0000000000075635
AUTHOR
Manuel Pérez-alonso
showing 36 related works from this author
Lack of association between proliferative verrucous leukoplakia and human papillomavirus infection.
2005
Purpose To analyze proliferative verrucous leukoplakia (PVL) for the presence of human papillomavirus (HPV) in different stages of the disease. Materials and Methods We studied 13 patients with PVL. In 10 patients (76.9%), a lesional biopsy was taken and frozen at −40°C. Four patients were instructed to mouth rinse with sterile sera. The biopsy and rinse samples were analyzed for HPV by PCR. Results We did not detect HPV infection in the PVL tissue or in the oral rinse of any of the 13 patients in any stage of the disease analyzed, neither in oral squamous cell carcinoma nor in the simple hyperkeratosis. Conclusion There was no association between PVL and HPV infection in our patients.
A FRET-based assay for characterization of alternative splicing events using peptide nucleic acid fluorescence in situ hybridization
2009
We describe a quantitative method for detecting RNA alternative splicing variants that combines in situ hybridization of fluorescently labeled peptide nucleic acid (PNA) probes with confocal microscopy Förster resonance energy transfer (FRET). The use of PNA probes complementary to sequences flanking a given splice junction allows to specifically quantify, within the cell, the RNA isoform generating such splice junction by FRET measure. As a proof of concept we analyzed two alternative splicing events originating from lymphocyte antigen 6 (LY6) complex, locus G5B (LY6G5B) pre-mRNA. These are characterized by the removal of the first intron (Fully Spliced Isoform, FSI) or by retention of suc…
Pentamidine rescues contractility and rhythmicity in a Drosophila model of myotonic dystrophy heart dysfunction
2015
Up to 80% of individuals with myotonic dystrophy type 1 (DM1) will develop cardiac abnormalities at some point during the progression of their disease, the most common of which is heart blockage of varying degrees. Such blockage is characterized by conduction defects and supraventricular and ventricular tachycardia, and carries a high risk of sudden cardiac death. Despite its importance, very few animal model studies have focused on the heart dysfunction in DM1. Here, we describe the characterization of the heart phenotype in a Drosophila model expressing pure expanded CUG repeats under the control of the cardiomyocyte-specific driver GMH5-Gal4. Morphologically, expression of 250 CUG repeat…
Prevalencia de fibrilación auricular y uso de fármacos antitrombóticos en el paciente hipertenso ≥ 65 años. El registro FAPRES.
2009
Introduccion y objetivos Entre los principales factores asociados a la presencia de fibrilacion auricular y mayor riesgo embolico estan la edad y la hipertension arterial. Nuestro objetivo es conocer la prevalencia de fibrilacion auricular en el paciente hipertenso de 65 o mas anos de edad en la Comunidad Valenciana y el empleo de farmacos antitromboticos. Metodos Cada investigador incluyo a los primeros 3 pacientes hipertensos de edad ≥ 65 anos que acudian a la consulta el primer dia de la semana durante 5 semanas. Se recogieron los factores de riesgo, la historia cardiovascular, la puntuacion CHADS2 y el tratamiento farmacologico y se realizo un electrocardiograma para su analisis central…
Successful application of preimplantation genetic diagnosis for hypokalaemic periodic paralysis.
2009
Hypokalaemic periodic paralysis is a rare dominant inherited disease where a person suffers sudden falls of circulating potassium concentrations, producing muscle weakness and sometimes severe paralysis. Attacks can occur as frequently as several times a day or once in a year. The age of onset is usually adolescence but symptoms can appear as early as 10 years of age. Muscle weakness can compromise vital functions such as breathing or swallowing and heart arrhythmias are also frequent during attacks. Preimplantation genetic diagnosis, an early form of prenatal diagnosis for couples at risk of transmitting inherited diseases, was used to prevent the transmission of this disease. Six polymorp…
Sequencing analysis of a 4·1 kb subtelomeric region from yeast chromosome IV identifiesHXT15, a new member of the hexose transporter family
1996
The DNA sequence of a 4·1 kb region of Saccharomyces cerevisiae chromosome IV was determined. This region contains a single open reading frame which codes for a member of the hexose transporter family. This new gene has been named HXT15 according to yeast gene data bases. The sequence has been entered in the EMBL data library under Accession Number X92891.
Development of aDrosophila melanogasterspliceosensor system forin vivohigh-throughput screening in myotonic dystrophy type 1
2014
AbstractAlternative splicing of pre-mRNAs is an important mechanism that regulates cellular function in higher eukaryotes. A growing number of human genetic diseases involve splicing defects that are directly connected to their pathology. In myotonic dystrophy type 1 (DM1), several clinical manifestations have been proposed to be the consequence of tissue-specific missplicing of numerous genes. These events are triggered by an RNA gain-of-function and resultant deregulation of specific RNA-binding factors, such as the nuclear sequestration of muscleblind-like family factors (MBNL1-MBNL3). Thus, the identification of chemical modulators of splicing events could lead to the development of the…
Expanded CCUG repeat RNA expression in Drosophila heart and muscle trigger Myotonic Dystrophy type 1-like phenotypes and activate autophagocytosis ge…
2016
AbstractMyotonic dystrophies (DM1–2) are neuromuscular genetic disorders caused by the pathological expansion of untranslated microsatellites. DM1 and DM2, are caused by expanded CTG repeats in the 3′UTR of the DMPK gene and CCTG repeats in the first intron of the CNBP gene, respectively. Mutant RNAs containing expanded repeats are retained in the cell nucleus, where they sequester nuclear factors and cause alterations in RNA metabolism. However, for unknown reasons, DM1 is more severe than DM2. To study the differences and similarities in the pathogenesis of DM1 and DM2, we generated model flies by expressing pure expanded CUG ([250]×) or CCUG ([1100]×) repeats, respectively, and compared …
Oligonucleotide probes detect splicing variants insituinDrosophilaembryos
1992
We describe a method for the in situ detection of specific splicing variants. The method is based on the use of antisense oligonucleotides designed to span splice junctions labelled with digoxigenin by terminal transferase tailing. We find that the spatial patterns of Ubx splicing variants Ia and IIa are similar in early embryos, but differ in late embryos. Variant IVa is only detected in the CNS (ps6) at stages 16 and 17. We also present evidence indicating that the first splicing event is cotranscriptional.
The muscleblind gene participates in the organization of Z-bands and epidermal attachments of Drosophila muscles and is regulated by Dmef2.
1998
We report the embryonic phenotype of muscleblind (mbl), a recently described Drosophila gene involved in terminal differentiation of adult ommatidia. mbl is a nuclear protein expressed late in the embryo in pharyngeal, visceral, and somatic muscles, the ventral nerve cord, and the larval photoreceptor system. All three mbl alleles studied exhibit a lethal phenotype and die as stage 17 embryos or first instar larvae. These larvae are partially paralyzed, show a characteristically contracted abdomen, and lack striation of muscles. Our analysis of the somatic musculature shows that the pattern of muscles is established correctly, and they form morphologically normal synapses. Ultrastructural a…
Sequence and analysis of chromosome 3 of the plant Arabidopsis thaliana.
2000
Arabidopsis thaliana is an important model system for plant biologists. In 1996 an international collaboration (the Arabidopsis Genome Initiative) was formed to sequence the whole genome of Arabidopsis and in 1999 the sequence of the first two chromosomes was reported. The sequence of the last three chromosomes and an analysis of the whole genome are reported in this issue. Here we present the sequence of chromosome 3, organized into four sequence segments (contigs). The two largest (13.5 and 9.2 Mb) correspond to the top (long) and the bottom (short) arms of chromosome 3, and the two small contigs are located in the genetically defined centromere. This chromosome encodes 5,220 of the rough…
The Arabidopsis CBF Gene Family Is Composed of Three Genes Encoding AP2 Domain-Containing Proteins Whose Expression Is Regulated by Low Temperature b…
1999
Abstract We have identified two genes from Arabidopsis that show high similarity withCBF1, a gene encoding an AP2 domain-containing transcriptional activator that binds to the low-temperature-responsive element CCGAC and induces the expression of some cold-regulated genes, increasing plant freezing tolerance. These two genes, which we have named CBF2 and CBF3, also encode proteins containing AP2 DNA-binding motifs. Furthermore, like CBF1, CBF2 and CBF3 proteins also include putative nuclear-localization signals and potential acidic activation domains. The CBF2 andCBF3 genes are linked to CBF1,constituting a cluster on the bottom arm of chromosome IV. The high level of similarity among the t…
In silico discovery of substituted pyrido[2,3-d]pyrimidines and pentamidine-like compounds with biological activity in myotonic dystrophy models
2016
Myotonic dystrophy type 1 (DM1) is a rare multisystemic disorder associated with an expansion of CUG repeats in mutant DMPK (dystrophia myotonica protein kinase) transcripts; the main effect of these expansions is the induction of pre-mRNA splicing defects by sequestering muscleblind-like family proteins (e.g. MBNL1). Disruption of the CUG repeats and the MBNL1 protein complex has been established as the best therapeutic approach for DM1, hence two main strategies have been proposed: targeted degradation of mutant DMPK transcripts and the development of CUG-binding molecules that prevent MBNL1 sequestration. Herein, suitable CUG-binding small molecules were selected using in silico approach…
**Arabidopsis thaliana** sequence analysis confirms the presence of cyt b-561 in plants: evidence for a novel protein family
2000
Recent advances in the Arabidopsis sequencing project has elucidated the presence of two genes Atb561-A and Atb561-B that show limited homology to the DNA sequence encoding for the mammalian chromaffin granule cytochrome b-561 (cyt b-561). Detailed analysis of the structural features and conserved residues reveals, however, that the structural homology between the presumptive Arabidopsis proteins and the animal proteins is very high. All proteins are hydrophobic and show highly conserved transmembrane helices. The presumably heme-binding histidine residues in the plant and animal sequences as well as the suggested binding site for the electron acceptor, monodehydroascorbate, are strictly co…
Six Serum miRNAs Fail to Validate as Myotonic Dystrophy Type 1 Biomarkers.
2016
Myotonic dystrophy type 1 (DM1) is an autosomal dominant genetic disease caused by expansion of a CTG microsatellite in the 3' untranslated region of the DMPK gene. Despite characteristic muscular, cardiac, and neuropsychological symptoms, CTG trinucleotide repeats are unstable both in the somatic and germinal lines, making the age of onset, clinical presentation, and disease severity very variable. A molecular biomarker to stratify patients and to follow disease progression is, thus, an unmet medical need. Looking for a novel biomarker, and given that specific miRNAs have been found to be misregulated in DM1 heart and muscle tissues, we profiled the expression of 175 known serum miRNAs in …
Molecular characterization of the zerknüllt region of the Antennapedia complex of D. subobscura.
1995
We have characterized at the molecular level the zerknullt (zen) region of the Drosophila subobscura Antennapedia complex. The sequence comparison between D. subobscura and D. melanogaster shows an irregular distribution of the conserved and diverged regions, with the homeobox and a putative activating domain completely conserved. Comparisons of the promoter sequence and pattern of expression of the gene during development suggest that the regulation of zen has been conserved during evolution. The conservation of zen expression in a subpopulation of the polar cells indicates the existence of an important role in such cells. We describe a transitory segmented pattern of expression of zen in …
ZFWD: a novel subfamily of plant proteins containing a C3H zinc finger and seven WD40 repeats
2000
We describe a new subfamily of WD repeat proteins characterised by the presence of a C3H zinc finger at the N-terminal part of the protein associated with seven WD40 repeats. We have identified four members of this subfamily in Arabidopsis thaliana, one of them with associated expressed sequence tags (ESTs). We have also identified homologous ESTs in rice, cotton, maize, poplar, pine tree and the ice plant. We do not observe animal homologues, suggesting that this subfamily could be specific for plants. Our data suggest an important role for these proteins. Based on the high sequence conservation within the conserved domains, we suggest that these proteins could have a regulatory function.
P sequences ofDrosophilla Subobscuralack exon 3 and may encode a 66 kd repressor-like protein
1991
Abstract Several P homologous sequences have been cloned and sequenced from Drosophila subobscura. These sequences are located at the 85DE region of the O chromosome and at least three of them are organized in tandem. We have identified four copies which exhibit strong similarity between them. All of the isolated elements are truncated at the 5' and 3' ends. They have lost the inverted terminal repeats and exon 3, but maintain exons 0, 1 and 2. They are transcribed producing a polyadenylated RNA. The structure of these transcripts suggests that they are able to encode a 66 kd repressor-like protein, but not a functional transposase. We ask about the biological role of a potential repressor …
Myotonic dystrophy: candidate small molecule therapeutics
2017
Myotonic dystrophy type 1 (DM1) is a rare multisystemic neuromuscular disorder caused by expansion of CTG trinucleotide repeats in the noncoding region of the DMPK gene. Mutant DMPK transcripts are toxic and alter gene expression at several levels. Chiefly, the secondary structure formed by CUGs has a strong propensity to capture and retain proteins, like those of the muscleblind-like (MBNL) family. Sequestered MBNL proteins cannot then fulfill their normal functions. Many therapeutic approaches have been explored to reverse these pathological consequences. Here, we review the myriad of small molecules that have been proposed for DM1, including examples obtained from computational rational …
Progress in Arabidopsis genome sequencing and functional genomics
2000
Arabidopsis thaliana has a relatively small genome of approximately 130 Mb containing about 10% repetitive DNA. Genome sequencing studies reveal a gene-rich genome, predicted to contain approximately 25 000 genes spaced on average every 4.5 kb. Between 10 to 20% of the predicted genes occur as clusters of related genes, indicating that local sequence duplication and subsequent divergence generates a significant proportion of gene families. In addition to gene families, repetitive sequences comprise individual and small clusters of two to three retroelements and other classes of smaller repeats. The clustering of highly repetitive elements is a striking feature of the A. thaliana genome emer…
Design of novel small molecule base-pair recognizers of toxic CUG RNA transcripts characteristics of DM1.
2020
Graphical abstract
In vivo strategies for drug discovery in myotonic dystrophy disorders.
2013
Myotonic dystrophy (DM) is a complex neuromuscular genetic disease for which there is currently no valid therapy. The recent development of non-mammal animal models opened up the possibility of performing drug discovery in vivo, using as screening readout phenotypes with underlying molecular parallels to the disease. In this review we discuss the state of the art technologies already used in large scale drug screening and provide guidance for further development of novel technologies.
Preclinical characterization of antagomiR-218 as a potential treatment for myotonic dystrophy
2021
Myotonic dystrophy type 1 (DM1) is a rare neuromuscular disease caused by expansion of unstable CTG repeats in a non-coding region of the DMPK gene. CUG expansions in mutant DMPK transcripts sequester MBNL1 proteins in ribonuclear foci. Depletion of this protein is a primary contributor to disease symptoms such as muscle weakness and atrophy and myotonia, yet upregulation of endogenous MBNL1 levels may compensate for this sequestration. Having previously demonstrated that antisense oligonucleotides against miR-218 boost MBNL1 expression and rescue phenotypes in disease models, here we provide preclinical characterization of an antagomiR-218 molecule using the HSALR mouse model and patient-d…
Therapeutic Potential of AntagomiR-23b for Treating Myotonic Dystrophy
2020
Myotonic dystrophy type 1 (DM1) is a chronically debilitating, rare genetic disease that originates from an expansion of a noncoding CTG repeat in the dystrophia myotonica protein kinase (DMPK) gene. The expansion becomes pathogenic when DMPK transcripts contain 50 or more repetitions due to the sequestration of the muscleblind-like (MBNL) family of proteins. Depletion of MBNLs causes alterations in splicing patterns in transcripts that contribute to clinical symptoms such as myotonia and muscle weakness and wasting. We previously found that microRNA (miR)-23b directly regulates MBNL1 in DM1 myoblasts and mice and that antisense technology (“antagomiRs”) blocking this microRNA (miRNA) boost…
In situ localization of the Antennapedia gene on the chromosomes of nine Drosophila species of the obscura group.
2008
The homeotic Antennapedia gene, cloned from the genomic DNA of D. subobscura, was localized on the polytene chromosomes of nine species of the Drosophila obscura group. In all of them, the probe used hybridized on chromosomes equivalent to the E element of Muller's terminology. These results are consistent with the idea that single copy genes do not move around the genome and that chromosomal elements have conserved their genetic identity during evolution.
Structural and evolutionary analysis of the copia-like elements in the Arabidopsis thaliana genome.
2001
The analysis of 460 kb of genomic sequence of Arabidopsis thaliana chromosome III allowed us to identify two new transposable elements named AtC1 and AtC2. AtC1 shows identical long terminal repeats (LTRs) and all the structural features characteristic of the copia-like active elements. AtC2 is also a full copia-like element, but a putative stop codon in the open reading frame (ORF) would produce a truncated protein. In order to identify the copia-like fraction of the A. thaliana genome, a careful computer-based analysis of the available sequences (which correspond to 92% of the genome) was performed. Approximately 300 nonredundant copia-like sequences homologous to AtC1 and AtC2 were detec…
Molecular characterization and evolution of the protein phosphatase 2A B' regulatory subunit family in plants.
2002
Abstract Type 2A serine/threonine protein phosphatases (PP2A) are important components in the reversible protein phosphorylation events in plants and other organisms. PP2A proteins are oligomeric complexes constituted by a catalytic subunit and several regulatory subunits that modulate the activity of these phosphatases. The analysis of the complete genome of Arabidopsis allowed us to characterize four novel genes, AtB′ε, AtB′ζ,AtB′η, and AtB′θ, belonging to the PP2A B′ regulatory subunit family. Because four genes of this type had been described previously, this family is composed of eight members. Reverse transcriptase-polymerase chain reaction experiments showed thatAtB′ε mRNAs are prese…
miR-23b and miR-218 silencing increase Muscleblind-like expression and alleviate myotonic dystrophy phenotypes in mammalian models
2018
Functional depletion of the alternative splicing factors Muscleblind-like (MBNL 1 and 2) is at the basis of the neuromuscular disease myotonic dystrophy type 1 (DM1). We previously showed the efficacy of miRNA downregulation in Drosophila DM1 model. Here, we screen for miRNAs that regulate MBNL1 and MBNL2 in HeLa cells. We thus identify miR-23b and miR-218, and confirm that they downregulate MBNL proteins in this cell line. Antagonists of miR-23b and miR-218 miRNAs enhance MBNL protein levels and rescue pathogenic missplicing events in DM1 myoblasts. Systemic delivery of these “antagomiRs” similarly boost MBNL expression and improve DM1-like phenotypes, including splicing alterations, histo…
Statistical Validation of the Identification of Tuna Species: Bootstrap Analysis of Mitochondrial DNA Sequences
2002
Sequencing of the mitochondrial cytochrome b gene has been used to differentiate three tuna species: Thunnus albacares (yellowfin tuna), Thunnus obesus (bigeye tuna), and Katsuwonus pelamis (skipjack). A PCR amplified 528 bp fragment from 30 frozen samples and a 171 bp fragment from 26 canned samples of the three species were analyzed to determine the intraspecific variation and the positions with diagnostic value. Polymorphic sites between the species that did not present intraspecific variation were given a diagnostic value. The genetic distance between the sequences was calculated, and a phylogenetic tree was constructed, showing that the sequences belonging to the same species clustered…
Enforcing Conceptual Modeling to improve the understanding of human genome
2010
It is widely accepted that the use of Conceptual Modeling techniques in modern Software Engineering leads to a more accurate description of the problem domain. The application of these techniques in the context of challenging domains as the human genome is a fascinating task. The relevant biological concepts should be properly addressed through the creation of the corresponding conceptual schema. This schema will improve the description of the global process followed from a DNA sequence to a fully functional protein. Once the conceptual model is established, the corresponding database is created. The database is intended to act as a unified repository of integrated information that will all…
Nemo regulates cell dynamics and represses the expression of miple, a midkine/pleiotrophin cytokine, during ommatidial rotation
2013
AbstractOmmatidial rotation is one of the most important events for correct patterning of the Drosophila eye. Although several signaling pathways are involved in this process, few genes have been shown to specifically affect it. One of them is nemo (nmo), which encodes a MAP-like protein kinase that regulates the rate of rotation throughout the entire process, and serves as a link between core planar cell polarity (PCP) factors and the E-cadherin–β-catenin complex. To determine more precisely the role of nmo in ommatidial rotation, live-imaging analyses in nmo mutant and wild-type early pupal eye discs were performed. We demonstrate that ommatidial rotation is not a continuous process, and …
Myotonic dystrophy associated expanded CUG repeat muscleblind positive ribonuclear foci are not toxic to Drosophila
2005
Myotonic dystrophy type 1 is an autosomal dominant disorder associated with the expansion of a CTG repeat in the 3 0 untranslated region (UTR) of the DMPK gene. Recent data suggest that pathogenesis is predominantly mediated by a gain of function of the mutant transcript. In patients, these expanded CUG repeat-containing transcripts are sequestered into ribonuclear foci that also contain the muscleblind-like proteins. To provide further insights into muscleblind function and the pathogenesis of myotonic dystrophy, we generated Drosophila incorporating CTG repeats in the 3 0 -UTR of a reporter gene. As in patients, expanded CUG repeats form discrete ribonuclear foci in Drosophila muscle cell…
Sequence and analysis of chromosome 4 of the plant Arabidopsis thaliana
1999
The higher plant Arabidopsis thaliana (Arabidopsis) is an important model for identifying plant genes and determining their function. To assist biological investigations and to define chromosome structure, a coordinated effort to sequence the Arabidopsis genome was initiated in late 1996. Here we report one of the first milestones of this project, the sequence of chromosome 4. Analysis of 17.38 megabases of unique sequence, representing about 17% of the genome, reveals 3,744 protein coding genes, 81 transfer RNAs and numerous repeat elements. Heterochromatic regions surrounding the putative centromere, which has not yet been completely sequenced, are characterized by an increased frequency …
Expanded CTG repeats trigger miRNA alterations in Drosophila that are conserved in myotonic dystrophy type 1 patients
2013
Myotonic dystrophy type 1 (DM1) is caused by the expansion of CTG repeats in the 3' untranslated region of the DMPK gene. Several missplicing events and transcriptional alterations have been described in DM1 patients. A large number of these defects have been reproduced in animal models expressing CTG repeats alone. Recent studies have also reported miRNA dysregulation in DM1 patients. In this work, a Drosophila model was used to investigate miRNA transcriptome alterations in the muscle, specifically triggered by CTG expansions. Twenty miRNAs were differentially expressed in CTG-expressing flies. Of these, 19 were down-regulated, whereas 1 was up-regulated. This trend was confirmed for thos…
Generation of GAL4-responsive muscleblind constructs
2002
The muscleblind (mbl) gene encodes protein isoforms Mbl A to Mbl D, which arise by alternative splicing from a common primary transcript. Mbl A, B, and C contain two Zn-finger domains of the type Cys3His, while Mbl D contains only one complete Zn finger. Loss of function mutations in the gene reveal that mbl is involved in both terminal photoreceptor and muscle differentiation in Drosophila. During retina development mbl is essential for rhabdomere differentiation in photoreceptor neuron. Clones homozygous null for mbl completely lack these lightharvesting structures (Begemann et al., 1997). Similarly, the terminal differentiation of the larval body wall muscles is compromised in mbl mutant…
Stage, tissue, and cell specific distribution of alternative Ultrabithorax mRNAs and protein isoforms in the Drosophila embryo
1996
The homeotic gene Ultrabithorax encodes a family of six homeoproteins translated from alternatively spliced mRNAs. The structures of these UBX isoforms have been conserved among anciently diverged Drosoph-ila species and functional distinctions between some isoforms have been reported that suggest subtle but important roles in Ubx action. We present a detailed analysis of the expression patterns of Ubx mRNAs and proteins during embryogenesis, using isoform-specific monoclonal antibodies and synthetic oligonucleotide probes. These patterns are remarkably complex, each mRNA and corresponding protein isoform being expressed in a partially overlapping but distinct stage and tissue-specific patt…