Engineered Ripening-Specific Accumulation of Polyamines Spermidine and Spermine in Tomato Fruit Upregulates Clustered C/D Box snoRNA Gene Transcripts in Concert with Ribosomal RNA Biogenesis in the Red Ripe Fruit.

Ripening of tomato fruit leads, in general, to a sequential decrease in the endogenous levels of polyamines spermidine (SPD) and spermine (SPM), while the trend for the diamine putrescine (PUT) levels is generally an initial decrease, followed by a substantial increase, and thereafter reaching high levels at the red ripe fruit stage. However, genetic engineering fruit-specific expression of heterologous yeast S-adenosylmethionine (SAM) decarboxylase in tomato has been found to result in a high accumulation of SPD and SPM at the cost of PUT. This system enabled a genetic approach to determine the impact of increased endogenous levels of biogenic amines SPD and SPM in tomato (579HO transgenic line) and on the biogenesis, transcription, processing, and stability of ribosomal RNA (rRNA) genes in tomato fruit as compared with the non-transgenic 556AZ line.

Ethylene and Modulate Expression of Class I Small Heat Shock Protein Genes During Tomato Fruit Ripening.

Heat shock proteins (HSPs) are ubiquitous and highly conserved in nature. Heat stress upregulates their gene expression and now it is known that they are also developmentally regulated. We have studied regulation of small HSP genes during ripening of tomato fruit.

Fruit Architecture in Polyamine-Rich Tomato Germplasm Is Determined via a Medley of Cell Cycle, Cell Expansion, and Fruit Shape Genes.

Shape and size are important features of fruits. Studies using tomatoes expressing under either a constitutive or a fruit-ripening promoter showed obovoid fruit phenotype compared to spherical fruit in controls, suggesting that polyamines (PAs) have a role in fruit shape. The obovoid fruit pericarp exhibited decreased cell layers and pericarp thickness compared to wild-type fruit.

Pathogenesis-Related Protein 1b1 (PR1b1) Is a Major Tomato Fruit Protein Responsive to Chilling Temperature and Upregulated in High Polyamine Transgenic Genotypes.

Plants execute an array of mechanisms in response to stress which include upregulation of defense-related proteins and changes in specific metabolites. Polyamines - putrescine (Put), spermidine (Spd), and spermine (Spm) - are metabolites commonly found associated with abiotic stresses such as chilling stress. We have generated two transgenic tomato lines (556HO and 579HO) that express yeast S-adenosylmethionine decarboxylase and specifically accumulate Spd and Spm in fruits in comparison to fruits from control (556AZ) plants (Mehta et al.

Fruit metabolite networks in engineered and non-engineered tomato genotypes reveal fluidity in a hormone and agroecosystem specific manner.

Introduction: Metabolomics provides a view of endogenous metabolic patterns not only during plant growth, development and senescence but also in response to genetic events, environment and disease. The effects of the field environment on plant hormone-specific metabolite profiles are largely unknown. Few studies have analyzed useful phenotypes generated by introducing single or multiple gene events alongside the non-engineered wild type control at field scale to determine the robustness of the genetic trait and its modulation in the metabolome as a function of specific agroecosystem environments.

Tomato response to legume cover crop and nitrogen: differing enhancement patterns of fruit yield, photosynthesis and gene expression.

Excessive use of nitrogen (N) in crop production has impacted ecosystems by contaminating soil and water. Management of N in agriculture is therefore of global concern. Sustainable agriculture systems that use leguminous cover crops such as hairy vetch (Vicia villosa Roth) to fix N and enrich soil organic matter by fixing carbon provide an alternative strategy.

Features of a unique intronless cluster of class I small heat shock protein genes in tandem with box C/D snoRNA genes on chromosome 6 in tomato (Solanum lycopersicum).

Physical clustering of genes has been shown in plants; however, little is known about gene clusters that have different functions, particularly those expressed in the tomato fruit. A class I 17.6 small heat shock protein (Sl17.

Genetic engineering to enhance crop-based phytonutrients (nutraceuticals) to alleviate diet-related diseases.

Nutrition studies have provided unambiguous evidence that a number of human health maladies including chronic coronary artery, hypertension, diabetes, osteoporosis, cancer and age- and lifestyle-related diseases are associated with the diet. Several favorable and a few deleterious natural dietary ingredients have been identified that predispose human populations to various genetic and epigenetic based disorders. Media dissemination of this information has greatly raised public awareness of the beneficial effects due to increased consumption of fruit, vegetables and whole grain cereals-foods rich in phytonutrients, protein and fiber.

Polyamines and cellular metabolism in plants: transgenic approaches reveal different responses to diamine putrescine versus higher polyamines spermidine and spermine.

Distribution of biogenic amines-the diamine putrescine (Put), triamine spermidine (Spd), and tetraamine spermine (Spm)-differs between species with Put and Spd being particularly abundant and Spm the least abundant in plant cells. These amines are important for cell viability and their intracellular levels are tightly regulated, which have made it difficult to characterize individual effects of Put, Spd and Spm on plant growth and developmental processes. The recent transgenic intervention and mutational genetics have made it possible to stably alter levels of naturally occurring polyamines and study their biological effects.

Illustrated identification keys to strongylid parasites (Strongylidae: Nematoda) of horses, zebras and asses (Equidae).

The Equidae (the horse, Equus caballus, the ass, Equus asinus, zebras and their hybrids) are hosts to a great variety of nematode parasites, some of which can cause significant morbidity or mortality if individual hosts are untreated. Worldwide the nematode parasites of horses belong to 7 suborders, 12 families, 29 genera and 83 species. The great majority (19 of 29 genera and 64 of 83 species) are members of the family Strongylidae, which includes the most common and pathogenic nematode parasites of horses.

Sucrose non-fermenting 1-related protein kinase 2 (SnRK2): a family of protein kinases involved in hyperosmotic stress signaling.

Our understanding of plant adaptation to abiotic stresses, which include drought, salinity, non-optimal temperatures and poor soil nutrition, is limited, although significant strides have been made in identifying some of the gene players and signaling partners. Several protein kinases get activated in plants in response to osmotic stress and the stress hormone abscisic acid (ABA). Among these is a superfamily of sucrose non-fermenting protein kinase genes (SnRK2).

Overaccumulation of higher polyamines in ripening transgenic tomato fruit revives metabolic memory, upregulates anabolism-related genes, and positively impacts nutritional quality.

Vegetables and fruits are essential components of the human diet as they are sources of vitamins, minerals, and fiber and provide antioxidants that prevent chronic diseases. Our goal is to improve durable nutritional quality of tomato fruit. We developed transgenic tomatoes expressing yeast S-adenosylmethionine decarboxylase (ySAMdc) gene driven by a fruit-specific E8 promoter to investigate the role of polyamines in fruit metabolism.

Phosphorylation of the D1 photosystem II reaction center protein is controlled by an endogenous circadian rhythm.

The light dependence of D1 phosphorylation is unique to higher plants, being constitutive in cyanobacteria and algae. In a photoautotrophic higher plant, Spirodela oligorrhiza, grown in greenhouse conditions under natural diurnal cycles of solar irradiation, the ratio of phosphorylated versus total D1 protein (D1-P index: [D1-P]/[D1] + [D1-P]) of photosystem II is shown to undergo reproducible diurnal oscillation. These oscillations were clearly out of phase with the period of maximum in light intensity.

Redescriptions of Haemonchus mitchelli and Haemonchus okapiae (Nematoda: Trichostrongyloidea) and description of a unique synlophe for the haemonchinae.

In the course of a revision of Haemonchus Cobb, 1898 (Nematoda), commonly referred to as large stomach worms, significant new morphological information was discovered that allows the recognition of 2 species believed for more than 50 yr to be synonymous. Both species, Haemonchus mitchelli Le Roux, 1929, from the eland Taurotragus oryx and other African ruminants and H. okapiae van den Berghe, 1937, from the okapi Okapia johnstoni, have a synlophe of 42 ridges, but the synlophe of H.

Recommended terminology and advances in the systematics of the Cyathostominea (Nematoda: Strongyloidea) of horses.

Terminology for common names for the Tribe Cyathostominea (cyathostomins), and disease caused by the nematodes (cyathostominosis), were recommended to replace the previously used names cyathostomes and cyathostomosis, which are ambiguous, inaccurate or synonymous, by the Third Internal Workshop on the Systematics of Cyathostominea of Horses, held in Stresa, Italy, 28 August 2001. The progress by this international working group at three workshops is reviewed briefly and a list of publications is provided. Included are an annotated checklist by genus and species of 93 species level names and the recognition of 52 species, redescriptions of seven species, and the description of one new species.

Haemonchus horaki n. sp. (Nematoda: Trichostrongyloidea) from the grey rhebuck Pelea capreolus in South Africa.

In the course of a revision of species of Haemonchus Cobb, 1898 (Nematoda), commonly referred to as large stomach worms and significant pathogens of ruminants, a new species was discovered in the grey rhebuck Pelea capreolus, and the bontebok Damaliscus pygarthus, in South Africa. The new species, Haemonchus horaki, was previously reported as a long-spicule form of H. contortus (Rudolphi, 1803) Ransom, 1911.