Transcript and metabolite analysis in Trincadeira cultivar reveals novel information regarding the dynamics of grape ripening

BACKGROUND

Grapes (Vitis vinifera L.) are economically the most important fruit crop worldwide. However, the complexity of molecular and biochemical events that lead to the onset of ripening of nonclimacteric fruits is not fully understood which is further complicated in grapes due to seasonal and cultivar specific variation. The Portuguese wine variety Trincadeira gives rise to high quality wines but presents extremely irregular berry ripening among seasons probably due to high susceptibility to abiotic and biotic stresses.

RESULTS

Ripening of Trincadeira grapes was studied taking into account the transcriptional and metabolic profilings complemented with biochemical data. The mRNA expression profiles of four time points spanning developmental stages from pea size green berries, through véraison and mature berries (EL 32, EL 34, EL 35 and EL 36) and in two seasons (2007 and 2008) were compared using the Affymetrix GrapeGen® genome array containing 23096 probesets corresponding to 18726 unique sequences. Over 50% of these probesets were significantly differentially expressed (1.5 fold) between at least two developmental stages. A common set of modulated transcripts corresponding to 5877 unigenes indicates the activation of common pathways between years despite the irregular development of Trincadeira grapes. These unigenes were assigned to the functional categories of "metabolism", "development", "cellular process", "diverse/miscellanenous functions", "regulation overview", "response to stimulus, stress", "signaling", "transport overview", "xenoprotein, transposable element" and "unknown". Quantitative RT-PCR validated microarrays results being carried out for eight selected genes and five developmental stages (EL 32, EL 34, EL 35, EL 36 and EL 38). Metabolic profiling using 1H NMR spectroscopy associated to two-dimensional techniques showed the importance of metabolites related to oxidative stress response, amino acid and sugar metabolism as well as secondary metabolism. These results were integrated with transcriptional profiling obtained using genome array to provide new information regarding the network of events leading to grape ripening.

CONCLUSIONS

Altogether the data obtained provides the most extensive survey obtained so far for gene expression and metabolites accumulated during grape ripening. Moreover, it highlighted information obtained in a poorly known variety exhibiting particular characteristics that may be cultivar specific or dependent upon climatic conditions. Several genes were identified that had not been previously reported in the context of grape ripening namely genes involved in carbohydrate and amino acid metabolisms as well as in growth regulators; metabolism, epigenetic factors and signaling pathways. Some of these genes were annotated as receptors, transcription factors, and kinases and constitute good candidates for functional analysis in order to establish a model for ripening control of a non-climacteric fruit.

ε-Acetamidocaproic acid pharmacokinetics in rats with gastric ulcer or small bowel inflammation

The pharmacokinetics of ϵ-acetamidocaproic acid (AACA) were evaluated after the intravenous and oral administration of an antiulcer agent, zinc acexamate (ZAC) at a dose of 20 mg kg⁻¹ (ion pairing between zinc and AACA) in rats with indomethacin-induced acute gastric ulcer (IAGU) or indomethacin-induced small bowel inflammation (ISBI). In IAGU rats, the area under the curves (AUCs) of AACA were significantly smaller after both the intravenous (551 versus 1270 μg min ml⁻¹) and oral (397 versus 562 μg min ml⁻¹) administration of ZAC than controls, possible due to the significantly faster CL(R) of AACA. In ISBI rats, however, the AUCs of AACA were comparable with controls after both the intravenous and oral administration of ZAC. In IAGU rats, the significantly smaller AUCs of AACA were due to the significantly faster CL(R) (due to the decreased urinary pH by indomethacin treatment) than controls. AACA has a basic secondary amine group. On the other hand, the comparable AUCs of AACA in ISBI rats were due to the comparable CL(R)s between ISBI and control rats. AACA was excreted in the urine via active renal tubular secretion in all rats studied.

Production of live foals via intracytoplasmic injection of lyophilized sperm and sperm extract in the horse

Work with lyophilized sperm helps delineate the factors required for successful fertilization. We investigated the use of lyophilized sperm in equine embryo production. In Experiment 1, sperm DNA fragmentation index was not affected by three freeze/thaw or lyophilization cycles. In Experiment 2, oocytes injected with lyophilized sperm or with sperm from a treatment in which lyophilized sperm were suspended in sperm cytoplasmic extract (SE) yielded blastocyst development rates of 0 and 28% respectively (P<0.05). In Experiment 3, blastocyst development rate was 6–11% after injection of sperm lyophilized from fresh or frozen–thawed semen, suspended in SE. In Experiment 4, sperm lyophilized 3.5 months or 1 week previously, suspended in SE, yielded similar blastocyst rates (6 and 3% respectively). Rates of normal pregnancy after transfer were 7/10 and 5/7 for embryos from control and lyophilized sperm treatments respectively. Three pregnancies from the lyophilized sperm treatments were not terminated, resulting in two healthy foals. Parentage testing determined that one foal originated from the lyophilized sperm; the other was the offspring of the stallion providing the sperm extract. Further testing indicated that two of five additional embryos in the lyophilized sperm treatment originated from the stallion providing the sperm extract. We conclude that both lyophilized stallion sperm and stallion sperm processed by multiple unprotected freeze–thaw cycles (as for sperm extract) can support production of viable foals. To the best of our knowledge, this is the first report on production of live offspring by fertilization with lyophilized sperm in a non-laboratory animal species.

Metabolic fingerprinting reveals differences between shoots of wild and cultivated carrot (Daucus carota L.) and suggests maternal inheritance or wild trait dominance in hybrids

Differences between the metabolic content of cultivars and their related wild species not only have implications for breeding and food quality, but also for the increasingly studied area of crop to wild introgression. Wild and cultivated western carrots belong to the same outcrossing species and hybridize under natural conditions. The metabolic fingerprinting of Dutch wild carrot and of western orange carrot cultivar shoots using (1)H NMR showed only quantitative differences in chemical content, indicating relatively low divergence after domestication. Main differences reside in the primary metabolite content and in the concentrations of chlorogenic acid and feruloyl quinic acid in the shoots of the different carrot types. Wild×cultivar hybrids cannot be distinguished from wild plants based on the metabolome, suggesting maternal, maternal environment, or dominance effects, and indicating high hybrid fitness in wild conditions. Considering these similarities, introgression is a real possibility in carrots, but understanding its consequences would require further studies using backcrosses in a multiple environments.

Comprehensive review on herbal medicine for energy intake suppression

The obesity drug development is present not a bright and successful story. So far, drugs reported to be effective, either from synthetic or natural sources, mostly stimulated controversy because of serious adverse effects, which ended with stopping clinical trials or even withdrawal from the market. However, obesity and its comorbidities have become rapidly a major problem in both developed and developing countries. This has encouraged pharmaceutical companies and academia to keep on struggling on developing novel effective but safe obesity drugs, and on characterizing novel obesity drug targets. From existing scientific work on obesity drug discovery and commercial slimming preparations, compounds originating from nature, especially from plants, seem to be the first choice. Traditional belief that herbal medicine is safer than synthetic ones is one of the classical arguments, although scientifically this is not always true (e.g. ban on Ephedra). But in general, it has been widely acknowledged that a plant compound, with its unique scaffolds and rich diversity is an unlimited source of novel lead compounds. This paper aims to summarize all works focused on screening plant materials by targeting important pathways related to energy intake regulation, either by in vivo or in vitro experiments.

An overview of NMR-based metabolomics to identify secondary plant compounds involved in host plant resistance

Secondary metabolites provide a potential source for the generation of host plant resistance and development of biopesticides. This is especially important in view of the rapid and vast spread of agricultural and horticultural pests worldwide. Multiple pests control tactics in the framework of an integrated pest management (IPM) programme are necessary. One important strategy of IPM is the use of chemical host plant resistance. Up to now the study of chemical host plant resistance has, for technical reasons, been restricted to the identification of single compounds applying specific chemical analyses adapted to the compound in question. In biological processes however, usually more than one compound is involved. Metabolomics allows the simultaneous detection of a wide range of compounds, providing an immediate image of the metabolome of a plant. One of the most universally used metabolomic approaches comprises nuclear magnetic resonance spectroscopy (NMR). It has been NMR which has been applied as a proof of principle to show that metabolomics can constitute a major advancement in the study of host plant resistance. Here we give an overview on the application of NMR to identify candidate compounds for host plant resistance. We focus on host plant resistance to western flower thrips (Frankliniella occidentalis) which has been used as a model for different plant species.