Assessing the gene space in draft genomes

Genome sequencing projects have been initiated for a wide range of eukaryotes. A few projects have reached completion, but most exist as draft assemblies. As one of the main reasons to sequence a genome is to obtain its catalog of genes, an important question is how complete or completable the catalog is in unfinished genomes. To answer this question, we have identified a set of core eukaryotic genes (CEGs), that are extremely highly conserved and which we believe are present in low copy numbers in higher eukaryotes. From an analysis of a phylogenetically diverse set of eukaryotic genome assemblies, we found that the proportion of CEGs mapped in draft genomes provides a useful metric for describing the gene space, and complements the commonly used N50 length and x-fold coverage values

Contributions of the vernacular heritage in the current city. Case study: Santo Domingo Neighborhood, Tuxtla Gutiérrez, Chiapas, Mexico

[EN] The situation of marginality and vulnerability in the historic center of the capital of Chiapas is latent despite its location in the area of the greatest supply of services and urban facilities of the city. Specifically in Santo Domingo neighborhood in Tuxtla Gutiérrez, Chiapas, one of the oldest neighborhoods in the city, there has been a gradual loss of inhabitants since the 90s causing the decline of vernacular heritage and local identity. The commitment to sustainable development in cities worldwide sets as goals various actions that promote a look at the vernacular heritage and its relationship with the environment. However, the model of expansive growth of the city in an uncontrolled manner, moving away from the central city, also moves away from the Sustainable Development Goals.This article is part of a broader investigation in which the development of a methodology is proposed that establishes a specific cataloging system of the earthen architectural heritage of Santo Domingo neighborhood to provide guidelines for its preservation, strengthening and, in turn, of the historic city center, as a basis for redirecting the current city towards sustainable development.Through the analysis and characterization of the buildings built with raw earth and their inhabitants, it deepens in the analysis of the vernacular heritage, in its construction and consolidation of the urban environment, as well as its way of contributing to economic, social, and environmental links.However, the future of the vernacular heritage in urban areas, in this case, Santo Domingo neighborhood, depends not only on the patrimonial valuation in society but also on its economic revaluation by public and private institutions.Parra Zebadúa, A.; Genis Vinyals, M.; Ocampo García, L.; Villers Aispuro, R.; Zenteno Hernández, M.; Escamirosa Montalvo, L.; Zebadúa Velasco, S. (2022). Contributions of the vernacular heritage in the current city. Case study: Santo Domingo Neighborhood, Tuxtla Gutiérrez, Chiapas, Mexico. Editorial Universitat Politècnica de València. 287-292. https://doi.org/10.4995/HERITAGE2022.2022.1513128729

Gene finding in the chicken genome

BACKGROUND: Despite the continuous production of genome sequence for a number of organisms, reliable, comprehensive, and cost effective gene prediction remains problematic. This is particularly true for genomes for which there is not a large collection of known gene sequences, such as the recently published chicken genome. We used the chicken sequence to test comparative and homology-based gene-finding methods followed by experimental validation as an effective genome annotation method. RESULTS: We performed experimental evaluation by RT-PCR of three different computational gene finders, Ensembl, SGP2 and TWINSCAN, applied to the chicken genome. A Venn diagram was computed and each component of it was evaluated. The results showed that de novo comparative methods can identify up to about 700 chicken genes with no previous evidence of expression, and can correctly extend about 40% of homology-based predictions at the 5' end. CONCLUSIONS: De novo comparative gene prediction followed by experimental verification is effective at enhancing the annotation of the newly sequenced genomes provided by standard homology-based methods

Genomic Validation of Endometrial Cancer Patient-Derived Xenograft Models as a Preclinical Tool

Bioinformatics; Endometrial cancer; Molecular markerBioinformática; Cáncer endometrial; Marcador molecularBioinformàtica; Càncer d'endometri; Marcador molecularEndometrial cancer (EC) is the second most frequent gynecological cancer worldwide. Although improvements in EC classification have enabled an accurate establishment of disease prognosis, women with a high-risk or recurrent EC face a dramatic situation due to limited further treatment options. Therefore, new strategies that closely mimic the disease are required to maximize drug development success. Patient-derived xenografts (PDXs) are widely recognized as a physiologically relevant preclinical model. Hence, we propose to molecularly and histologically validate EC PDX models. To reveal the molecular landscape of PDXs generated from 13 EC patients, we performed histological characterization and whole-exome sequencing analysis of tumor samples. We assessed the similarity between PDXs and their corresponding patient’s tumor and, additionally, to an extended cohort of EC patients obtained from The Cancer Genome Atlas (TCGA). Finally, we performed functional enrichment analysis to reveal differences in molecular pathway activation in PDX models. We demonstrated that the PDX models had a well-defined and differentiated molecular profile that matched the genomic profile described by the TCGA for each EC subtype. Thus, we validated EC PDX’s potential to reliably recapitulate the majority of histologic and molecular EC features. This work highlights the importance of a thorough characterization of preclinical models for the improvement of the success rate of drug-screening assays for personalized medicine.This research was funded by grants from the Instituto de Salud Carlos III (ISCIII) grant number PI17/02071, PI20/01566, and from the Ministerio de ciencia, Innovación y Universidades through a RETOS Colaboración (RTC-2017-6261-1), both co-financed by the European Regional Development Fund (FEDER); from Fundación Científica Asociación Española Contra el Cáncer (AECC) grant number GCTRA1804MATI, Biomedical Research Center Network (CIBERONC) grant number CB16/12/00328 and Generalitat de Catalunya, grant number 2017SGR1661. B.V.-M. is supported by a predoctoral fellowship (PERIS-SLT017/20/000183) from Generalitat de Catalunya. E.C. is supported by an Investigator Grant from AECC (INVES20051COLA)

SelenoDB 2.0: annotation of selenoprotein genes in animals and their genetic diversity in humans

SelenoDB (http://www.selenodb.org) aims to provide high-quality annotations of selenoprotein genes, proteins and SECIS elements. Selenoproteins are proteins that contain the amino acid selenocysteine (Sec) and the first release of the database included annotations for eight species. Since the release of SelenoDB 1.0 many new animal genomes have been sequenced. The annotations of selenoproteins in new genomes usually contain many errors in major databases. For this reason, we have now fully annotated selenoprotein genes in 58 animal genomes. We provide manually curated annotations for human selenoproteins, whereas we use an automatic annotation pipeline to annotate selenoprotein genes in other animal genomes. In addition, we annotate the homologous genes containing cysteine (Cys) instead of Sec. Finally, we have surveyed genetic variation in the annotated genes in humans. We use exon capture and resequencing approaches to identify single nucleotide polymorphisms in more than 50 human populations around the world. We thus present a detailed view of the genetic divergence of Sec- and Cys-containing genes in animals and their diversity in humans. The addition of these data sets into the second release of the database provides a valuable resource for addressing medical and evolutionary questions in selenium biology

Erratum: Corrigendum: Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution

International Chicken Genome Sequencing Consortium. The Original Article was published on 09 December 2004. Nature432, 695–716 (2004). In Table 5 of this Article, the last four values listed in the ‘Copy number’ column were incorrect. These should be: LTR elements, 30,000; DNA transposons, 20,000; simple repeats, 140,000; and satellites, 4,000. These errors do not affect any of the conclusions in our paper. Additional information. The online version of the original article can be found at 10.1038/nature0315

WISCOD: A Statistical Web-Enabled Tool for the Identification of Significant Protein Coding Regions

Classically, gene prediction programs are based on detecting signals such as boundary sites (splice sites, starts, and stops) and coding regions in the DNA sequence in order to build potential exons and join them into a gene structure. Although nowadays it is possible to improve their performance with additional information from related species or/and cDNA databases, further improvement at any step could help to obtain better predictions. Here, we present WISCOD, a web-enabled tool for the identification of significant protein coding regions, a novel software tool that tackles the exon prediction problem in eukaryotic genomes. WISCOD has the capacity to detect real exons from large lists of potential exons, and it provides an easy way to use global P value called expected probability of being a false exon (EPFE) that is useful for ranking potential exons in a probabilistic framework, without additional computational costs. The advantage of our approach is that it significantly increases the specificity and sensitivity (both between 80% and 90%) in comparison to other ab initio methods (where they are in the range of 70–75%). WISCOD is written in JAVA and R and is available to download and to run in a local mode on Linux and Windows platforms

Vol. 23 no. 9 2007, pages 1061–1067 BIOINFORMATICS ORIGINAL PAPER doi:10.1093/bioinformatics/btm071

Motivation: The numbers of finished and ongoing genome projects are increasing at a rapid rate, and providing the catalog of genes for these new genomes is a key challenge. Obtaining a set of wellcharacterized genes is a basic requirement in the initial steps of any genome annotation process. An accurate set of genes is needed in order to learn about species-specific properties, to train gene-finding programs, and to validate automatic predictions. Unfortunately, many new genome projects lack comprehensive experimental data to derive a reliable initial set of genes. Results: In this study, we report a computational method, CEGMA (Core Eukaryotic Genes Mapping Approach), for building a highly reliable set of gene annotations in the absence of experimental data. We define a set of conserved protein families that occur in a wide range of eukaryotes, and present a mapping procedure that accurately identifies their exon–intron structures in a novel genomic sequence. CEGMA includes the use of profile-hidden Markov models to ensure the reliability of the gene structures. Our procedure allows one to build an initial set of reliable gene annotations in potentially any eukaryotic genome, even those in draft stages. Availability: Software and data sets are available online a

Promoter-Proximal Introns in Arabidopsis thaliana Are Enriched in Dispersed Signals that Elevate Gene Expression[W][OA]

Introns that elevate mRNA accumulation have been found in a wide range of eukaryotes. However, not all introns affect gene expression, and direct testing is currently the only way to identify stimulatory introns. Our genome-wide analysis in Arabidopsis thaliana revealed that promoter-proximal introns as a group are compositionally distinct from distal introns and that the degree to which an individual intron matches the promoter-proximal intron profile is a strong predictor of its ability to increase expression. We found that the sequences responsible for elevating expression are dispersed throughout an enhancing intron, as is a candidate motif that is overrepresented in first introns and whose occurrence in tested introns is proportional to its effect on expression. The signals responsible for intron-mediated enhancement are apparently conserved between Arabidopsis and rice (Oryza sativa) despite the large evolutionary distance separating these plants