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1.
PLoS One ; 18(7): e0288637, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37494366

RESUMEN

This study focuses on the changes in diet and mobility of people buried in the La Sassa cave (Latium, Central Italy) during the Copper and Bronze Ages to contribute to the understanding of the complex contemporary population dynamics in Central Italy. To that purpose, carbon and nitrogen stable isotope analyses, strontium isotope analyses, and FT-IR evaluations were performed on human and faunal remains from this cave. The stable isotope analyses evidence a slight shift in diet between Copper and Bronze Age individuals, which becomes prominent in an individual, dating from a late phase, when the cave was mainly used as a cultic shelter. This diachronic study documents an increased dietary variability due to the introduction of novel resources in these protohistoric societies, possibly related to the southward spread of northern human groups into Central Italy. This contact between different cultures is also testified by the pottery typology found in the cave. The latter shows an increase in cultural intermingling starting during the beginning of the middle Bronze Age. The local mobility during this phase likely involved multiple communities scattered throughout an area of a few kilometers around the cave, which used the latter as a burial site both in the Copper and Bronze ages.


Asunto(s)
Dieta , Isótopos de Estroncio , Humanos , Espectroscopía Infrarroja por Transformada de Fourier , Italia , Isótopos de Estroncio/análisis , Isótopos de Nitrógeno/análisis , Dinámica Poblacional , Arqueología
2.
Sci Rep ; 6: 32245, 2016 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-27558276

RESUMEN

Calderas are collapse structures related to the emptying of magmatic reservoirs, often associated with large eruptions from long-lived magmatic systems. Understanding how magma is transferred from a magma reservoir to the surface before eruptions is a major challenge. Here we exploit the historical, archaeological and geological record of Campi Flegrei caldera to estimate the surface deformation preceding the Monte Nuovo eruption and investigate the shallow magma transfer. Our data suggest a progressive magma accumulation from ~1251 to 1536 in a 4.6 ± 0.9 km deep source below the caldera centre, and its transfer, between 1536 and 1538, to a 3.8 ± 0.6 km deep magmatic source ~4 km NW of the caldera centre, below Monte Nuovo; this peripheral source fed the eruption through a shallower source, 0.4 ± 0.3 km deep. This is the first reconstruction of pre-eruptive magma transfer at Campi Flegrei and corroborates the existence of a stationary oblate source, below the caldera centre, that has been feeding lateral eruptions for the last ~5 ka. Our results suggest: 1) repeated emplacement of magma through intrusions below the caldera centre; 2) occasional lateral transfer of magma feeding non-central eruptions within the caldera. Comparison with historical unrest at calderas worldwide suggests that this behavior is common.

3.
Gene ; 440(1-2): 16-22, 2009 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-19348876

RESUMEN

The full-length cDNA and the corresponding gene of the heat shock protein 90, Mt-Hsp90, were isolated and characterized in the plant parasitic nematode Meloidogyne artiellia. The full-length Mt-Hsp90 cDNA contained a 5' untranslated region (UTR) of 45 bp with the 22 bp trans-spliced leader SL1, an ORF of 2172 bp encoding a polypeptide of 723 amino acids and a 3' UTR of 191 bp. The deduced amino acid sequence of Mt-hsp90 showed high similarity with other known Hsp90s. Five conserved amino acid signatures indicated that Mt-hsp90 is a cytosolic member of the Hsp90 family. The gene consists of 10 exons and 9 introns, a more expanded gene structure compared to the corresponding Caenorhabditis elegans gene, daf-21. Mt-hsp90 gene was constitutively expressed at high levels in all developmental stages of M. artiellia. Egg masses and second stage juveniles (J2s) were exposed at 5 degrees and 30 degrees C for different periods of times in order to explore the impact of adverse temperature on Mt-hsp90 gene expression. Expression levels of Mt-hsp90 were examined by fluorescent real-time PCR. At 30 degrees C a burst of expression for Mt-hsp90 was observed in J2s after 2 h of heat shock treatment, then expression dropped with longer exposing times, although remaining still relatively high after 24 h. This temperature did not affect Mt-hsp90 gene expression in the egg masses. However, egg masses exposed at 5 degrees C showed a little but gradual increase in the mRNA level with time. By contrast, no significant changes in the Mt-hsp90 level were observed in J2s exposed to cold. These data show that egg masses and J2s exposed to cold and heat stresses have different expression profiles suggesting that Mt-Hsp90 may provide a link between environmental conditions and the life cycle of the nematode.


Asunto(s)
Proteínas HSP90 de Choque Térmico/genética , Proteínas del Helminto/genética , Temperatura , Tylenchoidea/crecimiento & desarrollo , Tylenchoidea/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , ADN Complementario/metabolismo , Regulación del Desarrollo de la Expresión Génica , Genes de Helminto , Intrones , Datos de Secuencia Molecular , Tylenchoidea/genética
4.
Int J Parasitol ; 38(5): 609-15, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17950293

RESUMEN

Animals and plants both respond rapidly to pathogens by inducing the expression of defence-related genes. Within this context, a prominent role has been assigned to the lysozyme. In the present study we isolated and carried out detailed analysis of the lysozyme gene in the plant nematode Meloidogyne artiellia. The expression of lysozyme was up-regulated following exposure of M. artiellia juveniles to the Gram-negative bacterium Serratia marcescens. On the other hand, when isolated eggs containing embryos at various developmental stages were challenged with bacteria, no increase in lysozyme expression was detected. Evidence of lysozyme expression regulation was obtained in the case of adult male and females worms collected from soil. The lysozyme gene was expressed solely in the nematode intestine and, as it is predicted to be secreted, may protect the nematode from microbial infections originating in the intestinal lumen or in the pseudocoelom. This paper demonstrates, to our knowledge for the first time, the immune response to infection in a plant parasitic nematode.


Asunto(s)
Muramidasa/metabolismo , Infecciones por Serratia/inmunología , Serratia marcescens , Tylenchoidea/enzimología , Secuencia de Aminoácidos , Animales , Femenino , Regulación Enzimológica de la Expresión Génica , Inmunidad Innata , Intestinos/enzimología , Intestinos/inmunología , Masculino , Datos de Secuencia Molecular , Muramidasa/genética , Plantas/parasitología , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Infecciones por Serratia/enzimología , Tylenchoidea/genética , Tylenchoidea/inmunología , Regulación hacia Arriba
5.
Mol Biochem Parasitol ; 149(1): 38-47, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16737746

RESUMEN

The Ras-MAPK signal transduction pathway controls multiple developmental events and is involved in the processing of olfactory information in the free living nematode Caenorhabditis elegans. We have studied the Ras-MAPK pathway in the plant parasitic nematode Meloidogyne artiellia. The genes Mt-let-60, Mt-lin-45, Mt-mek-2 and Mt-mpk-1 have been isolated and sequenced. Each of them shows a high level of sequence similarity to its presumed ortholog in C. elegans and key functional domains are structurally conserved. Furthermore, we show that the M. artiellia recombinant MEK-2 protein can phosphorylate and activate the M. artiellia recombinant MPK-1 and the recombinant MEK-2 itself can be phosphorylated and activated by immunoprecipitated mammalian Raf. Surprisingly, the Mt-lin-45 message is not detectable in freshly emerged juveniles or in male specimens, suggesting that it may be quickly degraded in these life stages.


Asunto(s)
Cicer/parasitología , Proteínas del Helminto/genética , Tylenchoidea/genética , Quinasas raf/genética , Secuencia de Aminoácidos , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Femenino , Regulación del Desarrollo de la Expresión Génica , Proteínas del Helminto/química , Proteínas del Helminto/aislamiento & purificación , Proteínas del Helminto/metabolismo , MAP Quinasa Quinasa 2/química , MAP Quinasa Quinasa 2/genética , MAP Quinasa Quinasa 2/aislamiento & purificación , MAP Quinasa Quinasa 2/metabolismo , Masculino , Proteínas Quinasas Activadas por Mitógenos/química , Proteínas Quinasas Activadas por Mitógenos/genética , Proteínas Quinasas Activadas por Mitógenos/aislamiento & purificación , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Datos de Secuencia Molecular , Vías Olfatorias , Fosforilación , Alineación de Secuencia , Transducción de Señal , Tylenchoidea/crecimiento & desarrollo , Tylenchoidea/metabolismo , Quinasas raf/química , Quinasas raf/aislamiento & purificación , Quinasas raf/metabolismo , Proteínas ras/genética , Proteínas ras/metabolismo
6.
Gene ; 349: 87-95, 2005 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-15777697

RESUMEN

A single chitin synthase gene is responsible for chitin production in the eggshells of the plant parasitic nematode Meloidogyne artiellia. In this paper we describe a functional analysis of this gene using RNAi as well as further analysis of two similar genes from the free-living nematode Caenorhabditis elegans. The parasitic life-style of M. artiellia required the development of a novel method for delivery of dsRNA to nematode eggs that may be of utility in other experimental systems. C. elegans chitin synthase genes were silenced by feeding nematodes bacteria expressing appropriate chitin synthase dsRNA from a plasmid vector, while M. artiellia egg masses were soaked in dsRNA solution. The results obtained demonstrated that the synthesis of chitin continues to take place in nematode eggs within the egg sac in the parasitic nematode, and that the removal of this activity affects egg development in both C. elegans and M. artiellia. The method described here provides a new way of investigating gene function in plant parasitic nematodes allowing the validity of potential target genes for novel control methods to be assessed. Furthermore, since intact egg cells within the gelatinous matrix of M. artiellia are permeable to dsRNA, eggs of other nematodes may also be similarly permeable to dsRNA and therefore amenable to use with dsRNAi.


Asunto(s)
Quitina Sintasa/metabolismo , Nematodos/parasitología , Plantas/parasitología , Interferencia de ARN , Tylenchoidea/genética , Animales , Caenorhabditis elegans/genética , Quitina/biosíntesis , Quitina Sintasa/análisis , Quitina Sintasa/genética , Femenino , Genes de Helminto , Estadios del Ciclo de Vida , Nematodos/fisiología , Óvulo/efectos de los fármacos , Óvulo/metabolismo , ARN Bicatenario/farmacología , ARN de Helminto/genética , ARN de Helminto/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Soluciones , Tylenchoidea/enzimología , Tylenchoidea/crecimiento & desarrollo
7.
Phytopathology ; 93(12): 1513-23, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18943615

RESUMEN

ABSTRACT In the Mediterranean Basin, Fusarium oxysporum f. sp. ciceris and the root-knot nematode Meloidogyne artiellia coinfect chickpea. The influence of root infection (after inoculation with 20 nematode eggs and second-stage juveniles per gram of soil) by two M. artiellia populations, from Italy and Syria, on the reaction of chickpea lines and cultivars with partial resistance to Fusarium wilt (CA 252.10.1.OM, CA 255.2.5.0, CPS 1, and PV 61) and with complete resistance to F. oxysporum f. sp. ciceris race 5 (CA 334.20.4, CA 336.14.3.0, ICC 14216 K, and UC 27) was investigated under controlled conditions. In genotypes with partial resistance, infection by M. artiellia significantly increased the severity of Fusarium wilt, irrespective of the fungal inoculum density (3,000 or 30,000 chlamydospores per gram of soil), except in cultivar CPS 1 at the lower fungal inoculum density. In genotypes with complete resistance to Fusarium wilt, infection by M. artiellia overcame the resistance to F. oxysporum f. sp. ciceris race 5 in CA 334.20.4 and CA 336.14.3.0 but not in ICC 14216 K, irrespective of the fungal inoculum density, and overcame the resistance in UC 27 only at the higher inoculum density. Infection by the nematode significantly increased the number of propagules of F. oxysporum f. sp. ciceris race 5 in root tissues of genotypes with complete resistance to Fusarium wilt, compared with roots that were not inoculated with the nematode, irrespective of the fungal inoculum density, except in ICC 14216 K, in which this effect occurred only at the higher inoculum density. Reproduction of an M. artiellia population from Syria in the absence of F. oxysporum f. sp. ciceris race 5 was significantly higher than that of a population from Italy in all tested chick-pea genotypes except ICC 14216 K. However, there was no significant difference between the reproduction rates of the two nematode populations in plants infected with F. oxysporum f. sp. ciceris race 5, irrespective of the fungal inoculum density and the reaction of the genotypes to the fungus.

8.
Gene ; 293(1-2): 191-8, 2002 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-12137957

RESUMEN

Microsatellites have become one of the most powerful genetic markers in biology. We have used DNA sequencing to characterize a highly variable microsatellite (GAAA) locus in the root-knot nematode Meloidogyne artiellia. The use of microsatellite flanking primers produced four amplification products that are defined as electromorphs, based on conventional length criteria. The sequencing of these four amplification products revealed the presence of new variants in the population due to sequence variability. The sum of electromorphs and sequence polymorphisms resulted in a total of six variants. The high degree of variability in the microsatellite containing region is due not only to variation in the number of tetranucleotide repeats but also to variation (length and site variation) in the flanking regions of the microsatellite. These investigations show that, in spite of the size homoplasy, the variability of the microsatellite flanking sequences of M. artiellia could be used as informative markers for phylogenetic reconstructions.


Asunto(s)
Repeticiones de Microsatélite/genética , Tylenchoidea/genética , Alelos , Animales , Secuencia de Bases , ADN de Helmintos/química , ADN de Helmintos/genética , Datos de Secuencia Molecular , Plantas/parasitología , Polimorfismo Genético , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico
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