168 research outputs found
Fish genomes : a powerful tool to uncover new functional elements in vertebrates
This thesis spans several years of work dedicated to understanding fish genomes. In the first chapter it describes the genome of the first fish for which the entire genome was sequenced through a large-scale international project, Fugu rubripes. the pufferfish. In particular, it highlights how this fish has a genome that contains as many genes as the human genome, although it is ten times smaller. It also shows that the majority of genes that are found in the human genome can be found in this fish genome as well. In the second chapter we compared fish genomes to the human genome to find regions that have been preserved during evolution and which are therefore likely to have a function, even though they are not genes. We showed that indeed they are functional, and they help to regulate other genes. Knowing all the genes in the genome we could then interrogate how they are expressed, i.e. if they are switched __on__ or __off__ and in particular in chapter 4 we looked at how a specific gene is in charge of gradually switching off genes that are inherited from the mother in a newborn fish embryo. Finally in the last chapter since genome sequencing is now becoming much cheaper and simpler to achieve we set out to map the genome of the common carp and we discuss the best approaches and strategies to obtain a good genome sequence for this species. The common carp is a candidate model system for high-troughput screening.LEI Universiteit LeidenEuopean Commission Framework VI grant TRANSCODE (LSHG-CT-2004-511990 ) , A-STAR Singapore and Temasek Life Sciences Laboratory SingaporeAlgorithm
Human Rights and Digitalization: Threats and Challenges
Благодарности: выражаю благодарность своему научному руководителю Богатыревой О. Н. за ценные рекомендации и замечания при написании статьи.Acknowledgments: I express my gratitude to my supervisor Bogatyreva O. N. for valuable recommendations and comments when writing the article.В тезисах проанализированы основные вызовы и угрозы для прав человека, связанные с цифровизацией и развитием новых цифровых технологий. Выявлены опасности для личности в цифровой век.The thesis analyzes the main challenges and threats to human rights associated with digitalization and the development of new digital technologies. The dangers to the individual in the digital age are outlined
Virial theorem for a cloud of stars obtained from Jeans equations with the second correlation moments
A hydrodynamic model for small acoustic oscillations in a cloud of stars is
built with account of self-consistent gravitational field in equilibrium with
non-zero second correlation moment. It is assumed that the momentum flux
density tensor should include the anisotropic pressure tensor and the second
correlation moment of both longitudinal and transverse gravitational field
strength. Non-relativistic time equation for the second correlation moment of
the gravitational field strength is found from Einstein equations on the first
order post-Newtonian approximation. One longitudinal and two transverse
branches of acoustic oscillations in a homogeneous and isotropic star cloud are
found. The requirement for the velocity of transverse oscillations to be zero
gives the boundary condition of stability of the cloud. The critical radius of
the spherical cloud of stars is obtained, being precisely consistent with the
virial theorem
ParkDB: a Parkinson's disease gene expression database
Parkinson's disease (PD) is a common, adult-onset, neuro-degenerative disorder characterized by the degeneration of cardinal motor signs mainly due to the loss of dopaminergic neurons in the substantia nigra. To date, researchers still have limited understanding of the key molecular events that provoke neurodegeneration in this disease. Here, we present ParkDB, the first queryable database dedicated to gene expression in PD. ParkDB contains a complete set of re-analyzed, curated and annotated microarray datasets. This resource enables scientists to identify and compare expression signatures involved in PD and dopaminergic neuron differentiation under different biological conditions and across species. Database URL: http://www2.cancer.ucl.ac.uk/Parkinson_Db2
EFFECT OF THE SHARE OF MEAT AND OF THE SEX ON SELECTED QUANTITATIVE AND QUALITATIVE INDICES OF THE CARCASS VALUE
Comparative analysis of the testis and ovary transcriptomes in Zebrafish by combining experimental and computational tools
Studies on the zebrafish model have contributed to our understanding of several important developmental processes, especially those that can be easily studied in the embryo. However, our knowledge on late events such as gonad differentiation in the zebrafish is still limited. Here we provide an analysis on the gene sets expressed in the adult zebrafish testis and ovary in an attempt to identify genes with potential role in (zebra)fish gonad development and function. We produced 10,533 expressed sequence tags (ESTs) from zebrafish testis or ovary and downloaded an additional 23,642 gonad-derived sequences from the zebrafish EST database. We clustered these sequences together with over 13,000 kidney-derived zebrafish ESTs to study partial transcriptomes for these three organs. We searched for genes with gonad-specific expression by screening macroarrays containing at least 2600 unique cDNA inserts with testis-, ovary- and kidney-derived cDNA probes. Clones hybridizing to only one of the two gonad probes were selected, and subsequently screened with computational tools to identify 72 genes with potentially testis-specific and 97 genes with potentially ovary-specific expression, respectively. PCR-amplification confirmed gonad-specificity for 21 of the 45 clones tested (all without known function). Our study, which involves over 47,000 EST sequences and specialized cDNA arrays, is the first analysis of adult organ transcriptomes of zebrafish at such a scale. The study of genes expressed in adult zebrafish testis and ovary will provide useful information on regulation of gene expression in teleost gonads and might also contribute to our understanding of the development and differentiation of reproductive organs in vertebrates
Identification of common carp innate immune genes with whole-genome sequencing and RNA-seq data
169Computer Systems, Imagery and MediaAnimal science
HMGA1 promotes breast cancer angiogenesis supporting the stability, nuclear localization and transcriptional activity of FOXM1
Background
Breast cancer is the most common malignancy in women worldwide. Among the breast cancer subtypes, triple-negative breast cancer (TNBC) is the most aggressive and the most difficult to treat. One of the master regulators in TNBC progression is the architectural transcription factor HMGA1. This study aimed to further explore the HMGA1 molecular network to identify molecular mechanisms involved in TNBC progression.
Methods
RNA from the MDA-MB-231 cell line, silenced for HMGA1 expression, was sequenced and, with a bioinformatic analysis, molecular partners HMGA1 could cooperate with in regulating common downstream gene networks were identified. Among the putative partners, the FOXM1 transcription factor was selected. The relationship occurring between HMGA1 and FOXM1 was explored by qRT-PCR, co-immunoprecipitation and protein stability assays. Subsequently, the transcriptional activity of HMGA1 and FOXM1 was analysed by luciferase assay on the VEGFA promoter. The impact on angiogenesis was assessed in vitro, evaluating the tube formation ability of endothelial cells exposed to the conditioned medium of MDA-MB-231 cells silenced for HMGA1 and FOXM1 and in vivo injecting MDA-MB-231 cells, silenced for the two factors, in zebrafish larvae.
Results
Here, we discover FOXM1 as a novel molecular partner of HMGA1 in regulating a gene network implicated in several breast cancer hallmarks. HMGA1 forms a complex with FOXM1 and stabilizes it in the nucleus, increasing its transcriptional activity on common target genes, among them, VEGFA, the main inducer of angiogenesis. Furthermore, we demonstrate that HMGA1 and FOXM1 synergistically drive breast cancer cells to promote tumor angiogenesis both in vitro in endothelial cells and in vivo in a zebrafish xenograft model. Moreover, using a dataset of breast cancer patients we show that the co-expression of HMGA1, FOXM1 and VEGFA is a negative prognostic factor of distant metastasis-free survival and relapse-free survival.
Conclusions
This study reveals FOXM1 as a crucial interactor of HMGA1 and proves that their cooperative action supports breast cancer aggressiveness, by promoting tumor angiogenesis. Therefore, the possibility to target HMGA1/FOXM1 in combination should represent an attractive therapeutic option to counteract breast cancer angiogenesis
Chemically induced protein cage assembly with programmable opening and cargo release
Engineered protein cages are promising tools that can be customized for applications in medicine and nanotechnology. A major challenge is developing a straightforward strategy for endowing cages with bespoke, inducible disassembly. Such cages would allow release of encapsulated cargoes at desired timing and location. Here, we achieve such programmable disassembly using protein cages, in which the subunits are held together by different molecular cross-linkers. This modular system enables cage disassembly to be controlled in a condition-dependent manner. Structural details of the resulting cages were determined using cryo–electron microscopy, which allowed observation of bridging cross-linkers at intended positions. Triggered disassembly was demonstrated by high-speed atomic force microscopy and subsequent cargo release using an encapsulated Förster resonance energy transfer pair whose signal depends on the quaternary structure of the cage
The Bioperl toolkit: Perl modules for the life sciences
The Bioperl project is an international open-source collaboration of biologists, bioinformaticians, and computer scientists that has evolved over the past 7 yr into the most comprehensive library of Perl modules available for managing and manipulating life-science information. Bioperl provides an easy-to-use, stable, and consistent programming interface for bioinformatics application programmers. The Bioperl modules have been successfully and repeatedly used to reduce otherwise complex tasks to only a few lines of code. The Bioperl object model has been proven to be flexible enough to support enterprise-level applications such as EnsEMBL, while maintaining an easy learning curve for novice Perl programmers. Bioperl is capable of executing analyses and processing results from programs such as BLAST, ClustalW, or the EMBOSS suite. Interoperation with modules written in Python and Java is supported through the evolving BioCORBA bridge. Bioperl provides access to data stores such as GenBank and SwissProt via a flexible series of sequence input/output modules, and to the emerging common sequence data storage format of the Open Bioinformatics Database Access project. This study describes the overall architecture of the toolkit, the problem domains that it addresses, and gives specific examples of how the toolkit can be used to solve common life-sciences problems. We conclude with a discussion of how the open-source nature of the project has contributed to the development effort
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