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1.
Int J Mol Sci ; 25(2)2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38255930

RESUMEN

We comprehensively evaluated the expression of therapeutically targetable immune checkpoint molecules involved in celiac disease (CD). We have focused on the alteration of the CD200/CD200R pathway and Elafin expression in celiac disease and discussed their roles in regulating the immune response. There are limited data related to the expression or function of these molecules in celiac disease. This finding could significantly contribute to the understanding of the clinical manifestation of CD. CD200, CD200R and Elafin distributions were determined by ELISA and immunohistochemistry analyses in serum and biopsies of CD patients. Analyses of Th1 and Th17 cytokines were determined. PCR amplification of a fragment of the PI3 gene was carried out using genomic DNA isolated from whole blood samples of the study subjects. Different aliquots of the PCR reaction product were subjected to RFLP analysis for SNP genotyping and detection. We characterized the expression and function of the CD200-CD200R axis and PI3 in celiac disease. A significantly higher level of soluble CD200 and CD200R and lower expression of PI3 in serum of CD patients was observed compared to healthy controls. Consistent with our results, CD200 expression is regulated by IFN-gamma. Interaction of CD200/CD200R leads to production of type-Th1 and -Th17 cytokines. Regarding the PI3 genotype, the CT genotype proportion SNP rs1733103 and the GG genotype SNP rs41282752 were predominant in CD patients. SNP rs1733103 showed a significant association between the SNP variables and CD. In celiac disease the immune checkpoint is compromised or dysregulated, which can contribute to inflammation and the autoimmunity process. The study of these checkpoint points will lead to the development of targeted therapies aimed at restoring immunological balance in CD. Specific coding regions of the PI3 gene-splice variants predispose the Elafin protein, both at the transcriptional and post-translational levels, to modify its expression and function, resulting in reduced differential functional protein levels in patients with active celiac disease.


Asunto(s)
Enfermedad Celíaca , Proteínas de Punto de Control Inmunitario , Humanos , Elafina , Enfermedad Celíaca/genética , Genotipo , Citocinas/genética
2.
Insect Mol Biol ; 32(6): 725-737, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37615351

RESUMEN

Satellite DNAs (satDNAs) are highly repeated tandem sequences primarily located in heterochromatin, although their occurrence in euchromatin has been reported. Here, our aim was to advance the understanding of satDNA and multiple sex chromosome evolution in heteropterans. We combined cytogenetic and genomic approaches to study, for the first time, the satDNA composition of the genome in an Oxycarenidae bug, Oxycarenus hyalinipennis. The species exhibits a male karyotype of 2n = 19 (14A + 2 m + X1 X2 Y), with a highly differentiated Y chromosome, as demonstrated by C-banding and comparative genomic hybridization, revealing an enrichment of repeats from the male genome. Additionally, comparative analysis between males and females revealed that the 26 identified satDNA families are significantly biased towards male genome, accumulating in discrete regions in the Y chromosome. Exceptionally, the OhyaSat04-125 family was found to be distributed virtually throughout the entire extension of the Y chromosome. This suggests an important role of satDNA in Y chromosome differentiation, in comparison of other repeats, which collectively shows similar abundance between sexes, about 50%. Furthermore, chromosomal mapping of all satDNA families revealed an unexpected high spread in euchromatic regions, covering the entire extension, irrespective of their abundance. Only discrete regions of heterochromatin on the Y chromosome and of the m-chromosomes (peculiar chromosomes commonly observed in heteropterans) were enriched with satDNAs. The putative causes of the intense enrichment of satDNAs in euchromatin are discussed, including the possible existence of burst cycles similar to transposable elements and as a result of holocentricity. These data challenge the classical notion that euchromatin is not enriched with satDNAs.


Asunto(s)
ADN Satélite , Hemípteros , Humanos , Femenino , Masculino , Animales , Eucromatina , Hemípteros/genética , Heterocromatina , Hibridación Genómica Comparativa , Hibridación Fluorescente in Situ , Cromosomas Sexuales , Evolución Molecular
3.
Mem Inst Oswaldo Cruz ; 116: e210259, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35137904

RESUMEN

BACKGROUND: Panstrongylus rufotuberculatus (Hemiptera-Reduviidae) is a triatomine species with a wide geographic distribution and a broad phenotypic variability. In some countries, this species is found infesting and colonising domiciliary ecotopes representing an epidemiological risk factor as a vector of Trypanosoma cruzi, etiological agent of Chagas disease. In spite of this, little is known about P. rufotuberculatus genetic diversity. METHODS: Cytogenetic studies and DNA sequence analyses of one nuclear (ITS-2) and two mitochondrial DNA sequences (cyt b and coI) were carried out in P. rufotuberculatus individuals collected in Bolivia, Colombia, Ecuador and Mexico. Moreover, a geometric morphometrics study was applied to Bolivian, Colombian, Ecuadorian and French Guiana samples. OBJECTIVES: To explore the genetic and phenetic diversity of P. rufotuberculatus from different countries, combining chromosomal studies, DNA sequence analyses and geometric morphometric comparisons. FINDINGS: We found two chromosomal groups differentiated by the number of X chromosomes and the chromosomal position of the ribosomal DNA clusters. In concordance, two main morphometric profiles were detected, clearly separating the Bolivian sample from the other ones. Phylogenetic DNA analyses showed that both chromosomal groups were closely related to each other and clearly separated from the remaining Panstrongylus species. High nucleotide divergence of cyt b and coI fragments were observed among P. rufotuberculatus samples from Bolivia, Colombia, Ecuador and Mexico (Kimura 2-parameter distances higher than 9%). MAIN CONCLUSIONS: Chromosomal and molecular analyses supported that the two chromosomal groups could represent different closely related species. We propose that Bolivian individuals constitute a new Panstrongylus species, being necessary a detailed morphological study for its formal description. The clear morphometric discrimination based on the wing venation pattern suggests such morphological description might be conclusive.


Asunto(s)
Enfermedad de Chagas , Heterópteros , Panstrongylus , Triatoma , Animales , Humanos , Insectos Vectores/genética , Panstrongylus/genética , Filogenia
4.
Int J Mol Sci ; 22(11)2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-34205189

RESUMEN

The triatomine Rhodnius prolixus is the main vector of Chagas disease in countries such as Colombia and Venezuela, and the first kissing bug whose genome has been sequenced and assembled. In the repetitive genome fraction (repeatome) of this species, the transposable elements represented 19% of R. prolixus genome, being mostly DNA transposon (Class II elements). However, scarce information has been published regarding another important repeated DNA fraction, the satellite DNA (satDNA), or satellitome. Here, we offer, for the first time, extended data about satellite DNA families in the R. prolixus genome using bioinformatics pipeline based on low-coverage sequencing data. The satellitome of R. prolixus represents 8% of the total genome and it is composed by 39 satDNA families, including four satDNA families that are shared with Triatoma infestans, as well as telomeric (TTAGG)n and (GATA)n repeats, also present in the T. infestans genome. Only three of them exceed 1% of the genome. Chromosomal hybridization with these satDNA probes showed dispersed signals over the euchromatin of all chromosomes, both in autosomes and sex chromosomes. Moreover, clustering analysis revealed that most abundant satDNA families configured several superclusters, indicating that R. prolixus satellitome is complex and that the four most abundant satDNA families are composed by different subfamilies. Additionally, transcription of satDNA families was analyzed in different tissues, showing that 33 out of 39 satDNA families are transcribed in four different patterns of expression across samples.


Asunto(s)
Enfermedad de Chagas/genética , Elementos Transponibles de ADN/genética , ADN Satélite/genética , Rhodnius/genética , Animales , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/transmisión , Biología Computacional , Humanos , Anotación de Secuencia Molecular , Rhodnius/parasitología , Rhodnius/patogenicidad , Triatoma/genética , Triatoma/parasitología , Secuenciación Completa del Genoma
5.
Mol Biol Rep ; 47(3): 2397-2403, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32034626

RESUMEN

The complete mitogenome sequence of Talpa aquitania, a recently described Talpa species, was assembled using whole-genome sequencing data. It varies in length from 16,776 to 16,846 bp, contains 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, one origin of L-strand replication, and a control region. In the control region, which varied from 1320 to 1390 bp, we identified the extended termination-associated sequence (ETAS-1 and ETAS-2) and the conserved sequence blocks (CSB-1, 2, 3, B, C, D, E, F). In addition, this region includes a 10 bp tandem repeat DNA sequence, with a variable number of repeats that suggest the existence of heteroplasmy. Phylogeny reconstructions based on Maximum Likelihood, Neighbor-joining and Bayesian inference analyses yielded phylogenies with similar topologies demonstrating that T. aquitania and T. occidentalis are sister species.


Asunto(s)
Eulipotyphla/genética , Genoma Mitocondrial , Genómica , Animales , Secuencia de Bases , Biología Computacional/métodos , Eulipotyphla/clasificación , Francia , Genes Mitocondriales , Genómica/métodos , Sistemas de Lectura Abierta , Filogenia , Análisis de Secuencia de ADN , España , Secuenciación Completa del Genoma
6.
Genetica ; 146(4-5): 415-423, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30145730

RESUMEN

The complete mitogenome of Talpa occidentalis, the Iberian mole, was sequenced using a combination of the Illumina and Sanger methods. The 16,962 bp genome obtained contains 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs, and a control region. Thirty-seven identical repetitions of a 10-nucleotide (CACACGTACG) repeat element were identified in the non-coding control region (D-loop). The number, order, and orientation of the mitochondrial genes are the same as in T. europaea, the only mitogenome published so far for this genus. These two mitogenomes differ only at the repeat element included in the control region. The phylogeny obtained for the Talpidae species using the protein-coding genes of these mitogenomes agrees with the current classification of this family.


Asunto(s)
Topos/genética , Animales , Composición de Base/genética , Secuencia de Bases , Especies en Peligro de Extinción , Genes Mitocondriales , Genoma Mitocondrial/genética , Filogenia , Portugal , ARN Ribosómico/genética , ARN de Transferencia/genética , Análisis de Secuencia de ADN/métodos , España
7.
Int J Mol Sci ; 19(5)2018 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-29695139

RESUMEN

Chagas disease or American trypanosomiasis affects six to seven million people worldwide, mostly in Latin America. This disease is transmitted by hematophagous insects known as "kissing bugs" (Hemiptera, Triatominae), with Triatoma infestans and Rhodnius prolixus being the two most important vector species. Despite the fact that both species present the same diploid chromosome number (2n = 22), they have remarkable differences in their total DNA content, chromosome structure and genome organization. Variations in the DNA genome size are expected to be due to differences in the amount of repetitive DNA sequences. The T. infestans genome-wide analysis revealed the existence of 42 satellite DNA families. BLAST searches of these sequences against the R. prolixus genome assembly revealed that only four of these satellite DNA families are shared between both species, suggesting a great differentiation between the Triatoma and Rhodnius genomes. Fluorescence in situ hybridization (FISH) location of these repetitive DNAs in both species showed that they are dispersed on the euchromatic regions of all autosomes and the X chromosome. Regarding the Y chromosome, these common satellite DNAs are absent in T. infestans but they are present in the R. prolixus Y chromosome. These results support a different origin and/or evolution in the Y chromosome of both species.


Asunto(s)
Insectos Vectores/genética , Secuencias Repetitivas de Ácidos Nucleicos , Rhodnius/genética , Triatoma/genética , Animales , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/transmisión , Bandeo Cromosómico , ADN Satélite , Evolución Molecular , Genoma de los Insectos , Genómica/métodos , Hibridación Fluorescente in Situ , Insectos Vectores/parasitología , Rhodnius/parasitología , Triatoma/parasitología , Trypanosoma cruzi
8.
Indian J Med Res ; 144(1): 120-123, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27834335

RESUMEN

BACKGROUND & OBJECTIVES: Insulin regulated aminopeptidase (IRAP) has been related to certain pathologies such as breast cancer, Alzheimer΄s disease and septic shock. IRAP is encoded by the leucyl/cystinyl aminopeptidase (LNPEP) gene. The genetic variation in the LNPEP gene has been analyzed in relation with the mortality and vasopressin clearance in septic shock. The LNPEP rs4869317 SNP (single nucleotide polymorphism) was the most significantly associated SNP with vasopressinase activity, being TT genotype associated with increased mortality. The objective of the present study was to develop a simple method to allow a quick and affordable genotyping for the rs4869317 SNP of LNPEP gene. METHODS: Blood DNA samples were obtained from randomly selected healthy volunteers (n=28). A pair of primers was designed to amplify an 834 bp region of the LNPEP gene containing the rs4869317 SNP. The two alleles (T or A) were detected by digestion of the PCR products with the PacI restriction endonuclease. This enzyme only cuts the PCR products when the adenine is present in the SNP. RESULTS: All individuals showed RFPL (restriction fragment length polymorphism) fragments for the expected genotypes (TT, TA or AA). The methodology was validated by sequencing of the amplified DNAs from several 'T/T' and 'A/A' homozygotes and 'T/A' heterozygotes. The results from both methods showed agreement. INTERPRETATION & CONCLUSIONS: The PCR-RFLP is a simple and reliable method that allows a quick genotyping for the rs4869317 SNP of LNPEP gene. The study of this polymorphism could be useful in future investigations to analyze the role of genetic variants of IRAP in several physiological/pathological conditions.


Asunto(s)
Cistinil Aminopeptidasa/aislamiento & purificación , Genotipo , Polimorfismo de Longitud del Fragmento de Restricción , Choque Séptico/genética , Alelos , Cistinil Aminopeptidasa/genética , Cartilla de ADN , Humanos , Polimorfismo de Nucleótido Simple/genética , Choque Séptico/patología
9.
Naturwissenschaften ; 102(7-8): 44, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26195134

RESUMEN

Three different complete mariner elements were found in the genome of the ant Tapinoma nigerrimum. One (Tnigmar-Mr) was interrupted by a 900-bp insertion that corresponded to an incomplete member of a fourth mariner element, called Azteca. In this work, we isolate and characterize full-length Tnigmar-Az elements in T. nigerrimum. The purpose of this study is to clarify the evolutionary history of Azteca elements and their hosts as well as the possible existence of horizontal transfer processes. For this, Azteca-like elements were also retrieved from the available sequences of various ant genomes, representing four different ant subfamilies: Dolichoderinae, Formicinae, Myrmicinae, and Ponerinae. The tree topology resulting for the Azteca-like elements bore very little resemblance to that of their respective hosts. The pervasive presence of Azteca-like elements in all ant genomes, together with the observation that extant copies are usually younger than the genomes that host them, could be explained either by lineage sorting or by recent horizontal transfer of active elements. However, the finding of closer genetic relationships between elements than between the ants that host them is consistent with the latter scenario. This is clearly observed in Sinvmar-Az, Tnigmar-Az, Acepmar-Az, and Cflomar-Az elements, suggesting the existence of horizontal transfer processes. On the contrary, some elements displayed more divergence than did the hosts harboring them. This may reflect either further horizontal transfer events or random lineage sorting.


Asunto(s)
Hormigas/clasificación , Hormigas/enzimología , Proteínas de Unión al ADN/genética , Filogenia , Transposasas/genética , Animales , Hormigas/genética , Transferencia de Gen Horizontal , Variación Genética , Genoma de los Insectos/genética
10.
Genes (Basel) ; 15(4)2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38674330

RESUMEN

The satellitome of the beetle Chrysolina americana Linneo, 1758 has been characterized through chromosomal analysis, genomic sequencing, and bioinformatics tools. C-banding reveals the presence of constitutive heterochromatin blocks enriched in A+T content, primarily located in pericentromeric regions. Furthermore, a comprehensive satellitome analysis unveils the extensive diversity of satellite DNA families within the genome of C. americana. Using fluorescence in situ hybridization techniques and the innovative CHRISMAPP approach, we precisely map the localization of satDNA families on assembled chromosomes, providing insights into their organization and distribution patterns. Among the 165 identified satDNA families, only three of them exhibit a remarkable amplification and accumulation, forming large blocks predominantly in pericentromeric regions. In contrast, the remaining, less abundant satDNA families are dispersed throughout euchromatic regions, challenging the traditional association of satDNA with heterochromatin. Overall, our findings underscore the complexity of repetitive DNA elements in the genome of C. americana and emphasize the need for further exploration to elucidate their functional significance and evolutionary implications.


Asunto(s)
Escarabajos , ADN Satélite , Eucromatina , Heterocromatina , Animales , Heterocromatina/genética , Escarabajos/genética , ADN Satélite/genética , Eucromatina/genética , Genoma de los Insectos , Hibridación Fluorescente in Situ
11.
Gene ; 899: 148144, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38195050

RESUMEN

Aphids and ants are mutualistic species with a close space-time relationship, which may facilitate the occurrence of horizontal transfer events between these insect groups. Myrmar-like mariner elements were previously isolated from two ant (Myrmica ruginodis and Tapinoma ibericum) and two aphid species (Aphis fabae and Aphis hederae). The aim of this work is to determine the presence of Myrmar-like mariner elements in new ant and aphid species, as well as to analyze the likelihood of horizontal transfer events between these taxa. To accomplish this, the Myrmar-like element has been isolated from five aphid species and six ant species. Among these new analyzed species, full-length Myrmar-like mariner elements with very high sequence similarity have been isolated from the aphids Aphis nerii, Aphis spiraecola, Brachycaudus cardui, and Rhopalosiphum maidis as well as from the ants Lasius grandis and Lasius niger, even though aphids and ants belong to two insect orders (Hemiptera and Hymenoptera) that have evolved independently for at least 300 million-years. Both Lasius species establish frequent mutualistic relationships with multiple aphid species, including A. nerii, A. spiraecola, and B. cardui. The study of the putative protein encoded by them and the phylogenetic analysis suggests that they could be active transposons shared by aphids and ants through horizontal transfer events. Additionally, mariner elements with internal deletion were found in several aphids and one ant species, showing a high degree of sequence similarity among them. The characteristics of these elements with internal deletion suggest a complex origin involving various evolutionary processes, possibly including also horizontal transfer events. Myrmar-like elements have also been isolated from the other ant species, although without similarity with the aphid mariner sequences. Myrmar-like elements are also present in phylogenetically distant insect species, as well as in one crustacean species. The phylogenetic study carried out with all Myrmar-like elements suggests the probable occurrence of horizontal transfer events.


Asunto(s)
Hormigas , Áfidos , Animales , Hormigas/genética , Áfidos/genética , Elementos Transponibles de ADN/genética , Filogenia , Simbiosis/genética
12.
Bull Entomol Res ; 103(5): 538-46, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23448367

RESUMEN

The Colorado potato beetle (Leptinotarsa decemlineata, family Chrysomelidae),a phytophagous insect, which feeds preferably on potatoes, constitutes a serious pest of this crop and causes extensive damage to tomatoes and egg plants. It has a remarkable ability to develop resistance quickly against insecticides and shows a diversified and flexible life history. Consequently, the control of this pest has become difficult, requiring the development of new alternative biotechnology-based strategies. Such strategies require a thorough knowledge of the beetle's genome,including the repetitive DNA. Satellite DNA (stDNA), composed of long arrays of tandemly arranged repeat units, constitutes the major component of heterochromatin and is located mainly in centromeric and telomeric chromosomal regions. We have studied two different unrelated satellite-DNA families of which the consensus sequences were 295 and 109bp in length, named LEDE-I and LEDE-II, respectively.Both were AT-rich (70.8% and 71.6%, respectively). Predictive models of sequence-dependent DNA bending and the study of electrophoretic mobility on non-denaturing polyacrylamide gels have shown that the DNA was curved in both satellite-DNA families. Among other features, the chromosome localization of both stDNAs has been studied. In situ hybridization performed on meiotic and mitoticnuclei showed chromosomes, including the X chromosome, with zero, one, or two stDNAs. In recent years, it has been proposed that the repetitive DNA may play a key role in biological diversification processes. This is the first molecular and cytogenetic study conducted on L. decemlineata repetitive DNA and specifically on stDNA, which is one of the important constituents of eukaryotic genomes.


Asunto(s)
Escarabajos/genética , Genoma de los Insectos , Repeticiones de Microsatélite , Animales , Cromosomas de Insectos , Femenino , Masculino
13.
Insects ; 14(9)2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37754740

RESUMEN

This study focused on analyzing the distribution of microsatellites in holocentric chromosomes of the Triatominae subfamily, insect vectors of Chagas disease. We employed a non-denaturing FISH technique to determine the chromosomal distribution of sixteen microsatellites across twenty-five triatomine species, involving five genera from the two principal tribes: Triatomini and Rhodniini. Three main hybridization patterns were identified: strong signals in specific chromosomal regions, dispersed signals dependent on microsatellite abundance and the absence of signals in certain chromosomal regions or entire chromosomes. Significant variations in hybridization patterns were observed between Rhodniini and Triatomini species. Rhodniini species displayed weak and scattered hybridization signals, indicating a low abundance of microsatellites in their genomes. In contrast, Triatomini species exhibited diverse and abundant hybridization patterns, suggesting that microsatellites are a significant repetitive component in their genomes. One particularly interesting finding was the high abundance of GATA repeats, and to a lesser extent AG repeats, in the Y chromosome of all analyzed Triatomini species. In contrast, the Y chromosome of Rhodniini species did not show enrichment in GATA and AG repeats. This suggests that the richness of GATA repeats on the Y chromosome likely represents an ancestral trait specific to the Triatomini tribe. Furthermore, this information can be used to elucidate the evolutionary relationships between Triatomini and other groups of reduviids, contributing to the understanding of the subfamily's origin. Overall, this study provides a comprehensive understanding of the composition and distribution of microsatellites within Triatominae genomes, shedding light on their significance in the evolutionary processes of these species.

14.
Sci Rep ; 13(1): 534, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36631492

RESUMEN

The W chromosome of Lepidoptera is typically gene-poor, repeat-rich and composed of heterochromatin. Pioneering studies investigating this chromosome reported an abundance of mobile elements. However, the actual composition of the W chromosome varies greatly between species, as repeatedly demonstrated by comparative genomic hybridization (CGH) or fluorescence in situ hybridization (FISH). Here we present an analysis of repeats on the W chromosome in the willow beauty, Peribatodes rhomboidaria (Geometridae), a species in which CGH predicted an abundance of W-enriched or W-specific sequences. Indeed, comparative analysis of male and female genomes using RepeatExplorer identified ten putative W chromosome-enriched repeats, most of which are LTR or LINE mobile elements. We analysed the two most abundant: PRW LINE-like and PRW Bel-Pao. The results of FISH mapping and bioinformatic analysis confirmed their enrichment on the W chromosome, supporting the hypothesis that mobile elements are the driving force of W chromosome differentiation in Lepidoptera. As the W chromosome is highly underrepresented in chromosome-level genome assemblies of Lepidoptera, this recently introduced approach, combining bioinformatic comparative genome analysis with molecular cytogenetics, provides an elegant tool for studying this elusive and rapidly evolving part of the genome.


Asunto(s)
Mariposas Nocturnas , Salix , Animales , Femenino , Masculino , Hibridación Genómica Comparativa , Hibridación Fluorescente in Situ , Mariposas Nocturnas/genética , Retroelementos/genética , Salix/genética , Cromosomas Sexuales/genética
15.
Harmful Algae ; 130: 102543, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38061820

RESUMEN

Dinoflagellates are known to possess an exceptionally large genome organized in permanently condensed chromosomes. Focusing on the contribution of satellite DNA (satDNA) to the whole DNA content of genomes and its potential role in the architecture of the chromosomes, we present the characterization of the satellitome of Alexandriun minutum strain VGO577. To achieve this, we analyzed Illumina reads using graph-based clustering and performed complementary bioinformatic analyses. In this way, we discovered 180 satDNAs occupying 17.38 % of the genome. The 12 most abundant satDNAs represent the half of the satellitome but no satDNA is overrepresented, with the most abundant contributing ∼1.56 % of the genome. The largest repeat unit is 517 bp long but more than the half of the satDNAs (101) have repeat units shorter than 20 bp. We used FISH to map a selected set of 26 satDNAs. Although some satDNAs generate discrete hybridization signals at specific chromosomal locations (hybridization sites, HS), our cytological analysis showed that most satDNAs are dispersed throughout the genome, probably forming short arrays. Two satDNAs co-localize with the 45S rDNA. With the exception of telomeric DNA, no other satDNA yields HS on all chromosomes. In addition, we analyzed nine satDNAs yielding HS in VGO577 in four other A. minutum strains. Polymorphism at the intraspecific level was found for the presence/absence and/or abundance of some satDNAs, suggesting the amplification/deletion of these satDNAs following geographic separation or during culture maintenance of the strains. We also discuss how these results contribute to the understanding of chromosome architecture and evolution of dinoflagellate genomes.


Asunto(s)
Dinoflagelados , Dinoflagelados/genética , ADN Satélite , Análisis de Secuencia de ADN/métodos , ADN Ribosómico
16.
Genes (Basel) ; 14(2)2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36833298

RESUMEN

The genome of Triatoma delpontei Romaña & Abalos 1947 is the largest within Heteroptera, approximately two to three times greater than other evaluated Heteroptera genomes. Here, the repetitive fraction of the genome was determined and compared with its sister species Triatoma infestans Klug 1834, in order to shed light on the karyotypic and genomic evolution of these species. The T. delpontei repeatome analysis showed that the most abundant component in its genome is satellite DNA, which makes up more than half of the genome. The T. delpontei satellitome includes 160 satellite DNA families, most of them also present in T. infestans. In both species, only a few satellite DNA families are overrepresented on the genome. These families are the building blocks of the C-heterochromatic regions. Two of these satellite DNA families that form the heterochromatin are the same in both species. However, there are satellite DNA families highly amplified in the heterochromatin of one species that in the other species are in low abundance and located in the euchromatin. Therefore, the present results depicted the great impact of the satellite DNA sequences in the evolution of Triatominae genomes. Within this scenario, satellitome determination and analysis led to a hypothesis that explains how satDNA sequences have grown on T. delpontei to reach its huge genome size within true bugs.


Asunto(s)
Triatoma , Triatominae , Animales , Triatoma/genética , Triatominae/genética , ADN Satélite , Heterocromatina , Genómica
17.
Naturwissenschaften ; 99(12): 1007-20, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23097152

RESUMEN

To date, only three types of full-length mariner elements have been described in ants, each one in a different genus of the Myrmicinae subfamily: Sinvmar was isolated from various Solenopsis species, Myrmar from Myrmica ruginodis, and Mboumar from Messor bouvieri. In this study, we report the coexistence of three mariner elements (Tnigmar-Si, Tnigmar-Mr, and Tnigmar-Mb) in the genome of a single species, Tapinoma nigerrimum (subfamily Dolichoderinae). Molecular evolutionary analyses of the nucleotide sequence data revealed a general agreement between the evolutionary history of most the elements and the ant species that harbour them, and suggest that they are at the vertical inactivation stage of the so-called Mariner Life Cycle. In contrast, significantly reduced levels of synonymous divergence between Mboumar and Tnigmar-Mb and between Myrmar and Botmar (a mariner element isolated from Bombus terrestris), relative to those observed between their hosts, suggest that these elements arrived to the species that host them by horizontal transfer, long after the species' split. The horizontal transfer events for the two pairs of elements could be roughly dated within the last 2 million years and about 14 million years, respectively. As would be expected under this scenario, the coding sequences of the youngest elements, Tnigmar-Mb and Mboumar, are intact and, thus, potentially functional. Each mariner element has a different chromosomal distribution pattern according to their stage within the Mariner Life Cycle. Finally, a new defective transposable element (Azteca) has also been found inserted into the Tnigmar-Mr sequences showing that the ant genomes have been invaded by at least four different types of mariner elements.


Asunto(s)
Hormigas/genética , Elementos Transponibles de ADN/genética , Genoma/genética , Animales , Hormigas/clasificación , Secuencia de Bases , Cromosomas/genética , Proteínas de Unión al ADN , Variación Genética , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Transposasas
18.
Gut ; 60(7): 915-22, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21317420

RESUMEN

BACKGROUND AND AIMS: Coeliac disease (CD) is triggered by an abnormal reaction to gluten. Peptides resulting from partially digested gluten of wheat, barley or rye cause inflammation of the small intestinal mucosa. Previous contradictory studies suggest that oats may trigger the abnormal immunological response in patients with CD. Monoclonal antibodies (moAbs) against the main immunotoxic 33-mer peptide (A1 and G12) react strongly against wheat, barley and rye but have less reactivity against oats. The stated aim of this study is to test whether this observed reactivity could be related to the potential toxicity of oats for patients with CD. METHODS: In the present study, different oat varieties, controlled for their purity and by their distinct protein pattern, were used to examine differences in moAb G12 recognition by ELISA and western blot. Immunogenicity of oat varieties was determined by 33-mer concentration, T cell proliferation and interferon γ production. RESULTS: Three groups of oat cultivars reacting differently against moAb G12 could be distinguished: a group with considerable affinity, a group showing slight reactivity and a third with no detectable reactivity. The immunogenicity of the three types of oats as well as that of a positive and negative control was determined with isolated peripheral blood mononuclear T cells from patients with CD by measurement of cell proliferation and interferon γ release. A direct correlation of the reactivity with G12 and the immunogenicity of the different prolamins was observed. CONCLUSIONS: The results showed that the reactivity of the moAb G12 is proportional to the potential immunotoxicity of the cereal cultivar. These differences may explain the different clinical responses observed in patients suffering from CD and open up a means to identify immunologically safe oat cultivars, which could be used to enrich a gluten-free diet.


Asunto(s)
Avena/inmunología , Enfermedad Celíaca/inmunología , Adolescente , Anticuerpos Monoclonales/inmunología , Afinidad de Anticuerpos , Diversidad de Anticuerpos/inmunología , Avena/efectos adversos , Avena/química , Avena/clasificación , Enfermedad Celíaca/etiología , Proliferación Celular , Células Cultivadas , Niño , Preescolar , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Glútenes/análisis , Glútenes/inmunología , Humanos , Interferón gamma/biosíntesis , Activación de Linfocitos/inmunología , Masculino , Fragmentos de Péptidos/inmunología , Prolaminas/análisis , Especificidad de la Especie , Linfocitos T/inmunología
19.
Mitochondrial DNA B Resour ; 7(6): 986-988, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35712538

RESUMEN

In this study, we report the complete mitochondrial genome or mitogenome of the blister beetle Hycleus scutellatus, one endemic species from the Iberian Peninsula. The mitogenome was 16,035 base pairs in length, with an A + T content of 71.7%. It has 37 genes including 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. To analyze the evolutionary position of H. scutellatus, we constructed a phylogenetic tree using all available mitogenomes from species of the family Meloidae. The results show that Hycleus species are very close to the genus Mylabris. We present here the mitogenome of H. scutellatus as a new resource to elucidate the phylogenetic relations among the Meloidea family, being this source very useful for future evolutionary analyses of blister beetles.

20.
Genes (Basel) ; 13(8)2022 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-35893062

RESUMEN

The ant Tapinoma ibericum Santschi, 1925 is native to the Iberian Peninsula. This species, as well as other species from the Tapinoma nigerrimum complex, could form supercolonies that make these species potentially invasive and could give rise to pests. Recently a mature colony from this species has been found in the Isle of Wight (United Kingdom). Mitogenomes have been used to study the taxonomy, biogeography and genetics of species, improving the development of strategies against pest invasion. However, the number of available mitogenomes from the subfamily Dolichoderinae is still scarce and only two of these mitogenomes belong to Tapinoma species. Herein, the complete mitogenome of T. ibericum is presented in order to increase the molecular information of the genus. The T. ibericum mitogenome, retrieved by Next-Generation Sequencing data, is 15,715 bp in length. It contains the typical set of 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNAs and the A + T-rich control region. Comparisons of the T. ibericum mitogenome with other dolichoderine mitogenomes revealed the existence of four gene rearrangements in relation with the ancestral insect mitogenome. One of these rearrangements, involving the tRNA-Ile, tRNA-Gln and tRNA-Met genes, was found in most of the analyzed ant mitogenomes. Probably this rearrangement was an ancestral or plesiomorphic character in Formicidae. Interestingly, another rearrangement that affects to tRNA-Trp, tRNA-Cys and tRNA-Tyr genes was found only in Tapinoma species. This change could be a synapomorphic character for the genus Tapinoma, and could be used as a phylogenetic marker. Additionally, a phylogenetic analysis was performed using the protein-coding gene sequences from available Dolichoderinae mitogenomes, as well as mitogenomes from representative species from other Formicidae subfamilies. Results support the monophyletic nature of the genus Tapinoma placing it within the same clade as the rest of Dolichoderinae species.


Asunto(s)
Hormigas , Genoma Mitocondrial , Animales , Hormigas/genética , Secuencia de Bases , Genoma Mitocondrial/genética , Filogenia , ARN de Transferencia/genética
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