The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Standard likelihood-based frameworks in phylogenetics consider the process of evolution of a sequence site by site. Assuming that sites evolve independently greatly simplifies the required calculations. However, this simplification is known to be incorrect in many cases. Here, a computational method that allows for general dependence between sites of a sequence is investigated. Using this method,...
In several works it has been shown that the interplay between short range and long range interactions, mimicking the hydrophobic effect, leads to the formation of the typical secondary structures in proteins, alpha-helices and beta-sheets. In this work we study in detail how the general properties of the energy landscape emerge in a model that presents both components. In this regard it proves useful...
We discuss recent developments in the modeling of negative autoregulated genetic networks. In particular, we consider the temporal evolution of the population of mRNA and proteins in simple networks using rate equations. In the limit of low copy numbers, fluctuation effects become significant and more adequate modeling is then achieved using the master equation formalism. The analogy between regulatory...
In bioinformatics, binding of transcription regulatory factors to the cognate binding sites is usually described by sequence-specific binding energy, which is estimated from a training sample of sites. This model implies that all binding sites with binding energy above some threshold are functional and site sequence variations should be considered neutral until they do not reduce this energy below...
The combination of genomic, proteomic and other data, enables to reconstruct the evolution of complex cellular units thus transcending the more reductionistic view of traditional molecular phylogeny. However, most models which try to investigate the evolution of protein interaction networks so far are based on the analysis of their global statistical properties, such as their scale-free behaviour...
The evolution of RNA viruses under antiviral pressure is characterized by high mutation rates and strong selective forces that induce extremely rapid changes of protein sequences. This makes the course of molecular evolution directly observable on time scales of months. Here we study the interplay between selection for drug resistance and selection for thermodynamic stability in the protease (PR)...
MIKC-type proteins represent a class of MADS-domain transcription factors and are defined by a unique domain structure: in addition to the highly conserved DNA-binding MADS-domain, they have three other domains (‘I’, ‘K’ and ‘C’), with the keratin-like K-domain being the most highly conserved and characteristic one. The number and functional diversity of MIKC-type proteins increased considerably during...
The Squalius alburnoides complex, of hybrid origin, comprises diploid, triploid and tetraploid forms and has a widespread distribution in the Iberian waters. The southern populations of this complex, sympatric with S. pyrenaicus, show high genetic variability, diversity of forms and reproductive modes which create pathways that may allow for the establishment of a new species in the future. Here we...
We review and further develop an analytical model that describes how thermodynamic constraints on the stability of the native state influence protein evolution in a site-specific manner. To this end, we represent both protein sequences and protein structures as vectors: structures are represented by the principal eigenvector (PE) of the protein contact matrix, a quantity that resembles closely the...
The peroxisome proliferator-activated receptor (PPAR) γ is regarded as a “master regulator” of adipocyte differentiation and is abundantly expressed in adipose. To understand the biological role of PPARγ in adipose, RNA interference (RNAi) of PPARγ should be a powerful tool. 3T3-L1 cell line serves an excellent model to investigate the mechanism of preadipocyte-to-adipocyte differentiation. However,...
Transcriptional profiles of an alveolar rhabdomyosarcoma (RMS) and of a RMS cell line were reconstructed by a computational and statistical approach. Expression data of 29,963 genes in 11 adult human healthy tissues and in 37 tumour tissues were analysed for comparison. We identified 202 genes differentially expressed in at least one RMS sample, as compared with normal skeletal muscle. Among them,...
The mammalian glycinamide ribonucleotide formyltransferase (GART) genes encode a trifunctional polypeptide involved in the de novo purine biosynthesis. We isolated a bacterial artificial chromosome (BAC) clone containing the bovine GART gene and determined the complete DNA sequence of the BAC clone. Cloning and characterization of the bovine GART gene revealed that the bovine gene consists of 23 exons...
PIMT, a transcriptional coactivator which interacts with and enhances nuclear receptor coactivator PRIP function, was identified recently in mammalian cells and suggested to function as a link between two major multiprotein complexes anchored by CBP/p300 and PBP. Here we describe that the gene of the Drosophila homologue of PIMT, designated as Dtl, is closely associated and has an overlapping promoter...
Transcription of the PDGF-A chain gene is regulated by multiple promoter and silencer elements that are GC-rich and exhibit considerable single-stranded character. In this study, the 42 kDa single-stranded DNA and RNA binding protein, Purα, was investigated with respect to its ability to bind and interact functionally with single-stranded DNA elements in the PDGF-A gene. Recombinant GST-Purα bound...
As the prototype of a family of transcription factors, Sp1 has been extensively studied and widely reported for its role in gene regulation. The first evidence of Sp1 phosphorylation was reported more than a decade ago. Since then, an increasing number of Sp1 phosphorylation events have been characterized. Recent data demonstrate an important role for the phosphorylation state of Sp1 in the regulation...
We have characterized the regulation of human SH-2 containing inositol 5′-phosphatase 2 (SHIP2) gene expression. First, the transcription initiation sites and the sequence of the 5′ upstream region of human SHIP2 gene were elucidated. Next, the minimal promoter of the human SHIP2 gene was identified by reporter gene assays in HL60 cells and differentiated human subcutaneous white adipocytes. An Sp1...
We have studied the effects of methylation of the promoter region on the expression of human synaptotagmin XI (syt11), a gene implicated in the onset of schizophrenia. Sequence analysis showed that cytosine residues not in the CpG sequence, but still within the promoter region of the gene, are partially methylated. The methylated cytosine residues are located in the mRNA-coding (minus) strand of the...
The fork-head type transcription factors are a class of regulators that function in a broad spectrum of cellular and developmental processes in many species ranging from yeasts to human. Previous data on yeast fork-head genes suggested roles for these regulators in the control of cell division, sexual differentiation and development. The genome of Schizosaccharomyces pombe has four genes that code...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.