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6. Neuromeric distribution of nicotinamide adenine dinucleotide phosphate-diaphorase activity in the adult lamprey brain

Author

Pombal, Manuel A., Megías, Manuel, Lozano Rebollo, Daniel, López Redondo, Jesús María, Pombal, Manuel A., Megías, Manuel, Lozano Rebollo, Daniel, and López Redondo, Jesús María

Abstract

Funding This work was supported by the grant PID2020-113646GA-I00 funded by the Spanish Ministry of Science and Innovation and by “ERDF A way of making Europe” and by a Xunta de Galicia grant (ED431F 2021/06)., This study reports for the first time the distribution and morphological characterization of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d; a reliable marker of nitric oxide synthase activity) positive elements in the central nervous system of the adult river lamprey (Lampetra fluviatilis) on the framework of the neuromeric model and compares their cytoarchitectonic organization with that of gnathostomes. Both NADPH- d exhibiting cells and fibers were observed in all major divisions of the lamprey brain as well as in the spinal cord. In the secondary prosencephalon, NADPH-d positive cells were observed in the mitral cell layer of the olfactory bulb, evaginated pallium, amygdala, dorsal striatum, septum, lateral preoptic nucleus, caudal paraventricular area, posterior entopeduncular nucleus, nucleus of the stria medullaris, hypothalamic periventricular organ and mamillary region sensu lato. In the lamprey diencephalon, NADPH-d labeled cells were observed in several nuclei of the prethalamus, epithalamus, pretectum, and the basal plate. Especially remarkable was the staining observed in the right habenula and several pretectal nuclei. NADPH-d positive cells were also observed in the following mesencephalic areas: optic tectum (two populations), torus semicircularis, nucleus M5 of Schöber, and a ventral tegmental periventricular nucleus. Five different cell populations were observed in the isthmic region, whereas the large sensory dorsal cells, some cells located in the interpeduncular nucleus, the motor nuclei of most cranial nerves, the solitary tract nucleus, some cells of the reticular nuclei, and small cerebrospinal fluid-contacting (CSF-c) cells were the most evident stained cells of the rhombencephalon proper. Finally, several NADPH-d positive cells were observed in the rostral part of the spinal cord, including the large sensory dorsal cells, numerous CSF-c cells, and some dorsal and lateral interneurons. NADPH-d positive fibers were observed, Ministerio de Ciencia e Innovación (MICIN), Xunta de Galicia, Depto. de Biología Celular, Fac. de Ciencias Biológicas, TRUE, pub

Published
2024

30. Acceptance and knowledge of evolutionary theory among third-year university students in Spain

Author

Universidad de Alicante. Departamento de Fisiología, Genética y Microbiología, Gefaell, Juan, Prieto, Tamara, Abdelaziz, Mohamed, Álvarez, Inés, Anton, Josefa, Arroyo, Juan, Bella, Jose L., Botella, Miguel, Bugallo, Anxela, Claramonte, Vicente, Gijón, José, Lizarte, Emilio, Maroto, Rosa M., Megías, Manuel, Milá, Borja, Ramón, Cori, Vila, Marta, Rolán-Alvarez, Emilio, Universidad de Alicante. Departamento de Fisiología, Genética y Microbiología, Gefaell, Juan, Prieto, Tamara, Abdelaziz, Mohamed, Álvarez, Inés, Anton, Josefa, Arroyo, Juan, Bella, Jose L., Botella, Miguel, Bugallo, Anxela, Claramonte, Vicente, Gijón, José, Lizarte, Emilio, Maroto, Rosa M., Megías, Manuel, Milá, Borja, Ramón, Cori, Vila, Marta, and Rolán-Alvarez, Emilio

Abstract

The theory of evolution is one of the greatest scientific achievements in the intellectual history of humankind, yet it is still contentious within certain social groups. Despite being as robust and evidence-based as any other notable scientific theory, some people show a strong reluctance to accept it. In this study, we used the Measure of Acceptance of the Theory of Evolution (MATE) and Knowledge of Evolution Exam (KEE) questionnaires with university students from four academic degree programs (Chemistry, English, History, and Biology) of ten universities from Spain to measure, respectively, acceptance and knowledge of evolutionary theory among third-year undergraduate students (nMATE = 978; nKEE = 981). Results show that acceptance of evolution is relatively high (87.2%), whereas knowledge of the theory is moderate (5.4 out of 10) although there are differences across degrees (Biology>Chemistry>History>English), and even among various universities (ranging from 4.71 to 5.81). Statistical analysis reveals that knowledge of evolutionary theory among Biology students is partially explained by the relative weight of evolutionary themes within the curriculum, suggesting that an increase in the number of hours dedicated to this topic could have a direct influence on students’ knowledge of it. We also found that religion may have a significant—although relatively small—negative influence on evolutionary theory acceptance. The moderate knowledge of evolution in our undergraduate students, together with the potential problem of acceptance in certain groups, suggests the need for a revision of the evolutionary concepts in the teaching curricula of our students since primary school.

Published
2020

34. Acceptance and knowledge of evolutionary theory among third-year university students in Spain

Author

Gefaell, Juan, primary, Prieto, Tamara, additional, Abdelaziz, Mohamed, additional, Álvarez, Inés, additional, Antón, Josefa, additional, Arroyo, Juan, additional, Bella, Jose L., additional, Botella, Miguel, additional, Bugallo, Anxela, additional, Claramonte, Vicente, additional, Gijón, José, additional, Lizarte, Emilio, additional, Maroto, Rosa M., additional, Megías, Manuel, additional, Milá, Borja, additional, Ramón, Cori, additional, Vila, Marta, additional, and Rolán-Alvarez, Emilio, additional

Published
2020
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35. Priming of defense-related genes in Brassica oleraceavar. capitatausing concentrated metabolites produced by Rhizobium tropiciCIAT 899

Author

Santos, Ivonaldo Reis, Ribeiro, Daiane Gonzaga, Távora, Fabiano Touzdjian Pinheiro Kohlrausch, Maximiano, Mariana Rocha, Rabelo, Ana Carolina, Rios, Thuanny Borba, Reis Junior, Fábio Bueno, Megías, Manuel, Silva, Luciano Paulino, and Mehta, Angela

Abstract

To verify the potential of metabolites extracted from Rhizobium tropicito trigger the priming of defense responses in cruciferous plants, we analyzed the expression of defense-related genes by qRT-PCR. Brassica oleraceavar. capitata, susceptible to Xanthomonas campestrispv. campestris, were grown in greenhouse conditions. At 18 days after sowing, plants were inoculated with 1 mL of 1% concentrated metabolites produced by R. tropici(CM-RT) in the root. In a second experiment, leaves were sprayed with 1 mL of a solution containing 1% CM-RT. Aerial and root tissue were collected separately at 0 (non-treated control condition), 24, and 48 h after application, submitted to RNA extraction and gene expression analysis by qRT-PCR. The results showed that, after root treatment with CM-RT, most evaluated genes were upregulated at 24 h after application and downregulated at 48 h after application in roots, while in leaves, genes were downregulated both at 24 and 48 h after application. On the other hand, leaf treatment with CM-RT showed that most evaluated genes in leaves and roots were upregulated at 24 and 48 h after application. These results indicate that the effect of CM-RT applied in roots seems restricted to the applied region and is not sustained, while the application in leaves results in a more systemic response and maintenance of the effect of CM-RT for a longer period. The results obtained in this study emphasize the biotechnological potential of using metabolites of R. tropicias an elicitor of active defense responses in plants.

Published
2022
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38. Selection of Rhizobium Strains for the Common Bean Crop

Author

Hungria, Mariangela, Chueire, Ligia Maria O., Andrade, Diva S., Probanza, Augustin, Guttierrez-Mañero, Francisco J., Mostasso, Lilian, Vargas, Milton A. T., Megías, Manuel, Pedrosa, Fabio O., editor, Hungria, Mariangela, editor, Yates, Geoffrey, editor, and Newton, William E., editor

Published
2000
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41. Genomic basis of broad host range and environmental adaptability of Rhizobium tropici CIAT 899 and Rhizobium sp. PRF 81 which are used in inoculants for common bean (Phaseolus vulgaris L.)

Author

Ormeño-Orrillo Ernesto, Menna Pâmela, Almeida Luiz Gonzaga P, Ollero Francisco Javier, Nicolás Marisa Fabiana, Pains Rodrigues Elisete, Shigueyoshi Nakatani Andre, Silva Batista Jesiane Stefânia, Oliveira Chueire Ligia Maria, Souza Rangel Celso, Ribeiro Vasconcelos Ana Tereza, Megías Manuel, Hungria Mariangela, and Martínez-Romero Esperanza

Subjects
Nodulation, Nitrogen fixation, Plant-microbe interactions, Antimicrobial resistance, Biotechnology, TP248.13-248.65, Genetics, QH426-470
Abstract

Abstract Background Rhizobium tropici CIAT 899 and Rhizobium sp. PRF 81 are α-Proteobacteria that establish nitrogen-fixing symbioses with a range of legume hosts. These strains are broadly used in commercial inoculants for application to common bean (Phaseolus vulgaris) in South America and Africa. Both strains display intrinsic resistance to several abiotic stressful conditions such as low soil pH and high temperatures, which are common in tropical environments, and to several antimicrobials, including pesticides. The genetic determinants of these interesting characteristics remain largely unknown. Results Genome sequencing revealed that CIAT 899 and PRF 81 share a highly-conserved symbiotic plasmid (pSym) that is present also in Rhizobium leucaenae CFN 299, a rhizobium displaying a similar host range. This pSym seems to have arisen by a co-integration event between two replicons. Remarkably, three distinct nodA genes were found in the pSym, a characteristic that may contribute to the broad host range of these rhizobia. Genes for biosynthesis and modulation of plant-hormone levels were also identified in the pSym. Analysis of genes involved in stress response showed that CIAT 899 and PRF 81 are well equipped to cope with low pH, high temperatures and also with oxidative and osmotic stresses. Interestingly, the genomes of CIAT 899 and PRF 81 had large numbers of genes encoding drug-efflux systems, which may explain their high resistance to antimicrobials. Genome analysis also revealed a wide array of traits that may allow these strains to be successful rhizosphere colonizers, including surface polysaccharides, uptake transporters and catabolic enzymes for nutrients, diverse iron-acquisition systems, cell wall-degrading enzymes, type I and IV pili, and novel T1SS and T5SS secreted adhesins. Conclusions Availability of the complete genome sequences of CIAT 899 and PRF 81 may be exploited in further efforts to understand the interaction of tropical rhizobia with common bean and other legume hosts.

Published
2012
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42. Regulation of hsnT, nodF and nodE genes in Rhizobium tropici CIAT 899 and their roles in the synthesis of Nod factors and in the symbiosis

Author

Gomes, Douglas Fabiano, primary, Tullio, Leandro Datola, additional, del Cerro, Pablo, additional, Nakatani, Andre Shigueyoshi, additional, Rolla-Santos, Amanda Alves Paiva, additional, Gil-Serrano, Antonio, additional, Megías, Manuel, additional, Ollero, Francisco Javier, additional, and Hungria, Mariangela, additional

Published
2019
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44. BAC recombineering of the agouti loci from spotted gar and zebrafish reveals the evolutionary ancestry of dorsal-ventral pigment asymmetry in fish

Author

Cal, Laura, Megías, Manuel, Cerdá-Reverter, José Miguel, Postlethwait, John H., Braasch, Ingo, Rotllant, Josep, Ministerio de Economía y Competitividad (España), Alexander von Humboldt Foundation, and Volkswagen Foundation

Subjects
animal structures, Species Specificity, Pigmentation, embryonic structures, Fishes, Agouti Signaling Protein, Animals, sense organs, Pigments, Biological, Genetic Engineering, Biological Evolution, Article, Recombinant Proteins
Abstract

Dorsoventral pigment patterning, characterized by a light ventrum and a dark dorsum, is one of the most widespread chromatic adaptations in vertebrate body coloration. In mammals, this countershading depends on differential expression of agouti‐signaling protein (ASIP), which drives a switch of synthesis of one type of melanin to another within melanocytes. Teleost fish share countershading, but the pattern results from a differential distribution of multiple types of chromatophores, with black–brown melanophores most abundant in the dorsal body and reflective iridophores most abundant in the ventral body. We previously showed that Asip1 (a fish ortholog of mammalian ASIP) plays a role in patterning melanophores. This observation leads to the surprising hypothesis that agouti may control an evolutionarily conserved pigment pattern by regulating different mechanisms in mammals and fish. To test this hypothesis, we compared two ray‐finned fishes: the teleost zebrafish and the nonteleost spotted gar (Lepisosteus oculatus). By examining the endogenous pattern of asip1 expression in gar, we demonstrate a dorsoventral‐graded distribution of asip1 expression that is highest ventrally, similar to teleosts. Additionally, in the first reported experiments to generate zebrafish transgenic lines carrying a bacterial artificial chromosome (BAC) from spotted gar, we show that both transgenic zebrafish lines embryos replicate the endogenous asip1 expression pattern in adult zebrafish, showing that BAC transgenes from both species contain all of the regulatory elements required for regular asip1 expression within adult ray‐finned fishes. These experiments provide evidence that the mechanism leading to an environmentally important pigment pattern was likely in place before the origin of teleosts, Grant sponsor: Spanish Economy and Competitiveness Ministry; Grant numbers: AGL2011-23581 and AGL2014-52473R; Grant sponsor: NIH; Grant num-bers: R01 OD011116 (alias R01 RR020833) and R24 OD01119004; Grant sponsor: Alexander von Humboldt Foundation; Grant sponsor: Volkswagen Foundation Initiative Evolutionary Biology; Grant number: I/84 815.

Published
2017

46. Quorum sensing communication: Bradyrhizobium-Azospirillum interaction via N-acyl-homoserine lactones in the promotion of soybean symbiosis

Author

dos Santos Lima Fagotti, Dáfila, primary, Abrantes, Julia Laura Fernandes, additional, Cerezini, Paula, additional, Fukami, Josiane, additional, Nogueira, Marco A., additional, del Cerro, Pablo, additional, Valderrama-Fernández, Rocio, additional, Ollero, Francisco J., additional, Megías, Manuel, additional, and Hungria, Mariangela, additional

Published
2018
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