Selenium affects genes associated with immunity and apoptosis in in vitro follicles of ewes

Selenium plays an important role in bodily functions. It activates immune cells such as neutrophils and immunity through T cells. However, its role in ovarian follicular gene expression has not been reported. The effects of selenomethionine (SeMet) on gene expression in in vitro ewe follicles and their relationship with immunity and apoptosis were studied. Preovulatory follicles were randomly cultured, and SeMet was added to the culture, followed by incubation for 24 h. Total RNA was extracted from follicles and placed on a microarray chip. Gene expression was analyzed using GenArise and classified using the DAVID v6.8 bioinformatics program based on the Gene Ontology and Kyoto Encyclopedia for Genes and Genomes (KEGG). Gene pathways were designed using Cytoscape v3.7.2. There were 2,538 differentially expressed genes (DEGs): 1,228 upregulated and 1,310 downregulated. The upregulated genes were classified into 32, 18, and 12 nodes related to biological processes, cellular components, and molecular functions, respectively. KEGG assigned these genes to 41 metabolic and signaling pathways. 94 genes were involved in eight pathways associated with immune processes. The expression levels of CD8, NFAT2, and CD48 were quantified using RT-qPCR. Selenium activated gene expression in the in vitro preovulatory follicles of ewes, some of which were related to the immune system. The relationship among CD8, NFAT2, and CD48 genes suggests a possible immune pathway related to follicular apoptosis regulation

Inducción eficiente de brotes adventicios en cotiledones de Pinus maximartinezii Rzedowski

Pinus maximartinezii Rzedowski is a nut pine native to Mexico that currently is considered as an endangered species because of disturbance of populations and natural habitat, as well as its limited geographic distribution. Even though such technologies as tissue culture could represent an alternative for its conservation and propagation, the existing literature for this pine is scarce. In this paper a protocol that allows an efficient differentiation of adventitious shoots for this species is presented. Different types of explants (embryos and cotyledons) were evaluated regarding their capacity to differentiate adventitious shoots. Explants from cotyledons showed the best response, so they were cultivated in a modified Schenk and Hildebrandt (SH) medium supplemented with four different concentrations (2.2-16.8 mg L-1) of N6-benzyladenine (BA). Percentages of explants forming shoots and number of shoots developed per explant were statistically different among the tested concentrations. The 16.8 mg L-1 of BA concentration induced the largest percentage of explants forming shoots (53.5) and the highest number of shoots developed per explant (29.1) after 14 weeks of culture. Three percent of the individual shoots produced roots. The developed methodology allows differentiation of adventitious shoots of Pinus maximartinezii from cotyledon explants, with a multiplication rate significantly higher than the one obtained by other authors.Pinus maximartinezii Rzedowski es una especie de piñonero originaria de México, considerada en peligro de extinción debido a la alteración de sus poblaciones y de su hábitat, así como a su distribución geográfica restringida. A pesar de que tecnologías como el cultivo de tejidos podrían ser una alternativa para su conservación y propagación, la literatura existente al respecto es escasa. En este trabajo se presenta un protocolo que permite la diferenciación eficiente de brotes adventicios de este taxon. Se probaron embriones y cotiledones en cuanto a su capacidad para formar yemas adventicias. Los segundos mostraron la mejor respuesta y fueron entonces cultivados en el medio de Schenk y Hildebrandt (SH) modificado, suplementado con cuatro concentraciones (2.2 a 16.8 mg L-1) deN6-benciladenina (BA). El porcentaje de explantes que produjeron brotes y el número de brotes formados en éstos fue estadísticamente diferente entre los niveles de BA probados; con 16.8 mg L-1 se indujo el mayor porcentaje de órganos que formaron brotes (53.5) y el número más alto de brotes generados por explante (29.1) a las 14 semanas de cultivo; de los vástagos individualizados, 3% formó raíces. La metodología desarrollada permite la diferenciación de yemas adventicias de P. maximartinezii a partir del cultivo de cotiledones, con una tasa de multiplicación significativamente superior a la obtenida por otros autores

Inducción eficiente de brotes adventicios en cotiledones de Pinus maximartinezii Rzedowski

Pinus maximartinezii Rzedowski is a nut pine native to Mexico that currently is considered as an endangered species because of disturbance of populations and natural habitat, as well as its limited geographic distribution. Even though such technologies as tissue culture could represent an alternative for its conservation and propagation, the existing literature for this pine is scarce. In this paper a protocol that allows an efficient differentiation of adventitious shoots for this species is presented. Different types of explants (embryos and cotyledons) were evaluated regarding their capacity to differentiate adventitious shoots. Explants from cotyledons showed the best response, so they were cultivated in a modified Schenk and Hildebrandt (SH) medium supplemented with four different concentrations (2.2-16.8 mg L-1) of N6-benzyladenine (BA). Percentages of explants forming shoots and number of shoots developed per explant were statistically different among the tested concentrations. The 16.8 mg L-1 of BA concentration induced the largest percentage of explants forming shoots (53.5) and the highest number of shoots developed per explant (29.1) after 14 weeks of culture. Three percent of the individual shoots produced roots. The developed methodology allows differentiation of adventitious shoots of Pinus maximartinezii from cotyledon explants, with a multiplication rate significantly higher than the one obtained by other authors.Pinus maximartinezii Rzedowski es una especie de piñonero originaria de México, considerada en peligro de extinción debido a la alteración de sus poblaciones y de su hábitat, así como a su distribución geográfica restringida. A pesar de que tecnologías como el cultivo de tejidos podrían ser una alternativa para su conservación y propagación, la literatura existente al respecto es escasa. En este trabajo se presenta un protocolo que permite la diferenciación eficiente de brotes adventicios de este taxon. Se probaron embriones y cotiledones en cuanto a su capacidad para formar yemas adventicias. Los segundos mostraron la mejor respuesta y fueron entonces cultivados en el medio de Schenk y Hildebrandt (SH) modificado, suplementado con cuatro concentraciones (2.2 a 16.8 mg L-1) deN6-benciladenina (BA). El porcentaje de explantes que produjeron brotes y el número de brotes formados en éstos fue estadísticamente diferente entre los niveles de BA probados; con 16.8 mg L-1 se indujo el mayor porcentaje de órganos que formaron brotes (53.5) y el número más alto de brotes generados por explante (29.1) a las 14 semanas de cultivo; de los vástagos individualizados, 3% formó raíces. La metodología desarrollada permite la diferenciación de yemas adventicias de P. maximartinezii a partir del cultivo de cotiledones, con una tasa de multiplicación significativamente superior a la obtenida por otros autores

Genetic transformation of garlic (Allium sativum L.) with tobacco chitinase and glucanase genes for tolerance to the fungus Sclerotium cepivorum

Garlic yield and quality have decreased due to white rot disease caused by Sclerotium cepivorum Berk. A transformation protocol to introduce tobacco chitinase and glucanase genes into garlic embryogenic calli using Agrobacterium tumefaciens has been established. LBA4404 strain having pC2301CHGLU plasmid with TaCh, glu, gus and nptII genes (coding for chitinase, glucanase, β-glucuronidase and neomycin phosphotransferase, respectively) was used. 30 putative transgenic clones were obtained from inoculated calli after six months. Histochemical assay revealed high gus activity in 43% of the clones. Molecular analysis of transgenic plants showed 92% of the clones carried TaCh gene. Eight culture media for plant regeneration from transgenic calli were evaluated; MTDZ-1 (thidiazuron 1 mg/l) medium induced the highest number of plants (38.4 plants). Transgenic plants were grown in the greenhouse and they developed normally. S. cepivorum in vitro bioassays showed 41 to 60% of mycelial invasion in the transgenic plants, and 80% in non-transgenic plants (control). Transformed plants were not completely resistant, but they showed a delay in fungal infection. This is the first report on the introduction of fungal resistance genes in garlic.Keywords: Allium sativum, Agrobacterium tumefaciens, Sclerotium cepivorum, glucanase, chitinaseAfrican Journal of Biotechnology Vol. 12(22), pp. 3482-349

Inducción eficiente de brotes adventicios en cotiledones de Pinus maximartinezii Rzedowski

Pinus maximartinezii Rzedowski is a nut pine native to Mexico that currently is considered as an endangered species because of disturbance of populations and natural habitat, as well as its limited geographic distribution. Even though such technologies as tissue culture could represent an alternative for its conservation and propagation, the existing literature for this pine is scarce. In this species is presented. Different types of explants (embryos and cotyledons) were evaluated regarding their capacity to differentiate adventitious schoots. Explants from cotyledons showed the best response, so they were cultivated in a modified Shenk and Hildebrandt (SH) medium supplemented with four different concentratios (2.2 a 16.8 mg L-1) of N6-benzyladenine (BA). Percentages of explants forming shoots and number of shoots developed per explant were statistically different a mong the tested concentrations. The 16.8 mg L-1 of BA concentration induced the largest percentage of explants forming shoots and number of shoots (53.5) and the highest number of shoots developed per explant (29.1) after 14 weeks of culture. Three percent of the individual shoots produced roots. The developed methodology allows differentiation of adventitious shoots of Pinus maximartinezii from cotyledon explants, with a multiplication rate significantly higher than the one obtained by other authors.Pinus maximartinezii Rzedowski es una especie de piñonero originaria de México, considerada en peligro de extinción debido a la alteración de sus poblaciones y de su hábitat, así como a su distribución geográfica retringida. A pesar de que tecnologías como el cultivo de tejidos podrían ser una alternativa para su conservación y propagación, la literatura existente al respecto es escasa. En este trabajo se presenta un protocolo que permite la diferenciación eficiente de brotes adventicios de este taxon. Se probaron embriones y cotiledones en cuanto a su capacidad para formar yemas adventicias. Los segundos mostraron la mejor respuesta y fueron entonces cultivados en el medio de Shenk y Hildebrandt (SH) modificado, suplementado con cuatro concentaciones (2.2 a 16.8 mg L-1) de deN6 -benciladenina (BA). El porcentaje de explantes que produjeron brotes y el número de brotes formados en éstos fue estadísticamente diferente entre los niveles de BA probados; con 16.8 mg L-1 se indujo el mayor porcentaje de órganos que formaron brotes (53.5) y el número más alto de brotes generados por explante (29.1) a las 14 semanas de cultivo de cotiledones, con una tasa de multiplicación siginificativamente superior a la obtenida por otros autores

Regeneración in vitro de plantas de cebolla (Allium Cepa l.)

La cebolla (Allium cepa L.) es una de las principales hortalizas cultivadas en México; sin embargo, no hay estudios relacionados con la regeneración in vitro de variedades comerciales sembradas en nuestro país. En este trabajo se presenta una metodología que permite la regeneración de plantas de las variedades Cristal y El Toro. Explantes de ápices de raíces de plántulas de 2 d de edad se cultivaron en el medio de Chu et al. (N6) más dos concentraciones de ácido 2, 4-diclorofenoxiacético (2, 4-D) (0.5 ó 1.0 mg L-----1) y con o sin 6-furfurilaminopurina (cinetina) (0.5 ó 1.0 mg L-----1). El porcentaje de explantes que formaron plantas y el número de plantas formadas por explante no fue estadísticamente diferente (p>0.05) entre los cuatro medios evaluados. La variedad Cristal mostró mayor porcentaje de explantes con plantas y mayor número de plantas por explante. Se obtuvieron plantas después de 16 semanas de haber iniciado el cultivo y éstas formaron microbulbos3, los cuales alcanzaron hasta 3 cm de diámetro (bulbos)4 cuando se transplantaron en invernadero. El protocolo desarrollado permite la propagación de variedades de importancia económica para nuestro país. La respuesta in vitro obtenida superó a la reportada por otros autores. Los callos embriogénicos obtenidos pueden emplearse para incorporar transgenes a la planta de cebolla

Diversidad genética en accesiones de 10 razas mexicanas de maíz de altitudes intermedias

La diversidad del maíz (Zea mays L.) en México es amplia y aún existe la necesidad de llevar a cabo trabajos que permitan discernir la variación dentro y entre grupos raciales y establecer colecciones de referencia racial para su entendimiento. Se valoró la diversidad morfológica de poblaciones representativas de 10 razas de maíz de México. En el ciclo primavera-verano de 2010 se establecieron experimentos con 88 accesiones representativas de las razas Bofo, Celaya, Coscomatepec, Dulce de Jalisco, Elotes Occidentales, Mushito, Palomero de Jalisco, Serrano de Jalisco, Tablilla de Ocho, y Zamorano Amarillo, en las localidades de Roque, Guanajuato y Ciudad Guzmán, Jalisco, bajo un diseño experimental de bloques incompletos, se midieron 30 caracteres morfológicos. El análisis de varianza indicó diferencias significativas entre las accesiones para todos los caracteres (variables). El análisis de repetibilidad reflejó que 16 caracteres presentaron un coeficiente ≥3, éstos fueron los menos afectados por el ambiente. En el análisis de componentes principales y conglomerados hubo variación dentro y entre razas, con una dispersión continua, que permitió identificar cuatro complejos raciales. El grupo I lo integraron accesiones de Bofo, el II de Celaya, el III de Dulce de Jalisco y el IV de Elotes Occidentales, las razas restantes se agregan en su mayoría en el grupo II como subgrupos. Este estudio confirmó agrupamientos de accesiones en razas bien definidas y representadas en los bancos de germoplasma. Es necesario realizar estudios más profundos en razas con pocas accesiones para lograr una mejor definición racial. Palabras clave: análisis multivariado, caracteres morfológico, grupos racialesThe diversity of maize (Zea mays L.) in Mexico is wide and there is still a need to carry out works that allow to discern the variation within and between racial groups and establish collections of racial reference for their understanding. The morphological diversity of representative populations of 10 mexican maize races was assessed. In the spring-summer cycle of 2010, experiments were established with 88 representative accessions of Bofo, Celaya, Coscomatepec, Dulce de Jalisco, Elotes Occidentales, Mushito, Palomero de Jalisco, Serrano de Jalisco, Tablilla de Ocho, and Zamorano Amarillo races, in the localities of Roque, Guanajuato and Ciudad Guzmán, Jalisco, under an experimental design of incomplete blocks, 30 morphological characters were measured. The analysis of variance indicated significant differences among the accessions for all the characters (variables). The repeatability analysis showed that 16 characters had a coefficient ≥ 3.0, these were the least affected by the environment. In the analysis of main components and conglomerates, variation within and between races was observed, with a continuous dispersion, but which allowed the identification of four racial complexes. Group I was made up of accessions mainly from Bofo, Celaya II, Dulce de Jalisco III and Elotes Occidentales IV, the remaining races are mostly added in group II as subgroups. This study confirmed clustering of accessions in well-defined races and represented in germplasm banks. It is necessary to conduct deeper studies in races with few accessions to achieve a better racial definition. Keywords: morphological characters, multivariate analysi, racial group

Distribution, phylogeny, and pathogenicity of Xanthomonas albilineans causing sugarcane leaf scald in Mexico

International audienceDisease outbreaks attributed to leaf scald of sugarcane caused by Xanthomonas albilineans were recently reported in southern Mexico. In this study, the distribution of leaf scald was investigated in the main sugarcane producing-states in Mexico. The disease was found in eight of 14 sugarcane-growing states and in 12 of 31 fields. In contaminated fields, incidence of leaf scald based on symptomatic plants ranged from 3 to 15%. The causal agent was identified by phylogenetic reconstruction using a single concatenated sequence of four genes (16S rRNA, fusA, leuS, and rpiA). Twelve X. albilineans isolates from different locations in Mexico produced disease symptoms after inoculation into stalks of susceptible variety Mex 69–290. Microscopic examination of infected stalks revealed structural changes within vascular and non-vascular tissues. These alterations reflected acute disease development and highlighted the importance of selecting varieties resistant to X. albilineans in breeding programs in Mexico