Proteomic and metabolomic integration reveals the effects of pre-flowering cytokinin applications on central carbon metabolism in table grape berries.

Consumers around the world prefer high quality table grapes. To achieve higher quality traits at ripening, grapevine producers apply different plant growth regulators. The synthetic cytokinin forchlorfenuron N-(2-chloro-4-pyridinyl)-N'-phenylurea (CPPU) is widely used, its effect on grape quality is poorly understood. We hypothesized that the use of CPPU in pre-flowering can lead to changes in the metabolism that affects grape quality at harvest. Therefore, we investigated the role of CPPU applications on the quality of grapes by integrating proteomics and metabolomics. CPPU-treated grapevines showed a significant increase in berry size and firmness. Proteomic analyses indicated that CPPU-treated berries accumulated enzymes associated with carbohydrate metabolism, glycolysis, and tricarboxylic acid (TCA) cycle at harvest. Metabolomic analyses showed shifts in the abundance of compounds associated with carbohydrate metabolism and TCA cycle in CPPU-treated grapes. These findings suggest that CPPU applications modulate central carbon metabolism, improving grape berry quality.

Metabolomic and biochemical analysis of mesocarp tissues from table grape berries with contrasting firmness reveals cell wall modifications associated to harvest and cold storage.

Tissue texture influences the grape berry consumers acceptance. We studied the biological differences between the inner and outer mesocarp tissues in hard and soft berries of table grapes cv NN107. Texture analysis revealed lower levels of firmness in the inner mesocarp as compared with the outer tissue. HPAEC-PAD analysis showed an increased abundance of cell wall monosaccharides in the inner mesocarp of harder berries at harvest. Immunohistochemical analysis displayed differences in homogalacturonan methylesterification and cell wall calcium between soft and hard berries. This last finding correlated with a differential abundance of calcium measured in the alcohol-insoluble residues (AIR) of the inner tissue of the hard berries. Analysis of abundance of polar metabolites suggested changes in cell wall carbon supply precursors, providing new clues in the identification of the biochemical factors that define the texture of the mesocarp of grape berries.

Pre-Anthesis Cytokinin Applications Increase Table Grape Berry Firmness by Modulating Cell Wall Polysaccharides.

The use of plant growth regulators (PGRs) is widespread in commercial table grape vineyards. The synthetic cytokinin CPPU is a PGR that is extensively used to obtain higher quality grapes. However, the effect of CPPU on berry firmness is not clear. The current study investigated the effects of pre-anthesis applications (BBCH15 and BBCH55 stages) of CPPU on 'Thompson Seedless' berry firmness at harvest through a combination of cytological, morphological, and biochemical analyses. Ovaries in CPPU-treated plants presented morphological changes related to cell division and cell wall modification at the anthesis stage (BBCH65). Moreover, immunofluorescence analysis with monoclonal antibodies 2F4 and LM15 against pectin and xyloglucan demonstrated that CPPU treatment resulted in cell wall modifications at anthesis. These early changes have major repercussions regarding the hemicellulose and pectin cell wall composition of mature fruits, and are associated with increased calcium content and a higher berry firmness at harvest.

Cell Wall Calcium and Hemicellulose Have a Role in the Fruit Firmness during Storage of Blueberry (Vaccinium spp.).

The firmness of blueberry is one of its most significant quality attributes. Modifications in the composition of the cell wall have been associated with changes in the fruit firmness. In this work, cell wall components and calcium concentration in two blueberry cultivars with contrasting firmness phenotypes were evaluated at harvest and 30 days cold storage (0 °C). High performance anion-exchange chromatography with pulse amperometric detector (HPAEC-PAD) analysis was performed using the "Emerald" (firmer) and "Jewel" (softer) blueberry cultivars, showing increased glucose in the firmer cultivar after cold storage. Moreover, the LM15 antibody, which recognizes xyloglucan domains, displayed an increased signal in the Emerald cultivar after 30 d cold storage. Additionally, the antibody 2F4, recognizing a homogalacturonan calcium-binding domain, showed a greater signal in the firmer Emerald blueberries, which correlates with a higher calcium concentration in the cell wall. These findings suggest that xyloglucan metabolism and a higher concentration of cell wall calcium influenced the firmness of the blueberry fruit. These results open new perspectives regarding the role of cell wall components as xyloglucans and calcium in blueberry firmness.

Pectin Methylesterases Modulate Plant Homogalacturonan Status in Defenses against the Aphid Myzus persicae.

Because they suck phloem sap and act as vectors for phytopathogenic viruses, aphids pose a threat to crop yields worldwide. Pectic homogalacturonan (HG) has been described as a defensive element for plants during infections with phytopathogens. However, its role during aphid infestation remains unexplored. Using immunofluorescence assays and biochemical approaches, the HG methylesterification status and associated modifying enzymes during the early stage of Arabidopsis (Arabidopsis thaliana) infestation with the green peach aphid (Myzus persicae) were analyzed. Additionally, the influence of pectin methylesterase (PME) activity on aphid settling and feeding behavior was evaluated by free choice assays and the Electrical Penetration Graph technique, respectively. Our results revealed that HG status and HG-modifying enzymes are significantly altered during the early stage of the plant-aphid interaction. Aphid infestation induced a significant increase in total PME activity and methanol emissions, concomitant with a decrease in the degree of HG methylesterification. Conversely, inhibition of PME activity led to a significant decrease in the settling and feeding preference of aphids. Furthermore, we demonstrate that the PME inhibitor AtPMEI13 has a defensive role during aphid infestation, since pmei13 mutants are significantly more susceptible to M. persicae in terms of settling preference, phloem access, and phloem sap drainage.

Facoemulsificación en el síndrome iridocorneal endotelial / Phacoemulsification in the treament of iridocorneal endothelial syndrome

Se presenta el caso de una paciente atendida en el Servicio de Catarata del Centro Oftalmológico Enrique Cabrera de La Habana, con el objetivo de describir el resultado de la cirugía de catarata por facoemulsificación en el síndrome iridocorneal endotelial, por la variante cho choo chop and flip faco. Se muestran las modificaciones biomicroscópicas del segmento anterior, tonometría, densidad celular endotelial y mejor agudeza visual corregida preoperatoria y postoperatoria. Como resultados sobresalientes se señala que biomicroscópicamente hubo mínimas modificaciones en el iris, se logró la normalización de la tensión ocular, se produjo pérdida de menos del 15 por ciento de la densidad celular endotelial y la paciente logró agudeza visual postoperatoria óptima. Se concluye que la cirugía de catarata mediante facoemulsificación resultó una alternativa válida con mejoría visual en un caso con síndrome iridocorneal endotelial, con evolución estable de su enfermedad base

The case of a female patient who was seen at the cataract service of "Enrique Cabrera" ophthalmological center in Havana was presented. The objective was to describe the results of phacoemulsification cataract surgery to treat iridocorneal endothelial syndrome through the cho choo chop and flip phaco variant. The biomicroscopic changes of the anterior segment, the tonometry, the endothelial cell density and the best corrected visual acuity before and after surgery were shown. The main results comprised minimal changes in the iris from the biomicroscopic viewpoint, normalization of ocular tension, loss of less than 15 percent in endothelial cell density and postoperative optimal visual acuity. It was concluded that phacoemulsification cataract surgery proved to be a valid alternative that achieved visual improvement in a case of iridocorneal endothelial syndrome, with stable recovery from the underlying disease

Facoemulsificación en el síndrome iridocorneal endotelial / Phacoemulsification in the treament of iridocorneal endothelial syndrome

Se presenta el caso de una paciente atendida en el Servicio de Catarata del Centro Oftalmológico Enrique Cabrera de La Habana, con el objetivo de describir el resultado de la cirugía de catarata por facoemulsificación en el síndrome iridocorneal endotelial, por la variante cho choo chop and flip faco. Se muestran las modificaciones biomicroscópicas del segmento anterior, tonometría, densidad celular endotelial y mejor agudeza visual corregida preoperatoria y postoperatoria. Como resultados sobresalientes se señala que biomicroscópicamente hubo mínimas modificaciones en el iris, se logró la normalización de la tensión ocular, se produjo pérdida de menos del 15 por ciento de la densidad celular endotelial y la paciente logró agudeza visual postoperatoria óptima. Se concluye que la cirugía de catarata mediante facoemulsificación resultó una alternativa válida con mejoría visual en un caso con síndrome iridocorneal endotelial, con evolución estable de su enfermedad base(AU)

The case of a female patient who was seen at the cataract service of "Enrique Cabrera" ophthalmological center in Havana was presented. The objective was to describe the results of phacoemulsification cataract surgery to treat iridocorneal endothelial syndrome through the cho choo chop and flip phaco variant. The biomicroscopic changes of the anterior segment, the tonometry, the endothelial cell density and the best corrected visual acuity before and after surgery were shown. The main results comprised minimal changes in the iris from the biomicroscopic viewpoint, normalization of ocular tension, loss of less than 15 percent in endothelial cell density and postoperative optimal visual acuity. It was concluded that phacoemulsification cataract surgery proved to be a valid alternative that achieved visual improvement in a case of iridocorneal endothelial syndrome, with stable recovery from the underlying disease(AU)