Reading Between the Lines of Teaching and Learning

Some students lack reading skills due to biological or environmental factors. Accordingly, in my role as an educator, I would like to know if Dialogic Reading Strategies can help Spanish speaking caregivers to facilitate an interactive reading routine at home with their child

Expansive evolution of the TREHALOSE-6-PHOSPHATE PHOSPHATASE gene family in Arabidopsis

Trehalose is a nonreducing sugar used as a reserve carbohydrate and stress protectant in a variety of organisms. While higher plants typically do not accumulate high levels of trehalose, they encode large families of putative trehalose biosynthesis genes. Trehalose biosynthesis in plants involves a two-step reaction in which trehalose-6-phosphate (T6P) is synthesized from UDPglucose and glucose-6-phosphate (catalyzed by T6P synthase [TPS]), and subsequently dephosphorylated to produce the disaccharide trehalose (catalyzed by T6P phosphatase [TPP]). In Arabidopsis (Arabidopsis thaliana), 11 genes encode proteins with both TPS- and TPP-like domains but only one of these (AtTPS1) appears to be an active (TPS) enzyme. In addition, plants contain a large family of smaller proteins with a conserved TPP domain. Here, we present an in-depth analysis of the 10 TPP genes and gene products in Arabidopsis (TPPA-TPPJ). Collinearity analysis revealed that all of these genes originate from whole-genome duplication events. Heterologous expression in yeast (Saccharomyces cerevisiae) showed that all encode active TPP enzymes with an essential role for some conserved residues in the catalytic domain. These results suggest that the TPP genes function in the regulation of T6P levels, with T6P emerging as a novel key regulator of growth and development in higher plants. Extensive gene expression analyses using a complete set of promoter-beta-glucuronidase/green fluorescent protein reporter lines further uncovered cell- and tissue-specific expression patterns, conferring spatiotemporal control of trehalose metabolism. Consistently, phenotypic characterization of knockdown and overexpression lines of a single TPP, AtTPPG, points to unique properties of individual TPPs in Arabidopsis, and underlines the intimate connection between trehalose metabolism and abscisic acid signaling

Musgos cultivados, indicadores ambientales de contaminación atmosférica

La contaminación atmosférica se ha asociado a diversas enfermedades respiratorias y cardiovasculares (Pan et al., 2015; Yang et al., 2015; Zhang et al., 2015). Es por ello que hoy en día la calidad del aire es un tema de gran interés, tanto en el aspecto ambiental como de salud (Zarazúa et al., 2013). Sin embargo, el monitoreo convencional de los contaminantes atmosféricos no siempre es posible debido a los costos generados por la adquisición y mantenimiento de los equipos tecnológicos necesarios (Ares et al., 2012; Barandovski et al.,2015). Para contrarrestar esta situación, se tiene como alternativa el uso de organismo biológicos como biomonitores de los contaminantes (Malizia et al., 2012; Salo, 2014;Stankovic et al., 2014).Los musgos han demostrado ser muy útiles como bioindicadores de la contaminación del aire. El presente trabajo representa una alternativa a los tipos de monitoreo tradicionales (pasivo y activo), ya que propone evitar la extracción del musgo nativo de los sitios de monitoreo; en su lugar plantea el cultivo in vitro del musgo y su posterior exposición en los sitios de monitoreo. El protocolo incluye la identificación de la especie, obtención del esporofito con la cápsula cerrada, la esterilización de la cápsula de esporas con una solución de NaClO. Posteriormente la cápsula se rompe y se liberan las esporas en agua estéril, para ser dispersadas en medio BCD para su cultivo. La incubación de las esporas ocurre a temperatura e intensidad de luz controlada, condiciones que se mantienen constantes hasta que la planta produce gametofitos. Por este método se asegura la obtención de musgo no contaminado para su posterior exposición a la contaminación atmosférica. El biomonitoreo resulta ser un método relativamente económico y fácil de implementar, por lo que es una alternativa viable para ser desarrollada en lugares en donde no se cuente con la infraestructura para monitorear la calidad del aire.Universidad Autónoma del Estado de México - CONACY

Trehalose Metabolism: From Osmoprotection to Signaling

Trehalose is a non-reducing disaccharide formed by two glucose molecules. It is widely distributed in Nature and has been isolated from certain species of bacteria, fungi, invertebrates and plants, which are capable of surviving in a dehydrated state for months or years and subsequently being revived after a few hours of being in contact with water. This disaccharide has many biotechnological applications, as its physicochemical properties allow it to be used to preserve foods, enzymes, vaccines, cells etc., in a dehydrated state at room temperature. One of the most striking findings a decade ago was the discovery of the genes involved in trehalose biosynthesis, present in a great number of organisms that do not accumulate trehalose to significant levels. In plants, this disaccharide has diverse functions and plays an essential role in various stages of development, for example in the formation of the embryo and in flowering. Trehalose also appears to be involved in the regulation of carbon metabolism and photosynthesis. Recently it has been discovered that this sugar plays an important role in plant-microorganism interactions

A pivotal role for starch in the reconfiguration of 14C-partitioning and allocation in Arabidopsis thaliana under short-term abiotic stress.

Plant carbon status is optimized for normal growth but is affected by abiotic stress. Here, we used 14C-labeling to provide the first holistic picture of carbon use changes during short-term osmotic, salinity, and cold stress in Arabidopsis thaliana. This could inform on the early mechanisms plants use to survive adverse environment, which is important for efficient agricultural production. We found that carbon allocation from source to sinks, and partitioning into major metabolite pools in the source leaf, sink leaves and roots showed both conserved and divergent responses to the stresses examined. Carbohydrates changed under all abiotic stresses applied; plants re-partitioned 14C to maintain sugar levels under stress, primarily by reducing 14C into the storage compounds in the source leaf, and decreasing 14C into the pools used for growth processes in the roots. Salinity and cold increased 14C-flux into protein, but as the stress progressed, protein degradation increased to produce amino acids, presumably for osmoprotection. Our work also emphasized that stress regulated the carbon channeled into starch, and its metabolic turnover. These stress-induced changes in starch metabolism and sugar export in the source were partly accompanied by transcriptional alteration in the T6P/SnRK1 regulatory pathway that are normally activated by carbon starvation

Presence of flower thrips Frankliniella schultzei in ornamental plants

Objective: to report the presence of Frankliniella schultzei in geranium (Pelargonium hortorum) and vinca (Catharanthus roseus) plants, in greenhouses in the State of Morelos, Mexico. Design/methodology/approach: geranium and vinca plants were sampled in greenhouses located in the Municipality of Jojutla, Morelos, Mexico. The collected specimens were brown to dark brown color, were processed and mounted on glass slides and identified by means of taxonomic keys and the use of a conventional microscope. Results: the specimens collected in geranium and vinca presented morphological characteristics corresponding to the species Frankliniella schultei. Limitations on study/implications: monitoring of the species is necessary now that its presence is known in at least two areas of Mexico: the west and center of the country. Findings/conclusions: in Mexico, Frankliniella schultzei had only been reported in the west, with this report it is now known that it is also located in the central part of the country.Objective: To report on the presence of Frankliniella schultzei in geranium (Pelargonium hortorum) and periwinkle (Catharanthus roseus) plants in greenhouses in the State of Morelos, Mexico. Design/Methodology/Approach: We sampled geranium and periwinkle plants in greenhouses in the municipality of Jojutla, Morelos, Mexico. The collected specimens—of light to dark brown color—were processed, mounted on glass slides to be observed through a conventional light microscope, and identified with taxonomic keys. Results: The specimens collected in the geranium and periwinkle plants presented morphological traits that conform to the species Frankliniella schultzei. Study limitations/Implications: Monitoring the species is necessary because its presence has been identified in at least two regions of Mexico: West and Center. Findings/Conclusions: Frankliniella schultzei had only been located in western Mexico. This report shows that the species is also found in the central region of the country

Molecular processes underlying the floral transition in the soybean shoot apical meristem

The transition to flowering is characterized by a shift of the shoot apical meristem (SAM) from leaf production to the initiation of a floral meristem. The flowering process is of vital importance for agriculture, but the associated events or regulatory pathways in the SAM are not well understood, especially at a system level. To address this issue, we have used a GeneChip® containing 37 744 probe sets to generate a temporal profile of gene expression during the floral initiation process in the SAM of the crop legume, soybean (Glycine max). A total of 331 transcripts displayed significant changes in their expression profiles. The in silico and RT-PCR analysis on differentially regulated transcripts implies the intriguing involvement of sugar, auxin or abscisic acid (ABA) in events prior to the induction of floral homeotic transcripts. The novel involvement of ABA in the floral transition is further implicated by immunoassay, suggesting an increase in ABA levels in the SAM during this developmental transition. Furthermore, in situ localization, together with in silico data demonstrating a marked enhancement of abiotic stress-related transcripts, such as trehalose metabolism genes in SAMs, points to an overlap of abiotic stress and floral signalling pathways