SUMMARY Chronic reactive oxygen species (ROS) production by mitochondria may contribute to the development of insulin resistance, a primary feature of type 2 diabetes. In recent years it has become apparent that ROS generation in response to physiological stimuli such as insulin may also facilitate signaling by reversibly oxidizing and inhibiting protein tyrosine phosphatases (PTPs). Here we report that mice lacking one of the key enzymes involved in the elimination of physiological ROS, glutathione peroxidase 1 (Gpx1), were protected from high fat diet-induced insulin resistance. The increased insulin sensitivity in Gpx1−/− mice was attributed to insulin-induced phosphatidylinositol-3-kinase/Akt signaling and glucose uptake in muscle and could be reversed by the anti-oxidant N-acetylcysteine. Increased insulin signaling correlated with enhanced oxidation of the PTP family member PTEN, which terminates signals generated by phosphatidylinositol-3-kinase. These studies provide causal evidence for the enhancement of insulin signaling by ROS in vivo.

Several Lathyrus species and in particular Lathyrus sativus (grass pea) have great agronomic potential as grain and forage legume, especially in drought conditions. Grass pea is rightly considered as one of the most promising sources of calories and protein for the vast and expanding populations of drought-prone and marginal areas of Asia and Africa. It is virtually the only species that can yield high protein food and feed under these conditions. It is superior in yield, protein value, nitrogen fixation, and drought, flood and salinity tolerance than other legume crops. Lathyrus species have a considerable potential in crop rotation, improving soil physical conditions; reducing the amount of disease and weed populations, with the overall reduction of production costs. Grass pea was already in use in Neolithic times, and presently is considered as a model crop for sustainable agriculture. As a result of the little breeding effort invested in it compared to other legumes, grass pea cultivation has shown a regressive pattern in many areas in recent decades. This is due to variable yield caused by sensitivity to diseases and stress factors and above all, to the presence of the neurotoxin β-N-oxalyl-L-α,β-diaminopropionic acid (β-ODAP), increasing the danger of genetic erosion. However, both L. sativus and L. cicera are gaining interest as grain legume crops in Mediterranean-type environments and production is increasing in Ethiopia, China, Australia and several European countries.This paper reviews research work on Lathyrus breeding focusing mainly on biotic and abiotic resistance improvement, and lists current developments in biotechnologies to identify challenges for Lathyrus improvement in the future.

Results suggest that time-distinct gene induction of TNF-alpha, furin, IL-1beta and matrilysin may be involved in UV-induced cellular responses, but not for TACE. In general, mRNA induction was dose dependent at some time points post-irradiation, but not throughout the whole time course tested. Our results show that quantitative real-time PCR is a useful tool in the analysis of quantitative changes of mRNA levels in cultured HaCaT cells after UV exposure.

A linkage map of the Lathyrus sativus genome was constructed using 92 backcross individuals derived from a cross between an accession resistant (ATC 80878) to ascochyta blight caused by Mycosphaerella pinodes and a susceptible accession (ATC 80407). A total of 64 markers were mapped on the backcross population, including 47 RAPD, seven sequence-tagged microsatellite site and 13 STS/CAPS markers. The map comprised nine linkage groups, covered a map distance of 803.1 cM, and the average spacing between markers was 15.8 cM. Quantitative trait loci (QTL) associated with ascochyta blight resistance were detected using single-point analysis and simple and composite interval mapping. The backcross population was evaluated for stem resistance in temperature-controlled growth room trials. One significant QTL, QTL1, was located on linkage group 1 and explained 12% of the phenotypic variation in the backcross population. A second suggestive QTL, QTL2, was detected on linkage group 2 and accounted for 9% of the trait variation. The L. sativus R-QTL regions detected may be targeted for future intergenus transfer of the trait into accessions of the closely related species Pisum sativum.

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Ten isolates of Ascochyta lentis derived from a single conidiospore were crossed with each other in order to induce the teleomorph Didymella lentis. Mature pseudothecia and viable ascospores were produced from crosses between compatible mating types. Isolates AL27 and AL36 were determined to be MAT1-1, and isolates AL4, AL41, and USA4 to be MAT1-2. This study identified isolate RB6 to be MAT1-1, not MAT1-2 as previously reported. The inheritance of virulence in A. lentis to the lentil cultivar Northfield was studied by crossing a Northfield-attacking isolate (AL4) with an avirulent isolate (AL36). The F1 progeny segregated in a 3:1 ratio for high virulence/low virulence, suggesting that virulence of A. lentis to Northfield may be controlled by 2 independently segregating genes, operating in mutual epistasis.

Three Lathyrus sativus accessions were screened for their reaction to Mycosphaerella pinodes infection. Accession ATC 80878 displayed the lowest percentage stem lesion values (%SL) and was significantly more resistant to M. pinodes than ATC 80407 and ATC 80053. Accession ATC 80407 was the most susceptible, displaying the severest disease symptoms. A backcross and an F2 population were generated using accessions ATC 80878 and ATC 80407 as the resistant and susceptible parents, respectively. The backcross and F2 progeny segregated in a 3 : 1 and 7 : 9 ratio, respectively, for resistance/susceptibility, using the 99% confidence intervals for the means of the parental controls in each assay to determine the point of discontinuity. The segregation data from both populations fitted a Mendelian segregation model that suggested that resistance in the L. sativus accession ATC 80878 may be controlled by 2 independently segregating genes, operating in a complementary epistatic manner.

A simple device for quantitative urine collection from male sheep kept in metabolic cages is described. The device consists of a modified funnel-urinal fixed to the body of the animal. The urinal is made of: a soft plastic foil internal funnel that collects the urine; an external strong nylon tissue funnel to protect from mechanical damage; a plastic ring joining both funnels and ties fixing the funnels to the body; a connector joining the funnels with soft plastic flexible tube draining the excreted urine into the collection container. The device performed satisfactorily in numerous balance type experiments. An advantage of the described method is that it uses a simple, easily made device and prevents urine loss during collection. The urine is free of contamination with faeces and feed.