Search results for "script"
showing 10 items of 5143 documents
On the contribution of molecular topology to drug design and discovery.
2010
Abstract The role of molecular topology (MT) in the design and selection of new drugs is discussed. After an overview of the different in silico molecular design current technologies, the QSAR analysis is dealt in detail with particular emphasis in the use of topological indices as molecular descriptors. The results of the application of MT in drug design and discovery are described and finally a possible explanation is given about some of the key reasons explaining it's the extraordinary performance.
Computational Methods in Developing Quantitative Structure-Activity Relationships (QSAR): A Review
2006
Virtual filtering and screening of combinatorial libraries have recently gained attention as methods complementing the high-throughput screening and combinatorial chemistry. These chemoinformatic techniques rely heavily on quantitative structure-activity relationship (QSAR) analysis, a field with established methodology and successful history. In this review, we discuss the computational methods for building QSAR models. We start with outlining their usefulness in high-throughput screening and identifying the general scheme of a QSAR model. Following, we focus on the methodologies in constructing three main components of QSAR model, namely the methods for describing the molecular structure …
RNA nucleotide methylation
2011
Methylation of RNA occurs at a variety of atoms, nucleotides, sequences and tertiary structures. Strongly related to other posttranscriptional modifications, methylation of different RNA species includes tRNA, rRNA, mRNA, tmRNA, snRNA, snoRNA, miRNA, and viral RNA. Different catalytic strategies are employed for RNA methylation by a variety of RNA-methyltransferases which fall into four superfamilies. This review outlines the different functions of methyl groups in RNA, including biophysical, biochemical and metabolic stabilization of RNA, quality control, resistance to antibiotics, mRNA reading frame maintenance, deciphering of normal and altered genetic code, selenocysteine incorporation,…
Structural Characterization of Set1 RNA Recognition Motifs and their Role in Histone H3 Lysine 4 Methylation
2006
Departament de Bioquimica iBiologia Molecular, Universitatde Valencia, C/Dr Moliner 50,46100, Burjassot, SpainThe yeast Set1 histone H3 lysine 4 (H3K4) methyltransferase contains, inaddition to its catalytic SET domain, a conserved RNA recognition motif(RRM1). We present here the crystal structure and the secondary structureassignment in solution of the Set1 RRM1. Although RRM1 has the expectedβαββαβ RRM-fold, it lacks the typical RNA-binding features of thesemodules. RRM1 is not able to bind RNA by itself in vitro, but a constructcombining RRM1 with a newly identified downstream RRM2 specificallybinds RNA. Invivo,H3K4 methylation isnot affectedbyapoint mutation inRRM2 that preserves Set1 s…
Antibody inhibition of the transcriptase activity of the rotavirus DLP: a structural view.
2001
On entering the host cell the rotavirus virion loses its outer shell to become a double-layered particle (DLP). The DLP then transcribes the 11 segments of its dsRNA genome using its own transcriptase complex, and the mature mRNA emerges along the 5-fold axis. In order to better understand the transcription mechanism and the role of VP6 in transcription we have studied three monoclonal antibodies against VP6: RV-238 which inhibits the transcriptase activity of the DLP; and RV-133 and RV-138 which have no effect on transcription. The structures obtained by cryo-electron microscopy of the DLP/Fab complexes and by X-ray crystallography of the VP6 trimer and the VP6/Fab-238 complex have been co…
Homology modeling using simulated annealing of restrained molecular dynamics and conformational search calculations with CONGEN: application in predi…
1997
We have developed an automatic approach for homology modeling using restrained molecular dynamics and simulated annealing procedures, together with conformational search algorithms available in the molecular mechanics program CONGEN (Bruccoleri RE, Karplus M, 1987, Biopolymers 26:137-168). The accuracy of the method is validated by "predicting" structures of two homeodomain proteins with known three-dimensional structures, and then applied to predict the three-dimensional structure of the homeodomain of the murine Msx-1 transcription factor. Regions of the unknown protein structure that are highly homologous to the known template structure are constrained by "homology distance constraints,"…
Structure-based analyses of Salmonella RcsB variants unravel new features of the Rcs regulon
2021
18 páginas, 7 figuras, 2 tablas
Structure-Activity Relationships and X-ray Structures Describing the Selectivity of Aminopyrazole Inhibitors for c-Jun N-terminal Kinase 3 (JNK3) ove…
2009
c-Jun N-terminal kinase 3alpha1 (JNK3alpha1) is a mitogen-activated protein kinase family member expressed primarily in the brain that phosphorylates protein transcription factors, including c-Jun and activating transcription factor-2 (ATF-2) upon activation by a variety of stress-based stimuli. In this study, we set out to design JNK3-selective inhibitors that had >1000-fold selectivity over p38, another closely related mitogen-activated protein kinase family member. To do this we employed traditional medicinal chemistry principles coupled with structure-based drug design. Inhibitors from the aminopyrazole class, such as SR-3576, were found to be very potent JNK3 inhibitors (IC(50) = 7 nm)…
Characterization of aCandida albicansgene encoding a putative transcriptional factor required for cell wall integrity
2003
After screening a Candida albicans genome database the product of an open reading frame (ORF) (CA2880) with 49% homology to the product of Saccharomyces cerevisiae YPL133c, a putative transcriptional factor, was identified. The disruption of the C. albicans gene leads to a major sensitivity to calcofluor white and Congo red, a minor sensitivity to sodium dodecyl sulfate, a major resistance to zymolyase, and an alteration of the chemical composition of the cell wall. For these reasons we called it CaCWT1 (for C. albicans cell wall transcription factor). CaCwt1p contains a putative Zn(II) Cys(6) DNA binding domain characteristic of some transcriptional factors and a PAS domain. The CaCWT1 gen…
Structural and Functional Basis for Understanding the Biological Significance of P2X7 Receptor
2020
The P2X7 receptor (P2X7R) possesses a unique structure associated to an as yet not fully understood mechanism of action that facilitates cell permeability to large ionic molecules through the receptor itself and/or nearby membrane proteins. High extracellular adenosine triphosphate (ATP) levels—inexistent in physiological conditions—are required for the receptor to be triggered and contribute to its role in cell damage signaling. The inconsistent data on its activation pathways and the few studies performed in natively expressed human P2X7R have led us to review the structure, activation pathways, and specific cellular location of P2X7R in order to analyze its biological relevance. The ATP-…