Archive for December, 2009
Reconstructing nonlinear dynamic models of gene regulation using stochastic sampling
Posted by Waleed Ghalwash in MedWorm.com on December 29th, 2009
Conclusions:
Our approach combines dynamic modeling using differential equations with a stochastic learning framework, thus bridging the gap between biophysical modeling and stochastic inference approaches. Results show that the method can reap the advantages of both worlds, and allows the reconstruction of biophysically accurate dynamic models from noisy data. In addition, the stochastic learning framework used permits the computation of probability distributions over models and model parameters, which holds interesting prospects for experimental design purposes. (Source: BMC Bioinformatics – Latest articles)
Identification and Characterization of a Novel Deoxyhypusine Synthase in Leishmania donovani [Genomics, Proteomics, and Bioinformatics]
Posted by Waleed Ghalwash in MedWorm.com on December 29th, 2009
Deoxyhypusine synthase, an NAD+-dependent enzyme, catalyzes the first step in the post-translational synthesis of an unusual amino acid, hypusine (N-(4-amino-2-hydroxybutyl)lysine), in the eukaryotic initiation factor 5A precursor protein. Two putative deoxyhypusine synthase (DHS) sequences have been identified in the Leishmania donovani genome, which are present on chromosomes 20: DHSL20 (DHS-like gene from chromosome 20) and DHS34 (DHS from chromosome 34). Although both sequences exhibit an overall conservation of key residues, DHSL20 protein lacks a critical lysine residue, and the recombinant protein showed no DHS activity in vitro. However, DHS34 contains the critical lysine residue, and the recombinant DHS34 effectively catalyzed deoxyhypusine synthesis. Furthermore, in vivo labeling…
Regulation of Epidermal Growth Factor Receptor Trafficking by Lysine Deacetylase HDAC6.
Posted by Waleed Ghalwash in MedWorm.com on December 29th, 2009
This study illustrates the complexity of the EGFR-associated interactome and identifies protein acetylation as a previously unknown regulator of receptor endocytosis and degradation.
PMID: 20029029 [PubMed - in process] (Source: Science Signaling)
A Quick Guide for Developing Effective Bioinformatics Programming Skills
Posted by Waleed Ghalwash in MedWorm.com on December 29th, 2009
(Source: PLoS Computational Biology)
Data mining of enzymes using specific peptides
Posted by Waleed Ghalwash in MedWorm.com on December 29th, 2009
Conclusions:
Employing SPs for predicting enzymatic activity of proteins works well once one utilizes coverage-length criteria. In our analysis, L[greater than or equal to]7 has led to highly accurate results. (Source: BMC Bioinformatics – Latest articles)
LipocalinPred: a SVM-based method for prediction of lipocalins
Posted by Waleed Ghalwash in MedWorm.com on December 29th, 2009
Conclusion:
The method offers a promising approach as a lipocalin prediction tool, complementing PROSITE, Pfam and homology modelling methods. (Source: BMC Bioinformatics – Latest articles)div id=medwormpbiMedWorm Message:/i/b Get the very latest Swine Flu news via the MedWorm ba href=http://www.medworm.com/rss/search.php?qu=%2Bswine+%2B%28influenza+flu%29t=Swine+Fluf=infectiousdiseasesr=Anyo=d target =_selfSwine Flu RSS news feed/a/b – updated hourly from thousands of authoritative health and news sources./p/div
Human genetic variation recognizes functional elements in non-coding sequence [RESEARCH]
Posted by Waleed Ghalwash in MedWorm.com on December 29th, 2009
Non-coding DNA, particularly intronic DNA, harbors important functional elements that affect gene expression and RNA splicing. Yet, it is unclear which specific non-coding sites are essential for gene function and regulation. To identify functional elements in non-coding DNA, we characterized genetic variation within introns using ethnically diverse human polymorphism data from three public databases, PMT, NIEHS, and Seattle SNPs. We demonstrate that positions within introns corresponding to known functional elements involved in pre-mRNA splicing, including the branch site, splice sites, and polypyrimidine tract show reduced levels of genetic variation. Additionally, we observed regions of reduced genetic variation that are candidates for distance dependent localization sites of functional…
Simulation of P systems with active membranes on CUDA
Posted by Waleed Ghalwash in Oxford journals on December 29th, 2009
P systems or Membrane Systems provide a high-level computational modelling framework that combines the structure and dynamic aspects of biological systems in a relevant and understandable way. They are inherently parallel and non-deterministic computing devices. In this article, we discuss the motivation, design principles and key of the implementation of a simulator for the class of recognizer P systems with active membranes running on a (GPU). We compare our parallel simulator for GPUs to the simulator developed for a single central processing unit (CPU), showing that GPUs are better suited than CPUs to simulate P systems due to their highly parallel nature.
Molecular networks for the study of TCM Pharmacology
Posted by Waleed Ghalwash in Oxford journals on December 29th, 2009
To target complex, multi-factorial diseases more effectively, there has been an emerging trend of multi-target drug development based on network biology, as well as an increasing interest in traditional Chinese medicine (TCM) that applies a more holistic treatment to diseases. Thousands of years’ clinic practices in TCM have accumulated a considerable number of formulae that exhibit reliable in vivo efficacy and safety. However, the molecular mechanisms responsible for their therapeutic effectiveness are still unclear. The development of network-based systems biology has provided considerable support for the understanding of the holistic, complementary and synergic essence of TCM in the context of molecular networks. This review introduces available sources and methods that could be utilized for the network-based study of TCM pharmacology, proposes a workflow for network-based TCM pharmacology study, and presents two case studies on applying these sources and methods to understand the mode of action of TCM recipes.
MultiTest V.1.2, a program to binomially combine independent tests and performance comparison with other related methods on proportional data
Posted by Waleed Ghalwash in MedWorm.com on December 24th, 2009
Conclusion:
Based on our results and those discussed in the literature we conclude that the generalised binomial and Stouffer’s Z procedures should be preferred and Z when the number of tests is very small. The more conservative SGM might still be appropriate for meta-analyses when a strong publication bias in favour of significant results is expected to inflate type 2 error. (Source: BMC Bioinformatics – Latest articles)
