Chloroplast Vesiculation and Induced and Expression During Tomato Flower Pedicel Abscission.

Abscission is a tightly regulated process in which plants shed unnecessary, infected, damaged, or aging organs, as well as ripe fruits, through predetermined abscission zones in response to developmental, hormonal, and environmental signals. Despite its importance, the underlying mechanisms remain incompletely understood. This study highlights the deleterious effects of abscission on chloroplast ultrastructure in the cells of the tomato flower pedicel abscission zone, revealing spatiotemporal differential gene expression and key transcriptional networks involved in chloroplast vesiculation during abscission.

Candidate pathogenicity factor/effector proteins of ' Phytoplasma solani' modulate plant carbohydrate metabolism, accelerate the ascorbate-glutathione cycle, and induce autophagosomes.

The pathogenicity of intracellular plant pathogenic bacteria is associated with the action of pathogenicity factors/effectors, but their physiological roles for most phytoplasma species, including ' Phytoplasma solani' are unknown. Six putative pathogenicity factors/effectors from six different strains of '. P.

Seed Germination of Invasive and Potentially Invasive .

and are alien plant species in Europe. The former is considered invasive and more widespread. In order to develop effective and safe eradication and plant disposal methods, the present research focused on the seed germination of the two species.

Geographical and Temporal Diversity of ' Phytoplasma solani' in Wine-Growing Regions in Slovenia and Austria.

As the causal agent of the grapevine yellows disease Bois noir, ' Phytoplasma solani' has a major economic impact on grapevines. To improve the control of Bois noir, it is critical to understand the very complex epidemiological cycles that involve the multiple ". P.

Differential Response of Grapevine to Infection with ' Phytoplasma solani' in Early and Late Growing Season through Complex Regulation of mRNA and Small RNA Transcriptomes.

Bois noir is the most widespread phytoplasma grapevine disease in Europe. It is associated with ' Phytoplasma solani', but molecular interactions between the causal pathogen and its host plant are not well understood. In this work, we combined the analysis of high-throughput RNA-Seq and sRNA-Seq data with interaction network analysis for finding new cross-talks among pathways involved in infection of grapevine cv.

New Cross-Talks between Pathways Involved in Grapevine Infection with ' Phytoplasma solani' Revealed by Temporal Network Modelling.

Understanding temporal biological phenomena is a challenging task that can be approached using network analysis. Here, we explored whether network reconstruction can be used to better understand the temporal dynamics of bois noir, which is associated with ' Phytoplasma solani', and is one of the most widespread phytoplasma diseases of grapevine in Europe. We proposed a methodology that explores the temporal network dynamics at the community level, i.

Miniaturization, Genome Size, and Biological Size in a Diverse Clade of Salamanders.

AbstractGenome size (C-value) can affect organismal traits across levels of biological organization from tissue complexity to metabolism. Neotropical salamanders show wide variation in genome and body sizes, including several clades with miniature species. Because miniaturization imposes strong constraints on morphology and development and because genome size is strongly correlated with cell size, we hypothesize that body size has played an important role in the evolution of genome size in bolitoglossine salamanders.

Precision transcriptomics of viral foci reveals the spatial regulation of immune-signaling genes and identifies RBOHD as an important player in the incompatible interaction between potato virus Y and potato.

Whereas the activation of resistance (R) proteins has been intensively studied, the downstream signaling mechanisms leading to the restriction of the pathogen remain mostly unknown. We studied the immunity network response conditioned by the potato Ny-1 gene against potato virus Y. We analyzed the processes in the cell death zone and surrounding tissue on the biochemical and gene expression levels in order to reveal the spatiotemporal regulation of the immune response.

The pattern of 1-aminocyclopropane-1-carboxylate oxidase induction in the tomato leaf petiole abscission zone is independent of expression of the ribonuclease-LX-encoding LeLX gene.

The abscission of tomato leaves occurs in the petiole abscission zone, and its late stage includes two spatially divided processes: cell separation and programmed cell death (PCD). Both of these processes are regulated by ethylene. The last step in ethylene biosynthesis is conversion of 1-aminocyclopropane-1-carboxylic acid to ethylene, which is catalysed by the enzyme 1-aminocyclopropane-1-carboxylate oxidase (ACO); however, the location of ACO in the leaf petiole abscission zone is not known.

Impact of polyethylene microbeads on the floating freshwater plant duckweed Lemna minor.

Microplastics (MP), small plastic particles below 5 mm, have become one of the central concerns of environmental risk assessment. Microplastics are continuously being released into the aquatic environment either directly through consumer products or indirectly through fragmentation of larger plastic materials. The aim of our study was to investigate the effect of polyethylene microbeads from cosmetic products on duckweed (Lemna minor), a freshwater floating plant.

1-Aminocyclopropane-1-Carboxylate Oxidase Induction in Tomato Flower Pedicel Phloem and Abscission Related Processes Are Differentially Sensitive to Ethylene.

Ethylene has impact on several physiological plant processes, including abscission, during which plants shed both their vegetative and reproductive organs. Cell separation and programmed cell death are involved in abscission, and these have also been correlated with ethylene action. However, the detailed spatiotemporal pattern of the molecular events during abscission remains unknown.

The Pseudomonas aeruginosa RhlR-controlled aegerolysin RahU is a low-affinity rhamnolipid-binding protein.

The opportunistic pathogen Pseudomonas aeruginosa uses quorum-sensing systems to regulate collective behaviour in response to the environment, by linking the expression of particular genes to population density. The quorum-sensing transcription factors LasR and RhlR and their cognate N-acyl-homoserine lactone (HSL) signals N-3-oxo-dodecanoyl-L-HSL (3OC12-HSL) and N-butanoyl-L-HSL (C4-HSL) control the expression of several hundred genes, which include those involved in virulence and biofilm formation. Here, we have focused on regulation of the expression of the putative virulence factor gene, rahU.

Vegetable cells in urinary samples of patients with bricker ileal conduit.

During routine cytopathological evaluation of urines for malignant cells we have occasionally noticed vegetable cells that were only present in patients with Bricker ileal conduit. We wanted to identify the means and sources of contamination of urinary samples from these patients. During the period between May and November 2010, 637 urinary samples were routinely evaluated for malignant cells.

Impaired auxin biosynthesis in the defective endosperm18 mutant is due to mutational loss of expression in the ZmYuc1 gene encoding endosperm-specific YUCCA1 protein in maize.

The phytohormone auxin (indole-3-acetic acid [IAA]) plays a fundamental role in vegetative and reproductive plant development. Here, we characterized a seed-specific viable maize (Zea mays) mutant, defective endosperm18 (de18) that is impaired in IAA biosynthesis. de18 endosperm showed large reductions of free IAA levels and is known to have approximately 40% less dry mass, compared with De18.

Endoreduplication preferentially occurs at the proximal side of the abscission zone during abscission of tomato leaf.

Endoreduplication is a cell cycle variant in which multiple rounds of DNA replication occur without subsequent mitosis, resulting in polyploid cells. Although cells with endoreduplicated nuclei were ubiquitously distributed throughout the abscission zone (AZ) of tomato leaf before abscission induction by ethylene, endoreduplication was detected mostly on the proximal side of the AZ after induction. The possible association between endoreduplication and intensive membrane trafficking in cells at the proximal side of the AZ is discussed.

Perforin activity at membranes leads to invaginations and vesicle formation.

The cytotoxic cell granule secretory pathway is essential for immune defence. How the pore-forming protein perforin (PFN) facilitates the cytosolic delivery of granule-associated proteases (granzymes) remains enigmatic. Here we show that PFN is able to induce invaginations and formation of complete internal vesicles in giant unilamellar vesicles.

Programmed cell death occurs asymmetrically during abscission in tomato.

Abscission occurs specifically in the abscission zone (AZ) tissue as a natural stage of plant development. Previously, we observed delay of tomato (Solanum lycopersicum) leaf abscission when the LX ribonuclease (LX) was inhibited. The known association between LX expression and programmed cell death (PCD) suggested involvement of PCD in abscission.

Distribution of Potato virus Y in potato plant organs, tissues, and cells.

The distribution of Potato virus Y (PVY) in the systemically infected potato (Solanum tuberosum) plants of the highly susceptible cultivar Igor was investigated. Virus presence and accumulation was analyzed in different plant organs and tissues using real-time polymerase chain reaction and transmission electron microscopy (TEM) negative staining methods. To get a complete insight into the location of viral RNA within the tissue, in situ hybridization was developed and optimized for the detection of PVY RNA at the cellular level.

Human perforin employs different avenues to damage membranes.

Perforin (PFN) is a pore-forming protein produced by cytotoxic lymphocytes that aids in the clearance of tumor or virus-infected cells by a mechanism that involves the formation of transmembrane pores. The properties of PFN pores and the mechanism of their assembly remain unclear. Here, we studied pore characteristics by functional and structural methods to show that perforin forms pores more heterogeneous than anticipated.

A toxin-based probe reveals cytoplasmic exposure of Golgi sphingomyelin.

Although sphingomyelin is an important cellular lipid, its subcellular distribution is not precisely known. Here we use a sea anemone cytolysin, equinatoxin II (EqtII), which specifically binds sphingomyelin, as a new marker to detect cellular sphingomyelin. A purified fusion protein composed of EqtII and green fluorescent protein (EqtII-GFP) binds to the SM rich apical membrane of Madin-Darby canine kidney (MDCK) II cells when added exogenously, but not to the SM-free basolateral membrane.

A cellular study of teosinte Zea mays subsp. parviglumis (Poaceae) caryopsis development showing several processes conserved in maize.

The evolutionary history of maize (Zea mays subsp. mays) is of general interest because of its economic and scientific importance. Here we show that many cellular traits described previously in developing caryopses of maize are also seen in its wild progenitor teosinte (Zea mays subsp.

A comparative study on the role of cytokinins in caryopsis development in the maize miniature1 seed mutant and its wild type.

We report here on a comparative developmental profile of plant hormone cytokinins in relation to cell size, cell number and endoreduplication in developing maize caryopsis of a cell wall invertase-deficient miniature1 (mn1) seed mutant and its wild type, Mn1, genotype. Both genotypes showed extremely high levels of total cytokinins during the very early stages of development, followed by a marked and genotype specific reduction. While the decrease of cytokinins in Mn1 was associated with their deactivation by 9-glucosylation, the absolute and the relative part of active cytokinin forms was higher in the mutant.

Epithelial thickness and lipid droplets in the hepatopancreas of Porcellio scaber (Crustacea: Isopoda) in different physiological conditions.

We investigated the morphometric characteristics of the hepatopancreatic epithelium in the terrestrial isopod Porcellio scaber during acclimatization to laboratory conditions, during the daily cycle, the molt cycle, and fasting. The hepatopancreatic epithelium was analyzed using computer-assisted microscopy of serial sections of the hepatopancreatic tubes. In addition, the abundance, the distribution, and the size of lipid droplets in the hepatopancreatic epithelium were recorded.

Kinetics of cholesterol extraction from lipid membranes by methyl-beta-cyclodextrin--a surface plasmon resonance approach.

The kinetics of cholesterol extraction from cellular membranes is complex and not yet completely understood. In this paper we have developed an experimental approach to directly monitor the extraction of cholesterol from lipid membranes by using surface plasmon resonance and model lipid systems. Methyl-beta-cyclodextrin was used to selectively remove cholesterol from large unilamellar vesicles of various compositions.

Properties of nonfused liposomes immobilized on an L1 Biacore chip and their permeabilization by a eukaryotic pore-forming toxin.

The L1 chip is used intensively for protein-membrane interaction studies in Biacore surface plasmon resonance systems. The exact form of captured lipid membranes on the chip is, however, not precisely known. Evidence exists that the vesicles both remain intact after the binding to the chip and fuse to form a large single-bilayer membrane.