共查询到20条相似文献,搜索用时 15 毫秒
1.
Julia M Gohlke Reuben Thomas Yonqing Zhang Michael C Rosenstein Allan P Davis Cynthia Murphy Kevin G Becker Carolyn J Mattingly Christopher J Portier 《BMC systems biology》2009,3(1):46
Background
Pathogenesis of complex diseases involves the integration of genetic and environmental factors over time, making it particularly difficult to tease apart relationships between phenotype, genotype, and environmental factors using traditional experimental approaches. 相似文献2.
3.
Julián Mensch Nicolás Lavagnino Valeria Paula Carreira Ana Massaldi Esteban Hasson Juan José Fanara 《BMC developmental biology》2008,8(1):78
Background
Understanding the genetic architecture of ecologically relevant adaptive traits requires the contribution of developmental and evolutionary biology. The time to reach the age of reproduction is a complex life history trait commonly known as developmental time. In particular, in holometabolous insects that occupy ephemeral habitats, like fruit flies, the impact of developmental time on fitness is further exaggerated. The present work is one of the first systematic studies of the genetic basis of developmental time, in which we also evaluate the impact of environmental variation on the expression of the trait. 相似文献4.
Carlos Isaza Julieta Henao José H Isaza Martínez Juan C Sepúlveda Arias Leonardo Beltrán 《BMC clinical pharmacology》2007,7(1):6
Background
Omeprazole is metabolized by the hepatic cytochrome P450 (CYP) 2C19 enzyme to 5-hydroxyomeprazole. CYP2C19 exhibits genetic polymorphisms responsible for the presence of poor metabolizers (PMs), intermediate metabolizers (IMs) and extensive metabolizers (EMs). The defective mutations of the enzyme and their frequencies change between different ethnic groups; however, the polymorphism of the CYP2C19 gene has not been studied in Colombian mestizos. The aim of this study was to evaluate the genotype and phenotype status of CYP2C19 in Colombian mestizos, in order to contribute to the use of appropriate strategies of drug therapy for this population. 相似文献5.
We propose a principle of consistency between different hierarchical levels of biological systems. Given a consistency between
molecule replication and cell reproduction, universal statistical laws on cellular chemical abundances are derived and confirmed
experimentally. They include a power law distribution of gene expressions, a lognormal distribution of cellular chemical abundances
over cells, and embedding of the power law into the network connectivity distribution. Second, given a consistency between
genotype and phenotype, a general relationship between phenotype fluctuations by genetic variation and isogenic phenotypic
fluctuation by developmental noise is derived. Third, we discuss the chaos mechanism for stem cell differentiation with autonomous
regulation, resulting from a consistency between cell reproduction and growth of the cell ensemble.
相似文献
Kunihiko KanekoEmail: |
6.
Gaetano Donofrio Antonio Capocefalo Valentina Franceschi Giorgio Morini Maurizio Del Bue Virna Conti Sandro Cavirani Stefano Grolli 《BMC cell biology》2010,11(1):73
Background
Adipose-Derived Stromal Cells have been shown to have multiple lineage differentiation properties and to be suitable for tissues regeneration in many degenerative processes. Their use has been proposed for the therapy of joint diseases and tendon injuries in the horse. In the present report the genetic manipulation of Equine Adipose-Derived Stromal Cells has been investigated. 相似文献7.
Background
Organisms live in environments that vary. For life-history traits that vary across environments, fitness will be maximised when the phenotype is appropriately matched to the environmental conditions. For the free-living nematode Caenorhabditis elegans, we have investigated how two major life-history traits, (i) the development of environmentally resistant dauer larvae and (ii) reproduction, respond to environmental stress (high population density and low food availability), and how these traits vary between lines and the genetic basis of this variation. 相似文献8.
Louis Lambrechts Christine Chevillon Rebecca G Albright Butsaya Thaisomboonsuk Jason H Richardson Richard G Jarman Thomas W Scott 《BMC evolutionary biology》2009,9(1):160-11
Background
Several observations support the hypothesis that vector-driven selection plays an important role in shaping dengue virus (DENV) genetic diversity. Clustering of DENV genetic diversity at a particular location may reflect underlying genetic structure of vector populations, which combined with specific vector genotype × virus genotype (G × G) interactions may promote adaptation of viral lineages to local mosquito vector genotypes. Although spatial structure of vector polymorphism at neutral genetic loci is well-documented, existence of G × G interactions between mosquito and virus genotypes has not been formally demonstrated in natural populations. Here we measure G × G interactions in a system representative of a natural situation in Thailand by challenging three isofemale families from field-derived Aedes aegypti with three contemporaneous low-passage isolates of DENV-1. 相似文献9.
Background
Ciliary neurotrophic factor (CNTF) is important for neuronal and muscle development, and genetic variation in the CNTF gene has been associated with muscle strength. The effect of CNTF on nerve development suggests that CNTF genotype may be associated with force production via its influence on motor unit size and firing patterns. The purpose of this study is to examine whether CNTF genotype differentially affects motor unit activation in the vastus medialis with increasing isometric force during knee extension. 相似文献10.
Hugh Ramsay Ian Kelleher Padraig Flannery Mary C. Clarke Fionnuala Lynch Michelle Harley Dearbhla Connor Carol Fitzpatrick Derek W. Morris Mary Cannon 《PloS one》2013,8(11)
Objective
Psychotic experiences occur at a much greater prevalence in the population than psychotic disorders. There has been little research to date, however, on genetic risk for this extended psychosis phenotype. We examined whether COMT or BDNF genotypes were associated with psychotic experiences or interacted with childhood trauma in predicting psychotic experiences.Method
Psychiatric interviews and genotyping for COMT-Val158Met and BDNF-Val66Met were carried out on two population-based samples of 237 individuals aged 11-15 years. Logistic regression was used to examine for main effects by genotype and childhood trauma, controlling for important covariates. This was then compared to a model with a term for interaction between genotype and childhood trauma. Where a possible interaction was detected, this was further explored in stratified analyses.Results
While childhood trauma showed a borderline association with psychotic experiences, COMT-Val158Met and BDNF-Val66Met genotypes were not directly associated with psychotic experiences in the population. Testing for gene x environment interaction was borderline significant in the case of COMT-Val158Met with individuals with the COMT-Val158Met Val-Val genotype, who had been exposed to childhood trauma borderline significantly more likely to report psychotic experiences than those with Val-Met or Met-Met genotypes. There was no similar interaction by BDNF-Val66Met genotype.Conclusion
The COMT-Val158Met Val-Val genotype may be a genetic moderator of risk for psychotic experiences in individuals exposed to childhood traumatic experiences. 相似文献11.
Background
Agave tequilana Weber var. azul, is the only one variety permitted by federal law in México to be used for tequila production which is the most popular contemporary alcoholic beverage made from agave and recognized worldwide. Despite the economic, genetic, and ornamental value of the plant, it has not been subjected to detailed cytogenetic research, which could lead to a better understanding of its reproduction for future genetic improvement. 相似文献12.
Yuval Itan Bryony L Jones Catherine JE Ingram Dallas M Swallow Mark G Thomas 《BMC evolutionary biology》2010,10(1):36
Background
The ability of adult humans to digest the milk sugar lactose - lactase persistence - is a dominant Mendelian trait that has been a subject of extensive genetic, medical and evolutionary research. Lactase persistence is common in people of European ancestry as well as some African, Middle Eastern and Southern Asian groups, but is rare or absent elsewhere in the world. The recent identification of independent nucleotide changes that are strongly associated with lactase persistence in different populations worldwide has led to the possibility of genetic tests for the trait. However, it is highly unlikely that all lactase persistence-associated variants are known. Using an extensive database of lactase persistence phenotype frequencies, together with information on how those data were collected and data on the frequencies of lactase persistence variants, we present a global summary of the extent to which current genetic knowledge can explain lactase persistence phenotype frequency. 相似文献13.
Yan-Fung Wong Qing Sheng Janet WL Chung Jacky KF Chan King L Chow 《BMC developmental biology》2010,10(1):82
Background
C. elegans TGF-β-like Sma/Mab signaling pathway regulates both body size and sensory ray patterning. Most of the components in this pathway were initially identified by genetic screens based on the small body phenotype, and many of these mutants display sensory ray patterning defect. At the cellular level, little is known about how and where these components work although ray structural cell has been implicated as one of the targets. Based on the specific ray patterning abnormality, we aim to identify by RNAi approach additional components that function specifically in the ray lineage to elucidate the regulatory role of TGF-β signaling in ray differentiation. 相似文献14.
Isabel Rocha Paulo Maia Pedro Evangelista Paulo Vilaça Simão Soares José P Pinto Jens Nielsen Kiran R Patil Eugénio C Ferreira Miguel Rocha 《BMC systems biology》2010,4(1):45
Background
Over the last few years a number of methods have been proposed for the phenotype simulation of microorganisms under different environmental and genetic conditions. These have been used as the basis to support the discovery of successful genetic modifications of the microbial metabolism to address industrial goals. However, the use of these methods has been restricted to bioinformaticians or other expert researchers. The main aim of this work is, therefore, to provide a user-friendly computational tool for Metabolic Engineering applications. 相似文献15.
Background
A metabolism is a complex network of chemical reactions. This network synthesizes multiple small precursor molecules of biomass from chemicals that occur in the environment. The metabolic network of any one organism is encoded by a metabolic genotype, defined as the set of enzyme-coding genes whose products catalyze the network's reactions. Each metabolic genotype has a metabolic phenotype. We define this metabolic phenotype as the spectrum of different sources of a chemical element that a metabolism can use to synthesize biomass. We here focus on the element sulfur. We study properties of the space of all possible metabolic genotypes in sulfur metabolism by analyzing random metabolic genotypes that are viable on different numbers of sulfur sources. 相似文献16.
Jin-Xiang Yuan Li-Juan Xiao Cui-Ling Lu Xue-Sen Zhang Tao Liu Min Chen Zhao-Yuan Hu Fei Gao Yi-Xun Liu 《Reproductive biology and endocrinology : RB&E》2009,7(1):23-10
Background
Heat shock proteins (Hsps) are a set of highly conserved proteins, Hsp105, has been suggested to play a role in reproduction. 相似文献17.
Owing to the relevance to evolutionary theories of genotypic and phenotypic evolution, the correspondence of differentiation among natural populations in complex phenotypic traits and genetic markers has been studied extensively, and generally found to be poor. In contrast, the correspondence of differentiation among natural populations in gene expression, now often considered a genomic era proxy for the phenotype, and genetic markers, remains largely unexplored. Here, an analysis of expression and nucleotide sequence polymorphism of 106 genes in Drosophila melanogaster strains of the Cosmopolitan (M) and Zimbabwe, Africa (Z) mating races showed that differentiation of gene expression and of coding sequences, measured as QST and GST, respectively, were uncorrelated and, generally, QST > GST. However, an exploratory analysis showed that GST of the 5 prime sequences of genes was correlated with QST calculated from expression data, while GST of the coding sequences remained uncorrelated with QST. This scenario is consistent with the population differentiation at cis-regulatory regions that is decoupled from differentiation of the coding regions. However, despite evidence for selection on global levels of gene expression (deduced from QST > GST), 5 prime sequence polymorphisms generally were compatible with selective neutrality, suggesting differentiation in cis-regulated gene expression for these genes has been promoted by drift or selection too weak or too long ago to be detected, or higher organizational levels underlying the genetic architecture of expression are targets of selection. In all, this raises the question how selection on the expression changes (i.e. the phenotype) can be so obvious yet elusive at the level of the nucleotide sequence. Our contrasts between genetic differentiation of populations in expression and sequences revealed that even when genotype and phenotype can be connected the sources of variation that are the target of selection remain to be identified. 相似文献
18.
Background
Systematic analyses of loss-of-function phenotypes have been carried out for most genes in Saccharomyces cerevisiae, Caenorhabditis elegans, and Drosophila melanogaster. Although such studies vastly expand our knowledge of single gene function, they do not address redundancy in genetic networks. Developing tools for the systematic mapping of genetic interactions is thus a key step in exploring the relationship between genotype and phenotype. 相似文献19.
Rute ST Martins Laurence AM Deloffre Constantinos C Mylonas Deborah M Power Adelino VM Canário 《Reproductive biology and endocrinology : RB&E》2007,5(1):19
Background
DAX1 (NR0B1), a member of the nuclear receptors super family, has been shown to be involved in the genetic sex determination and in gonadal differentiation in several vertebrate species. In the aquaculture fish European sea bass, Dicentrarchus labrax, and in the generality of fish species, the mechanisms of sex determination and differentiation have not been elucidated. The present study aimed at characterizing the European DAX1 gene and its developmental expression at the mRNA level. 相似文献20.
Estefanía Calvo-álvarez Raquel álvarez-Velilla Maribel Jiménez Ricardo Molina Yolanda Pérez-Pertejo Rafael Bala?a-Fouce Rosa M. Reguera 《PLoS neglected tropical diseases》2014,8(9)