Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Chem Inf Model ; 60(3): 1481-1493, 2020 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-31909998

RESUMEN

This article introduces Web-ARM, a specialized tool, online available, designed to build quantum mechanical/molecular mechanical models of rhodopsins, a widely spread family of light-responsive proteins. Web-ARM allows the rapidly building of models of rhodopsins with a documented quality and the prediction of trends in UV-vis absorption maximum wavelengths, based on their excitation energies computed at the CASPT2//CASSCF/Amber level of theory. Web-ARM builds upon the recently reported, python-based a-ARM protocol [J. Chem. Theory Comput., 2019, 15, 3134-3152] and, as such, necessitates only a crystallographic structure or a comparative model in PDB format and a very basic knowledge of the studied rhodopsin system. The user-friendly web interface uses such input to generate congruous, gas-phase models of rhodopsins and, if requested, their mutants. We present two possible applications of Web-ARM, which showcase how the interface can be employed to assist both research and educational activities in fields at the interface between chemistry and biology. The first application shows how, through Web-ARM, research projects (e.g., rhodopsin and rhodopsin mutant screening) can be carried out in significantly less time with respect to using the required computational photochemistry tools via a command line. The second application documents the use of Web-ARM in a real-life educational/training activity, through a hands-on experience illustrating the concepts of rhodopsin color tuning.


Asunto(s)
Teoría Cuántica , Rodopsina , Internet , Modelos Moleculares
2.
Phys Chem Chem Phys ; 22(39): 22302-22313, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33006338

RESUMEN

We report bond formation induced by an ultrashort UV pulse. The photochemical process is described by quantum dynamics as coherent electronic and nuclear motions during the ultrashort pulse induced ring closure of norbornadiene to quadricyclane. Norbornadiene consists of two ethylene moieties connected by a rigid (CH2)3 bridge. Upon photoexcitation, two new sigma bonds are formed, resulting in the closure of a four-atom ring. As a medium-sized polyatomic molecule, norbornadiene exhibits a high density of strongly coupled electronic states from about 6 eV above the ground state. We report on inducing the formation of the new bonds using a short femtosecond UV pulse to pump a non-equilibrium electronic density in the open form that evolves towards the closed ring form. As the coherent electronic-nuclear coupled dynamics unfold, the excited states change character through non-adiabatic interactions and become valence states for the two new C-C bonds of quadricyclane. Our three-dimensional fully quantum dynamical grid simulations during the first 200 fs show that short UV pulses of different polarization initiate markedly different initial non-equilibrium electronic densities that follow different dynamical paths to the S0/S1 conical intersection. They lead to different initial relative yields of quadricyclane, thereby opening the way to controlling bond-making with attopulses.

3.
J Chem Phys ; 152(21): 214117, 2020 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-32505150

RESUMEN

MOLCAS/OpenMolcas is an ab initio electronic structure program providing a large set of computational methods from Hartree-Fock and density functional theory to various implementations of multiconfigurational theory. This article provides a comprehensive overview of the main features of the code, specifically reviewing the use of the code in previously reported chemical applications as well as more recent applications including the calculation of magnetic properties from optimized density matrix renormalization group wave functions.

4.
J Am Chem Soc ; 141(1): 262-271, 2019 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-30532962

RESUMEN

The engineering of microbial rhodopsins with enhanced fluorescence is of great importance in the expanding field of optogenetics. Here we report the discovery of two mutants (W76S/Y179F and L83Q) of a sensory rhodopsin from the cyanobacterium Anabaena PCC7120 with opposite fluorescence behavior. In fact, while W76S/Y179F displays, with respect to the wild-type protein, a nearly 10-fold increase in red-light emission, the second is not emissive. Thus, the W76S/Y179F, L83Q pair offers an unprecedented opportunity for the investigation of fluorescence enhancement in microbial rhodopsins, which is pursued by combining transient absorption spectroscopy and multiconfigurational quantum chemistry. The results of such an investigation point to an isomerization-blocking electronic effect as the direct cause of instantaneous (subpicosecond) fluorescence enhancement.


Asunto(s)
Anabaena/metabolismo , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Ingeniería de Proteínas , Rodopsinas Microbianas/química , Rodopsinas Microbianas/metabolismo , Transporte de Electrón , Modelos Moleculares , Proteínas Mutantes/genética , Conformación Proteica , Rodopsinas Microbianas/genética , Espectrometría de Fluorescencia
5.
Angew Chem Int Ed Engl ; 56(14): 3842-3846, 2017 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-28251753

RESUMEN

The quantum yield of a photochemical reaction is one of the most fundamental quantities in photochemistry, as it measures the efficiency of the transduction of light energy into chemical energy. Nature has evolved photoreceptors in which the reactivity of a chromophore is enhanced by its molecular environment to achieve high quantum yields. The retinal chromophore sterically constrained inside rhodopsin proteins represents an outstanding example of such a control. In a more general framework, mechanical forces acting on a molecular system can strongly modify its reactivity. Herein, we show that the exertion of tensile forces on a simplified retinal chromophore model provokes a substantial and regular increase in the trans-to-cis photoisomerization quantum yield in a counterintuitive way, as these extension forces facilitate the formation of the more compressed cis photoisomer. A rationale for the mechanochemical effect on this photoisomerization mechanism is also proposed.


Asunto(s)
Modelos Químicos , Teoría Cuántica , Retinaldehído/química , Estructura Molecular , Procesos Fotoquímicos , Rodopsina/química , Estereoisomerismo
6.
J Comput Chem ; 37(5): 506-41, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26561362

RESUMEN

In this report, we summarize and describe the recent unique updates and additions to the Molcas quantum chemistry program suite as contained in release version 8. These updates include natural and spin orbitals for studies of magnetic properties, local and linear scaling methods for the Douglas-Kroll-Hess transformation, the generalized active space concept in MCSCF methods, a combination of multiconfigurational wave functions with density functional theory in the MC-PDFT method, additional methods for computation of magnetic properties, methods for diabatization, analytical gradients of state average complete active space SCF in association with density fitting, methods for constrained fragment optimization, large-scale parallel multireference configuration interaction including analytic gradients via the interface to the Columbus package, and approximations of the CASPT2 method to be used for computations of large systems. In addition, the report includes the description of a computational machinery for nonlinear optical spectroscopy through an interface to the QM/MM package Cobramm. Further, a module to run molecular dynamics simulations is added, two surface hopping algorithms are included to enable nonadiabatic calculations, and the DQ method for diabatization is added. Finally, we report on the subject of improvements with respects to alternative file options and parallelization.


Asunto(s)
Algoritmos , Electrones , Compuestos Macrocíclicos/química , Timidina/química , Simulación de Dinámica Molecular , Teoría Cuántica , Programas Informáticos , Termodinámica
7.
Genet Sel Evol ; 48(1): 58, 2016 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-27521154

RESUMEN

BACKGROUND: Cattle include a large number of breeds that are characterized by marked phenotypic differences and thus constitute a valuable model to study genome evolution in response to processes such as selection and domestication. Detection of "signatures of selection" is a useful approach to study the evolutionary pressures experienced throughout history. In the present study, signatures of selection were investigated in five cattle breeds farmed in Italy using a multivariate approach. METHODS: A total of 4094 bulls from five breeds with different production aptitudes (two dairy breeds: Italian Holstein and Italian Brown Swiss; two beef breeds: Piemontese and Marchigiana; and one dual purpose breed: Italian Simmental) were genotyped using the Illumina BovineSNP50 v.1 beadchip. Canonical discriminant analysis was carried out on the matrix of single nucleotide polymorphisms (SNP) genotyping data, separately for each chromosome. Scores for each canonical variable were calculated and then plotted in the canonical space to quantify the distance between breeds. SNPs for which the correlation with the canonical variable was in the 99th percentile for a specific chromosome were considered to be significantly associated with that variable. Results were compared with those obtained using an FST-based approach. RESULTS: Based on the results of the canonical discriminant analysis, a large number of signatures of selection were detected, among which several had strong signals in genomic regions that harbour genes known to have an impact on production and morphological bovine traits, including MSTN, LCT, GHR, SCD, NCAPG, KIT, and ASIP. Moreover, new putative candidate genes were identified, such as GCK, B3GALNT1, MGAT1, GALNTL1, PRNP, and PRND. Similar results were obtained with the FST-based approach. CONCLUSIONS: The use of canonical discriminant analysis on 50 K SNP genotypes allowed the extraction of new variables that maximize the separation between breeds. This approach is quite straightforward, it can compare more than two groups simultaneously, and relative distances between breeds can be visualized. The genes that were highlighted in the canonical discriminant analysis were in concordance with those obtained using the FST index.


Asunto(s)
Cruzamiento , Bovinos/genética , Análisis Discriminante , Genómica/métodos , Selección Genética , Animales , Frecuencia de los Genes , Genotipo , Italia , Masculino , Polimorfismo de Nucleótido Simple
8.
Genet Sel Evol ; 47: 52, 2015 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-26100250

RESUMEN

BACKGROUND: Domestication and selection are processes that alter the pattern of within- and between-population genetic variability. They can be investigated at the genomic level by tracing the so-called selection signatures. Recently, sequence polymorphisms at the genome-wide level have been investigated in a wide range of animals. A common approach to detect selection signatures is to compare breeds that have been selected for different breeding goals (i.e. dairy and beef cattle). However, genetic variations in different breeds with similar production aptitudes and similar phenotypes can be related to differences in their selection history. METHODS: In this study, we investigated selection signatures between two Italian beef cattle breeds, Piemontese and Marchigiana, using genotyping data that was obtained with the Illumina BovineSNP50 BeadChip. The comparison was based on the fixation index (Fst), combined with a locally weighted scatterplot smoothing (LOWESS) regression and a control chart approach. In addition, analyses of Fst were carried out to confirm candidate genes. In particular, data were processed using the varLD method, which compares the regional variation of linkage disequilibrium between populations. RESULTS: Genome scans confirmed the presence of selective sweeps in the genomic regions that harbour candidate genes that are known to affect productive traits in cattle such as DGAT1, ABCG2, CAPN3, MSTN and FTO. In addition, several new putative candidate genes (for example ALAS1, ABCB8, ACADS and SOD1) were detected. CONCLUSIONS: This study provided evidence on the different selection histories of two cattle breeds and the usefulness of genomic scans to detect selective sweeps even in cattle breeds that are bred for similar production aptitudes.


Asunto(s)
Bovinos/genética , Selección Genética , Selección Artificial/genética , Animales , Bases de Datos Genéticas , Desequilibrio de Ligamiento , Fenotipo , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo
9.
Genet Sel Evol ; 47: 25, 2015 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-25888030

RESUMEN

BACKGROUND: A number of methods are available to scan a genome for selection signatures by evaluating patterns of diversity within and between breeds. Among these, "extended haplotype homozygosity" (EHH) is a reliable approach to detect genome regions under recent selective pressure. The objective of this study was to use this approach to identify regions that are under recent positive selection and shared by the most representative Italian dairy and beef cattle breeds. RESULTS: A total of 3220 animals from Italian Holstein (2179), Italian Brown (775), Simmental (493), Marchigiana (485) and Piedmontese (379) breeds were genotyped with the Illumina BovineSNP50 BeadChip v.1. After standard quality control procedures, genotypes were phased and core haplotypes were identified. The decay of linkage disequilibrium (LD) for each core haplotype was assessed by measuring the EHH. Since accurate estimates of local recombination rates were not available, relative EHH (rEHH) was calculated for each core haplotype. Genomic regions that carry frequent core haplotypes and with significant rEHH values were considered as candidates for recent positive selection. Candidate regions were aligned across to identify signals shared by dairy or beef cattle breeds. Overall, 82 and 87 common regions were detected among dairy and beef cattle breeds, respectively. Bioinformatic analysis identified 244 and 232 genes in these common genomic regions. Gene annotation and pathway analysis showed that these genes are involved in molecular functions that are biologically related to milk or meat production. CONCLUSIONS: Our results suggest that a multi-breed approach can lead to the identification of genomic signatures in breeds of cattle that are selected for the same production goal and thus to the localisation of genomic regions of interest in dairy and beef production.


Asunto(s)
Bovinos/genética , Haplotipos , Selección Genética , Animales , Cruzamiento , Industria Lechera , Genómica , Homocigoto , Masculino , Carne , Anotación de Secuencia Molecular
10.
Genet Sel Evol ; 47: 62, 2015 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-26239391

RESUMEN

BACKGROUND: Among the European countries, Italy counts the largest number of local goat breeds. Thanks to the recent availability of a medium-density SNP (single nucleotide polymorphism) chip for goat, the genetic diversity of Italian goat populations was characterized by genotyping samples from 14 Italian goat breeds that originate from different geographical areas with more than 50 000 SNPs evenly distributed on the genome. RESULTS: Analysis of the genotyping data revealed high levels of genetic polymorphism and an underlying North-south geographic pattern of genetic diversity that was highlighted by both the first dimension of the multi-dimensional scaling plot and the Neighbour network reconstruction. We observed a moderate and weak population structure in Northern and Central-Southern breeds, respectively, with pairwise FST values between breeds ranging from 0.013 to 0.164 and 7.49 % of the total variance assigned to the between-breed level. Only 2.11 % of the variance explained the clustering of breeds into geographical groups (Northern, Central and Southern Italy and Islands). CONCLUSIONS: Our results indicate that the present-day genetic diversity of Italian goat populations was shaped by the combined effects of drift, presence or lack of gene flow and, to some extent, by the consequences of traditional management systems and recent demographic history. Our findings may constitute the starting point for the development of marker-assisted approaches, to better address future breeding and management policies in a species that is particularly relevant for the medium- and long-term sustainability of marginal regions.


Asunto(s)
Cabras/clasificación , Cabras/genética , Polimorfismo de Nucleótido Simple , Animales , Flujo Génico , Flujo Genético , Genotipo , Endogamia , Italia , Filogeografía
11.
Anim Genet ; 46(2): 110-21, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25530322

RESUMEN

Increased inbreeding is an inevitable consequence of selection in livestock populations. The analysis of high-density single nucleotide polymorphisms (SNPs) facilitates the identification of long and uninterrupted runs of homozygosity (ROH) that can be used to identify chromosomal regions that are identical by descent. In this work, the distribution of ROH of different lengths in five Italian cattle breeds is described. A total of 4095 bulls from five cattle breeds (2093 Italian Holstein, 749 Italian Brown, 364 Piedmontese, 410 Marchigiana and 479 Italian Simmental) were genotyped at 54K SNP loci. ROH were identified and used to estimate molecular inbreeding coefficients (FROH ), which were compared with inbreeding coefficients estimated from pedigree information (FPED ) and using the genomic relationship matrix (FGRM ). The average number of ROH per animal ranged from 54 ± 7.2 in Piedmontese to 94.6 ± 11.6 in Italian Brown. The highest number of short ROH (related to ancient consanguinity) was found in Piedmontese, followed by Simmental. The Italian Brown and Holstein had a higher proportion of longer ROH distributed across the whole genome, revealing recent inbreeding. The FPED were moderately correlated with FROH > 1 Mb (0.662, 0.700 and 0.669 in Italian Brown, Italian Holstein and Italian Simmental respectively) but poorly correlated with FGRM (0.134, 0.128 and 0.448 for Italian Brown, Italian Holstein and Italian Simmental respectively). The inclusion of ROH > 8 Mb in the inbreeding calculation improved the correlation of FROH with FPED and FGRM . ROH are a direct measure of autozygosity at the DNA level and can overcome approximations and errors resulting from incomplete pedigree data. In populations with high linkage disequilibrium (LD) and recent inbreeding (e.g. Italian Holstein and Italian Brown), a medium-density marker panel, such as the one used here, may provide a good estimate of inbreeding. However, in populations with low LD and ancient inbreeding, marker density would have to be increased to identify short ROH that are identical by descent more precisely.


Asunto(s)
Bovinos/genética , Endogamia , Animales , Genotipo , Homocigoto , Italia , Modelos Lineales , Desequilibrio de Ligamiento , Masculino , Linaje , Polimorfismo de Nucleótido Simple
12.
BMC Genet ; 15: 119, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25377122

RESUMEN

BACKGROUND: Success of meat production and selection for improvement of meat quality is among the primary aims in animal production. Meat quality traits are economically important in swine; however, the underlying genetic nature is very complex. Therefore, an improved pork production strongly depends on identifying and studying how genetic variations contribute to modulate gene expression. Promoters are key regions in gene modulation as they harbour several binding motifs to transcription regulatory factors. Therefore, polymorphisms in these regions are likely to deeply affect RNA levels and consequently protein synthesis. In this study, we report the identification of single nucleotide polymorphisms (SNPs) in promoter regions of candidate genes involved in development, cellular differentiation and muscle growth in Sus scrofa. We identified SNPs in the promoter regions of genes belonging to the Myogenic Regulatory Factors (MRF) gene family (the Myogenic Differentiation gene, MYOD1) and to Growth and Differentiation Factors (GDF) gene family (Myostatin gene, MSTN, GDF8), in Casertana and Large White breeds. The purpose of this study was to investigate if polymorphisms in the promoters could affect the transcriptional activity of these genes. With this aim, we evaluated in vitro the functional activity of the luciferase reporter gene luc2 activity, driven by two constructs carrying different promoter haplotypes. RESULTS: We tested the effects of the G302A (U12574) transition on the promoter efficiency in MYOD1 gene. We ascertained a difference in transcription efficiency for the two variants. A stronger activity of the A-carrying construct is more evident in C2C12. The luciferase expression driven by the MYOD1-A allelic variant displayed a 3.8-fold increased transcriptional activity. We investigated the activity of two haplotype variants (AY527152) in the promoter of GDF8 gene. The haploptype-1 (A435-A447-A879) up-regulated the expression of the reporter gene by a two-fold increase, and hence presumably of the GDF8 gene, in both CHO and C2C12 cultured cells. CONCLUSIONS: In vitro the MYOD1-A allelic variant could up-regulate the expression of MYOD1 gene. Additionally, we could assess a different response of in vitro gene expression according to cell type used to transfect constructs, suggesting that MyoD activation is regulated by mechanisms that are specific of myoblasts.


Asunto(s)
Desarrollo de Músculos , Proteína MioD/genética , Miostatina/genética , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Animales , Células CHO , Cricetinae , Cricetulus , Calidad de los Alimentos , Frecuencia de los Genes , Carne , Ratones , Músculo Esquelético/crecimiento & desarrollo , Músculo Esquelético/metabolismo , Proteína MioD/metabolismo , Miostatina/metabolismo , Fenotipo , Análisis de Secuencia de ADN , Sus scrofa/genética , Sus scrofa/crecimiento & desarrollo , Transcripción Genética , Activación Transcripcional
13.
Mol Biol Rep ; 41(2): 957-65, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24442315

RESUMEN

In this study we used a medium density panel of SNP markers to perform population genetic analysis in five Italian cattle breeds. The BovineSNP50 BeadChip was used to genotype a total of 2,935 bulls of Piedmontese, Marchigiana, Italian Holstein, Italian Brown and Italian Pezzata Rossa breeds. To determine a genome-wide pattern of positive selection we mapped the F st values against genome location. The highest F st peaks were obtained on BTA6 and BTA13 where some candidate genes are located. We identified selection signatures peculiar of each breed which suggest selection for genes involved in milk or meat traits. The genetic structure was investigated by using a multidimensional scaling of the genetic distance matrix and a Bayesian approach implemented in the STRUCTURE software. The genotyping data showed a clear partitioning of the cattle genetic diversity into distinct breeds if a number of clusters equal to the number of populations were given. Assuming a lower number of clusters beef breeds group together. Both methods showed all five breeds separated in well defined clusters and the Bayesian approach assigned individuals to the breed of origin. The work is of interest not only because it enriches the knowledge on the process of evolution but also because the results generated could have implications for selective breeding programs.


Asunto(s)
Cruzamiento , Variación Genética , Polimorfismo de Nucleótido Simple/genética , Selección Genética , Animales , Teorema de Bayes , Bovinos , Genética de Población , Genoma , Genotipo , Italia
14.
BMC Genomics ; 14: 124, 2013 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-23442185

RESUMEN

BACKGROUND: Copy number variations (CNVs) represent a significant source of genomic structural variation. Their length ranges from approximately one hundred to millions of base pair. Genome-wide screenings have clarified that CNVs are a ubiquitous phenomenon affecting essentially the whole genome. Although Bos taurus is one of the most important domestic animal species worldwide and one of the most studied ruminant models for metabolism, reproduction, and disease, relatively few studies have investigated CNVs in cattle and little is known about how CNVs contribute to normal phenotypic variation and to disease susceptibility in this species, compared to humans and other model organisms. RESULTS: Here we characterize and compare CNV profiles in 2654 animals from five dairy and beef Bos taurus breeds, using the Illumina BovineSNP50 genotyping array (54001 SNP probes). In this study we applied the two most commonly used algorithms for CNV discovery (QuantiSNP and PennCNV) and identified 4830 unique candidate CNVs belonging to 326 regions. These regions overlap with 5789 known genes, 76.7% of which are significantly co-localized with segmental duplications (SD). CONCLUSIONS: This large scale screening significantly contributes to the enrichment of the Bos taurus CNV map, demonstrates the ubiquity, great diversity and complexity of this type of genomic variation and sets the basis for testing the influence of CNVs on Bos taurus complex functional and production traits.


Asunto(s)
Variaciones en el Número de Copia de ADN , Genoma , Algoritmos , Animales , Bovinos , Hibridación Genómica Comparativa , Biología Computacional , Genotipo , Polimorfismo de Nucleótido Simple , Duplicaciones Segmentarias en el Genoma , Análisis de Secuencia de ADN
15.
BMC Vet Res ; 9: 122, 2013 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-23782433

RESUMEN

BACKGROUND: Bovine Spastic Paresis (BSP) is a neuromuscular disorder which affects both male and female cattle. BSP is characterized by spastic contraction and overextension of the gastrocnemious muscle of one or both limbs and is associated with a scarce increase in body weight. This disease seems to be caused by an autosomal and recessive gene, with incomplete penetration, although no genes clearly involved with its onset have been so far identified. We employed cDNA microarrays to identify metabolic pathways affected by BSP in Romagnola cattle breed. Investigation of those pathways at the genome level can help to understand this disease. RESULTS: Microarray analysis of control and affected individuals resulted in 268 differentially expressed genes. These genes were subjected to KEGG pathway functional clustering analysis, revealing that they are predominantly involved in Cell Communication, Signalling Molecules and Interaction and Signal Transduction, Diseases and Nervous System classes. Significantly enriched KEGG pathway's classes for the differentially expressed genes were calculated; interestingly, all those significantly under-expressed in the affected samples are included in Neurodegenerative Diseases. To identify genome locations possibly harbouring gene(s) involved in the disease, the chromosome distribution of the differentially expressed genes was also investigated. CONCLUSIONS: The cDNA microarray we used in this study contains a brain library and, even if carrying an incomplete transcriptome representation, it has proven to be a valuable tool allowing us to add useful and new information to a poorly studied disease. By using this tool, we examined nearly 15000 transcripts and analysed gene pathways affected by the disease. Particularly, our data suggest also a defective glycinergic synaptic transmission in the development of the disease and an alteration of calcium signalling proteins. We provide data to acquire knowledge of a genetic disease for which literature still presents poor results and that could be further and specifically analysed in the next future. Moreover this study, performed in livestock, may also harbour molecular information useful for understanding human diseases.


Asunto(s)
Enfermedades de los Bovinos/metabolismo , Perfilación de la Expresión Génica/veterinaria , Sistema Nervioso/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos/veterinaria , Paraparesia Espástica/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/genética , Femenino , Expresión Génica/genética , Masculino , Paraparesia Espástica/genética , Paraparesia Espástica/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/genética
16.
Animals (Basel) ; 13(4)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36830374

RESUMEN

Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of paratuberculosis (PTB), a widespread chronic enteritis of ruminants. The progression of the infection depends on the containment action of innate and cell-mediated immunity (CMI), and it is related to environmental and genetic factors. In particular, PTB susceptibility seems to be associated with specific genes coding for immune regulators involved in the cell-mediated response during the infection. The aim of this preliminary study was to verify, in Italian beef cattle, an association between MAP infectious status and the presence of single nucleotide polymorphisms (SNPs) in candidate genes. To the best of our knowledge, this is the first investigation conducted on a native beef cattle breed, known as Marchigiana, reared in Central Italy. The present research, based on a longitudinal study, aimed to identify and correlate phenotypic and genetic profiles characteristic of the subjects potentially able to contrast or contain PTB. In a MAP-infected herd, ELISA, IFN-γ tests, qPCR, and cultures were performed at a follow-up, occurring within a period ranging from three to six years, to evaluate the individual state of infection. Animals testing positive for at least one test were considered infected. DNA samples of 112 bovines, with known MAP statuses, were analyzed to verify an association with SNPs in the genes encoding gamma-interferon (BoIFNG), interleukin receptor 10 (IL10RA), interleukin receptor 12 (IL12RB2), and toll-like receptors (TLR1, TLR2, TLR4). Regarding statistical analysis, the differences among target genes and pairs of alleles in the analyzed groups of animals, were evaluated at a significance level of p < 0.05. For IL10RA and for IL12RB2 genes, relevant differences in genotypic frequencies among the considered cattle groups were observed. For all candidate genes studied in this investigation, SNP genotypes already associated with PTB resistance were found more frequently in our population, suggesting potential resistance traits in the Marchigiana breed.

17.
J Chem Theory Comput ; 18(6): 3308-3317, 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35649124

RESUMEN

InteraChem is an ab initio interactive molecular dynamics (AI-IMD) visualizer that leverages recent advances in virtual reality hardware and software, as well as the graphical processing unit (GPU)-accelerated TeraChem electronic structure package, in order to render quantum chemistry in real time. We introduce the exploration of electronically excited states via AI-IMD using the floating occupation molecular orbital-complete active space configuration interaction method. The optimization tools in InteraChem enable identification of excited state minima as well as minimum energy conical intersections for further characterization of excited state chemistry in small- to medium-sized systems. We demonstrate that finite-temperature Hartree-Fock theory is an efficient method to perform ground state AI-IMD. InteraChem allows users to track electronic properties such as molecular orbitals and bond order in real time, resulting in an interactive visualization tool that aids in the interpretation of excited state chemistry data and makes quantum chemistry more accessible for both research and educational purposes.


Asunto(s)
Simulación de Dinámica Molecular , Realidad Virtual , Conformación Molecular , Teoría Cuántica , Programas Informáticos
18.
BMC Vet Res ; 7: 35, 2011 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-21740563

RESUMEN

BACKGROUND: X-linked anhidrotic ectodermal dysplasia is a disorder characterized by abnormal development of tissues and organs of ectodermal origin caused by mutations in the EDA gene. The bovine EDA gene encodes the ectodysplasin A, a membrane protein expressed in keratinocytes, hair follicles and sweat glands, which is involved in the interactions between cell and cell and/or cell and matrix. Four mutations causing ectodermal dysplasia in cattle have been described so far. RESULTS: We identified a new single nucleotide polymorphism (SNP) at the 9th base of exon 8 in the EDA gene in two calves of Holstein Friesian cattle breed affected by ectodermal dysplasia. This SNP is located in the exonic splicing enhancer (ESEs) recognized by SRp40 protein. As a consequence, the spliceosome machinery is no longer able to recognize the sequence as exonic and causes exon skipping. The mutation determines the deletion of the entire exon (131 bp) in the RNA processing, causing a severe alteration of the protein structure and thus the disease. CONCLUSION: We identified a mutation, never described before, that changes the regulation of alternative splicing in the EDA gene and causes ectodermal dysplasia in cattle. The analysis of the SNP allows the identification of carriers that can transmit the disease to the offspring. This mutation can thus be exploited for a rational and efficient selection of unequivocally healthy cows for breeding.


Asunto(s)
Enfermedades de los Bovinos/genética , Displasia Ectodermal Anhidrótica Tipo 1/veterinaria , Ectodisplasinas/genética , Mutación Puntual , Empalme Alternativo , Animales , Secuencia de Bases , Bovinos , Displasia Ectodermal Anhidrótica Tipo 1/genética , Femenino , Variación Genética , Masculino , Datos de Secuencia Molecular , Linaje , Polimorfismo de Nucleótido Simple , ARN/química , ARN/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Alineación de Secuencia
19.
ScientificWorldJournal ; 11: 1641-59, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22125424

RESUMEN

We employed mtDNA and nuclear SNPs to investigate the genetic diversity of sheep breeds of three countries of the Mediterranean basin: Albania, Greece, and Italy. In total, 154 unique mtDNA haplotypes were detected by means of D-loop sequence analysis. The major nucleotide diversity was observed in Albania. We identified haplogroups, A, B, and C in Albanian and Greek samples, while Italian individuals clustered in groups A and B. In general, the data show a pattern reflecting old migrations that occurred in postneolithic and historical times. PCA analysis on SNP data differentiated breeds with good correspondence to geographical locations. This could reflect geographical isolation, selection operated by local sheep farmers, and different flock management and breed admixture that occurred in the last centuries.


Asunto(s)
ADN Mitocondrial/genética , Variación Genética , Polimorfismo de Nucleótido Simple , Ovinos/genética , Albania , Animales , Grecia , Haplotipos , Italia , Análisis de Componente Principal
20.
Nat Comput Sci ; 1(1): 42-45, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38217155

RESUMEN

Over the past decade, artificial intelligence has been propelled forward by advances in machine learning algorithms and computational hardware, opening up myriads of new avenues for scientific research. Nevertheless, virtual assistants and voice control have yet to be widely used in the natural sciences. Here, we present ChemVox, an interactive Amazon Alexa skill that uses speech recognition to perform quantum chemistry calculations. This new application interfaces Alexa with cloud computing and returns the results through a capable device. ChemVox paves the way to making computational chemistry routinely accessible to the wider community.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA