation of absolute protein abundances within operons.
The developed, directed proteomic approach allowed consistent detection and absolute quantification of 1680 proteins of the human pathogen L. interrogans in a single LC–MS/MS experiment.The comparison of 25 extensive, consistent and quantitative proteome maps revealed new insights about the proteome changes involved in pathogenic progression and antibiotic defense of L. interrogans, and about the regulation of protein abundances within operons.The generated time-resolved data sets are compatible with pattern analysis algorithms developed for transcriptomics, including hierarchical clustering and functional enrichment analysis of the detected profile clusters.This is the first study that describes the absolute quantitative behavior of any proteome over multiple states and represents the most comprehensive proteome abundance pattern comparison for any organism to date.
Over the last decade, mass spectrometry (MS)-based proteomics has evolved as the method of choice for system-wide proteome studies and now allows for the characterization of several thousands of proteins in a single sample. Despite these great advances, redundant monitoring of protein levels over large sample numbers in a high-throughput manner remains a challenging task. New directed MS strategies have shown to overcome some of the current limitations, thereby enabling the acquisition of consistent and system-wide data sets of proteomes with low-to-moderate complexity at high throughput.
In this study, we applied this integrated, two-stage MS strategy to investigate global proteome changes in the human pathogen L. interrogans. In the initial discovery phase, 1680 proteins (out of around 3600 gene products) could be identified (Schmidt et al, 2008) and, by focusing precious MS-sequencing time on the most dominant, specific peptides per protein, all proteins could be accurately and consistently monitored over 25 different samples within a few days of instrument time in the following scoring phase (Figure 1). Additionally, the co-analysis of heavy reference peptides enabled us to obtain absolute protein concentration estimates for all identified proteins in each perturbation (Malmström et al, 2009). The detected proteins did not show any biases against functional groups or protein classes, including membrane proteins, and span an abundance range of more than three orders of magnitude, a range that is expected to cover most of the L. interrogans proteome (Malmström et al, 2009).
To elucidate mechanistic proteome changes over time involved in pathogenic progression and antibiotic defense of L. interrogans, we generated time-resolved proteome maps of cells perturbed with serum and three different antibiotics at sublethal concentrations that are currently used to treat Leptospirosis. This yielded an information-rich proteomic data set that describes, for the first time, the absolute quantitative behavior of any proteome over multiple states, and represents the most comprehensive proteome abundance pattern comparison for any organism to date. Using this unique property of the data set, we could quantify protein components of entire pathways across several time points and subject the data sets to cluster analysis, a tool that was previously limited to the transcript level due to incomplete sampling on protein level (Figure 4). Based on these analyses, we could demonstrate that Leptospira cells adjust the cellular abundance of a certain subset of proteins and pathways as a general response to stress while other parts of the proteome respond highly specific. The cells furthermore react to individual treatments by ‘fine tuning' the abundance of certain proteins and pathways in order to cope with the specific cause of stress. Intriguingly, the most specific and significant expression changes were observed for proteins involved in motility, tissue penetration and virulence after serum treatment where we tried to simulate the host environment. While many of the detected protein changes demonstrate good agreement with available transcriptomics data, most proteins showed a poor correlation. This includes potential virulence factors, like Loa22 or OmpL1, with confirmed expression in vivo that were significantly up-regulated on the protein level, but not on the mRNA level, strengthening the importance of proteomic studies. The high resolution and coverage of the proteome data set enabled us to further investigate protein abundance changes of co-regulated genes within operons. This suggests that although most proteins within an operon respond to regulation synchronously, bacterial cells seem to have subtle means to adjust the levels of individual proteins or protein groups outside of the general trend, a phenomena that was recently also observed on the transcript level of other bacteria (Güell et al, 2009).
The method can be implemented with standard high-resolution mass spectrometers and software tools that are readily available in the majority of proteomics laboratories. It is scalable to any proteome of low-to-medium complexity and can be extended to post-translational modifications or peptide-labeling strategies for quantification. We therefore expect the approach outlined here to become a cornerstone for microbial systems biology.
Over the past decade, liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) has evolved into the main proteome discovery technology. Up to several thousand proteins can now be reliably identified from a sample and the relative abundance of the identified proteins can be determined across samples. However, the remeasurement of substantially similar proteomes, for example those generated by perturbation experiments in systems biology, at high reproducibility and throughput remains challenging. Here, we apply a directed MS strategy to detect and quantify sets of pre-determined peptides in tryptic digests of cells of the human pathogen Leptospira interrogans at 25 different states. We show that in a single LC–MS/MS experiment around 5000 peptides, covering 1680 L. interrogans proteins, can be consistently detected and their absolute expression levels estimated, revealing new insights about the proteome changes involved in pathogenic progression and antibiotic defense of L. interrogans. This is the first study that describes the absolute quantitative behavior of any proteome over multiple states, and represents the most comprehensive proteome abundance pattern comparison for any organism to date.
PMCID: PMC3159967  PMID: 21772258
absolute quantification; directed mass spectrometry; Leptospira interrogans; microbiology; proteomics
8.  Visualization and Biochemical Analyses of the Emerging Mammalian 14-3-3-Phosphoproteome* 
Molecular & Cellular Proteomics : MCP  2011;10(10):M110.005751.
Hundreds of candidate 14-3-3-binding (phospho)proteins have been reported in publications that describe one interaction at a time, as well as high-throughput 14-3-3-affinity and mass spectrometry-based studies. Here, we transcribed these data into a common format, deposited the collated data from low-throughput studies in MINT (, and compared the low- and high-throughput data in VisANT graphs that are easy to analyze and extend. Exploring the graphs prompted questions about technical and biological specificity, which were addressed experimentally, resulting in identification of phosphorylated 14-3-3-binding sites in the mitochondrial import sequence of the iron-sulfur cluster assembly enzyme (ISCU), cytoplasmic domains of the mitochondrial fission factor (MFF), and endoplasmic reticulum-tethered receptor expression-enhancing protein 4 (REEP4), RNA regulator SMAUG2, and cytoskeletal regulatory proteins, namely debrin-like protein (DBNL) and kinesin light chain (KLC) isoforms. Therefore, 14-3-3s undergo physiological interactions with proteins that are destined for diverse subcellular locations. Graphing and validating interactions underpins efforts to use 14-3-3-phosphoproteomics to identify mechanisms and biomarkers for signaling pathways in health and disease.
PMCID: PMC3205853  PMID: 21725060
9.  Spliced Leader RNAs, Mitochondrial Gene Frameshifts and Multi-Protein Phylogeny Expand Support for the Genus Perkinsus as a Unique Group of Alveolates 
PLoS ONE  2011;6(5):e19933.
The genus Perkinsus occupies a precarious phylogenetic position. To gain a better understanding of the relationship between perkinsids, dinoflagellates and other alveolates, we analyzed the nuclear-encoded spliced-leader (SL) RNA and mitochondrial genes, intron prevalence, and multi-protein phylogenies. In contrast to the canonical 22-nt SL found in dinoflagellates (DinoSL), P. marinus has a shorter (21-nt) and a longer (22-nt) SL with slightly different sequences than DinoSL. The major SL RNA transcripts range in size between 80–83 nt in P. marinus, and ∼83 nt in P. chesapeaki, significantly larger than the typical ≤56-nt dinoflagellate SL RNA. In most of the phylogenetic trees based on 41 predicted protein sequences, P. marinus branched at the base of the dinoflagellate clade that included the ancient taxa Oxyrrhis and Amoebophrya, sister to the clade of apicomplexans, and in some cases clustered with apicomplexans as a sister to the dinoflagellate clade. Of 104 Perkinsus spp. genes examined 69.2% had introns, a higher intron prevalence than in dinoflagellates. Examination of Perkinsus spp. mitochondrial cytochrome B and cytochrome C oxidase subunit I genes and their cDNAs revealed no mRNA editing, but these transcripts can only be translated when frameshifts are introduced at every AGG and CCC codon as if AGGY codes for glycine and CCCCU for proline. These results, along with the presence of the numerous uncharacterized ‘marine alveolate group I' and Perkinsus-like lineages separating perkinsids from core dinoflagellates, expand support for the affiliation of the genus Perkinsus with an independent lineage (Perkinsozoa) positioned between the phyla of Apicomplexa and Dinoflagellata.
PMCID: PMC3101222  PMID: 21629701
10.  ATAQS: A computational software tool for high throughput transition optimization and validation for selected reaction monitoring mass spectrometry 
BMC Bioinformatics  2011;12:78.
Since its inception, proteomics has essentially operated in a discovery mode with the goal of identifying and quantifying the maximal number of proteins in a sample. Increasingly, proteomic measurements are also supporting hypothesis-driven studies, in which a predetermined set of proteins is consistently detected and quantified in multiple samples. Selected reaction monitoring (SRM) is a targeted mass spectrometric technique that supports the detection and quantification of specific proteins in complex samples at high sensitivity and reproducibility. Here, we describe ATAQS, an integrated software platform that supports all stages of targeted, SRM-based proteomics experiments including target selection, transition optimization and post acquisition data analysis. This software will significantly facilitate the use of targeted proteomic techniques and contribute to the generation of highly sensitive, reproducible and complete datasets that are particularly critical for the discovery and validation of targets in hypothesis-driven studies in systems biology.
We introduce a new open source software pipeline, ATAQS (Automated and Targeted Analysis with Quantitative SRM), which consists of a number of modules that collectively support the SRM assay development workflow for targeted proteomic experiments (project management and generation of protein, peptide and transitions and the validation of peptide detection by SRM). ATAQS provides a flexible pipeline for end-users by allowing the workflow to start or end at any point of the pipeline, and for computational biologists, by enabling the easy extension of java algorithm classes for their own algorithm plug-in or connection via an external web site.
This integrated system supports all steps in a SRM-based experiment and provides a user-friendly GUI that can be run by any operating system that allows the installation of the Mozilla Firefox web browser.
Targeted proteomics via SRM is a powerful new technique that enables the reproducible and accurate identification and quantification of sets of proteins of interest. ATAQS is the first open-source software that supports all steps of the targeted proteomics workflow. ATAQS also provides software API (Application Program Interface) documentation that enables the addition of new algorithms to each of the workflow steps. The software, installation guide and sample dataset can be found in
PMCID: PMC3213215  PMID: 21414234
11.  2′-O-ribose methylation of cap2 in human: function and evolution in a horizontally mobile family 
Nucleic Acids Research  2011;39(11):4756-4768.
The 5′ cap of human messenger RNA consists of an inverted 7-methylguanosine linked to the first transcribed nucleotide by a unique 5′–5′ triphosphate bond followed by 2′-O-ribose methylation of the first and often the second transcribed nucleotides, likely serving to modify efficiency of transcript processing, translation and stability. We report the validation of a human enzyme that methylates the ribose of the second transcribed nucleotide encoded by FTSJD1, henceforth renamed HMTR2 to reflect function. Purified recombinant hMTr2 protein transfers a methyl group from S-adenosylmethionine to the 2′-O-ribose of the second nucleotide of messenger RNA and small nuclear RNA. Neither N7 methylation of the guanosine cap nor 2′-O-ribose methylation of the first transcribed nucleotide are required for hMTr2, but the presence of cap1 methylation increases hMTr2 activity. The hMTr2 protein is distributed throughout the nucleus and cytosol, in contrast to the nuclear hMTr1. The details of how and why specific transcripts undergo modification with these ribose methylations remains to be elucidated. The 2′-O-ribose RNA cap methyltransferases are present in varying combinations in most eukaryotic and many viral genomes. With the capping enzymes in hand their biological purpose can be ascertained.
PMCID: PMC3113572  PMID: 21310715
12.  ERK/p90RSK/14-3-3 signalling has an impact on expression of PEA3 Ets transcription factors via the transcriptional repressor capicúa 
Biochemical Journal  2011;433(Pt 3):515-525.
Compounds that inhibit signalling upstream of ERK (extracellular-signal-regulated kinase) are promising anticancer therapies, motivating research to define how this pathway promotes cancers. In the present study, we show that human capicúa represses mRNA expression for PEA3 (polyoma enhancer activator 3) Ets transcription factors ETV1, ETV4 and ETV5 (ETV is Ets translocation variant), and this repression is relieved by multisite controls of capicúa by ERK, p90RSK (p90 ribosomal S6 kinase) and 14-3-3 proteins. Specifically, 14-3-3 binds to p90RSK-phosphorylated Ser173 of capicúa thereby modulating DNA binding to its HMG (high-mobility group) box, whereas ERK phosphorylations prevent binding of a C-terminal NLS (nuclear localization sequence) to importin α4 (KPNA3). ETV1, ETV4 and ETV5 mRNA levels in melanoma cells are elevated by siRNA (small interfering RNA) knockdown of capicúa, and decreased by inhibiting ERK and/or expressing a form of capicúa that cannot bind to 14-3-3 proteins. Capicúa knockdown also enhances cell migration. The findings of the present study give further mechanistic insights into why ETV1 is highly expressed in certain cancers, indicate that loss of capicúa can desensitize cells to the effects of ERK pathway inhibitors, and highlight interconnections among growth factor signalling, spinocerebellar ataxias and cancers.
PMCID: PMC3025492  PMID: 21087211
cancer; capicúa; Ets translocation variant 1 (ETV1); 14-3-3 protein; spinocerebellar ataxia type 1 (SCA1); B2M, β2 microglobuluin; CRE, CIC-responsive element; DAPI, 4′,6-diamidino-2-phenylindole; DMEM, Dulbecco's modified Eagle's medium; DUX4, Double homeobox 4; ECL, enhanced chemiluminescence; EGF, epidermal growth factor; EMSA, electrophoretic mobility-shift assay; ERK, extracellular-signal-regulated kinase; ETV, Ets translocation variant; EWS, Ewing sarcoma protein; FBS, fetal bovine serum; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; GFP, green fluorescent protein; GIST, gastrointestinal stromal tumour; HA, haemagglutinin; HEK, human embryonic kidney; HMG, high-mobility group; IGF1, insulin-like growth factor 1; KPNA3, importin α4/karyopherin α3; LC, liquid chromatography; MS/MS, tandem MS; NLS, nuclear localization sequence; p90RSK, p90 ribosomal S6 kinase; PEA3, polyoma enhancer activator 3; PDK1, phosphoinositide-dependent kinase 1; PI3K, phosphoinositide 3-kinase; PKB, protein kinase B; PKC, protein kinase C; RT, reverse transcription; SCA, spinocerebellar ataxia; siRNA, small interfering RNA

Results 1-12 (12)