Isoliquiritigenin, a Strong nod Gene- and Glyceollin Resistance- Inducing Flavonoid from Soybean Root Exudate

Isoflavonoid signal molecules from soybean (Glycine max (L.) Merr.) seed and root exudate induce the transcription of nodulation (nod) genes in Bradyrhizobium japonicum. In this study, a new compound with symbiotic activity was isolated from soybean root exudate. The isolated 2',4',4-trihydroxychalcone (isoliquiritigenin) is characterized by its strong inducing activity for the nod genes of B. japonicum. These genes are already induced at concentrations 1 order of magnitude below those required of the previously described isoflavonoid inducers genistein and daidzein. Isoliquiritigenin is also a potent inducer of glyceollin resistance in B. japonicum, which renders this bacterium insensitive to potentially bactericidal concentrations of glyceollin, the phytoalexin of G. max. No chemotactic effect of isoliquiritigenin was observed. The highly efficient induction of nod genes and glyceollin resistance by isoliquiritigenin suggests the ecological significance of this compound, although it is not a major flavonoid constituent of the soybean root exudate in quantitative terms

Die Mastleistung und Schlachtkörperqualität unterschiedlicher genetischer Schweineherkünfte in konventioneller und ökologischer Haltung

A study was conducted to examine growth and carcass composition of genetically different pigs under conventional and organic conditions. The pig genotypes were Bundeshybridzuchtprogramm (BHZP), Schwäbisch Hällisches Schwein (SH), Angler Sattelschwein (AS), Piétrain x SH (PIxSH), Piétrain x AS (PIxAS), Piétrain x Deutsches Edelschwein (PIxDE) and Duroc x Deutsche Landrasse (DUxDL). A total number of 650 pigs were kept at two test stations. This paper presents results of the test station Neu-Ulrichstein where the genotypes BHZP, SH and PIxSH were tested. Growth and carcass chracteristics of 80 pigs per environment (conventional housing and feeding vs. organic housing and feeding) were analysed using a linear model including the fixed effects of sex, genotype, environment and the interaction of geno-type and environment. Genotype was found to have a significant influence on growth and carcass quality, whereas the BHZP-pigs had a higher daily gain, meat percentage and meat to fat ratio. The influence of the environment was significant for daily gain only, with pigs under conventional conditions gaining 110 g more than pigs under organic conditions. No statistically significant interactions between genotype and environment could be found for this part of the study. With exception of the feed con-version ratio under conventional conditions, the BHZP-pigs showed the best perform-ance and carcass quality in both environments when compared to the PIxSH- and SH- genotypes

Is LEP beam-beam limited at its highest energy?

The operation of LEP at 45.6 GeV was limited by beam-beam effects and the vertical beam-beam parameter xy never exceeded 0.045. At the highest energy of 94.5 GeV, the increased damping allows higher beam-beam parameters xy . Values above 0.07 in the vertical plane averaged over four experiments have been obtained frequently with peak values up to 0.075 in a single experiment. Although the maximum intensity in LEP is presently limited by technical considerations, some observations indicate that the beam-beam limit is close and the question of the maximum possible values can be raised. These observations are shown in this paper and possible consequences are presented. The optimum operation of LEP in the neighbourhood of the beam-beam limit is discussed

A mitofusin-dependent docking ring complex triggers mitochondrial fusion in vitro

International audienceFusion of mitochondrial outer membranes is crucial for proper organelle function and involves large GTPases called mitofusins. The discrete steps that allow mitochondria to attach to one another and merge their outer membranes are unknown. By combining an in vitro mitochondrial fusion assay with electron cryo-tomography (cryo-ET), we visualize the junction between attached mitochondria isolated from Saccharomyces cerevisiae and observe complexes that mediate this attachment. We find that cycles of GTP hydrolysis induce progressive formation of a docking ring structure around extended areas of contact. Further GTP hydrolysis triggers local outer membrane fusion at the periphery of the contact region. These findings unravel key features of mitofusin-dependent fusion of outer membranes and constitute an important advance in our understanding of how mitochondria connect and merge

Alt oder Neu - Welche Rassen passen für die ökologische Schweinefleischerzeugung?

In der ökologischen Schweinemast wird immer wieder über die Eignung alter und moderner Schweinegenotypen sowie die Notwendigkeit eigener Zuchtprogramme diskutiert. Um beide Punkte beantworten zu können, sind Informationen über das Ausmaß möglicher Genotyp- Umwelt-Interaktionen bei relevanten Leistungsmerkmalen notwendig. Daher wurden 682 Schweine von 7 merkmalsdifferenzierten Genotypen auf zwei Leistungsprüfungsanstalten in jeweils ökologischer und konventioneller Haltung auf Merkmale der Mastleistung sowie Schlachtkörper- und Fleischqualität geprüft. Es zeigte sich, dass in der Mastleistung und der Schlachtkörperqualität sowohl die modernen den alten Genotypen als auch die konventionellen den ökologischen Prüfbedingungen überlegen waren. Beim intramuskulären Fettgehalt war es erwartungsgemäß genau umgekehrt. Für sämtliche Merkmale konnten signifikante bis höchstsignifikante Interaktionen zwischen Genotyp und Umwelt nachgewiesen werden. Die Interaktionen wurden vor allem durch Unterschiede zwischen den beiden Prüfumwelten hervorgerufen, die aber nicht zu einer wesentlichen Verschiebung der Rangfolge zwischen den Genotypen innerhalb der Umwelten geführt hat. Daher wird gefolgert, dass für die ökologische Schweinefleischerzeugung keine eigenständigen Zuchtprogramme entwickelt werden müssen, vor allem, wenn Kostenstruktur und Vermarktungsziel bei beiden Systemen im Wesentlichen übereinstimmen, so wie derzeit der Fall

Zur Genotyp-Umwelt-Interaktion in der ökologischen Schweinemast

The suitability of indigenous or modern genotypes for organic conditions and the necessity of a specific organic breeding programme are intensively discussed in the organic pig fattening scene. To clarify both items information about Genotype-Environment-Interaction (GEI) is necessary. Therefore 682 pigs of 7 different genotypes with widely spread protein synthesis capacity were tested for growth performance and carcass quality under conventional and organic environments at two performance testing stations in order to verify GEI. The modern genotypes were superior to the old ones, all genotypes achieved significantly better results within the conventional environment and there were significant interactions between genotype and environment for all criteria of growth performance and carcass quality. The interactions were mainly caused by varying differences between organic and conventional environment within genotypes, but without a shift of the ranking order within environment between genotypes. Hence no special breeding programme is necessary for organic pig fattening under relatively similar marketing systems for conventionally and organically produced pork

Loss of LRPPRC causes ATP synthase deficiency

Defects of the oxidative phosphorylation system, in particular of cytochrome-c oxidase (COX, respiratory chain complex IV), are common causes of Leigh syndrome (LS), which is a rare neurodegenerative disorder with severe progressive neurological symptoms that usually present during infancy or early childhood. The COX-deficient form of LS is commonly caused by mutations in genes encoding COX assembly factors, e.g. SURF1, SCO1, SCO2 or COX10. However, other mutations affecting genes that encode proteins not directly involved in COX assembly can also cause LS. The leucine-rich pentatricopeptide repeat containing protein (LRPPRC) regulates mRNA stability, polyadenylation and coordinates mitochondrial translation. In humans, mutations in Lrpprc cause the French Canadian type of LS. Despite the finding that LRPPRC deficiency affects the stability of most mitochondrial mRNAs, its pathophysiological effect has mainly been attributed to COX deficiency. Surprisingly, we show here that the impaired mitochondrial respiration and reduced ATP production observed in Lrpprc conditional knockout mouse hearts is caused by an ATP synthase deficiency. Furthermore, the appearance of inactive subassembled ATP synthase complexes causes hyperpolarization and increases mitochondrial reactive oxygen species production. Our findings shed important new light on the bioenergetic consequences of the loss of LRPPRC in cardiac mitochondria

Experience with a Low Emittance Optics in LEP

Since start-up in 1998, LEP has operated with a low emittance lattice with a phase advance of 102 deg in the horizontal and 90 deg in the vertical planes. This optics provides a horizontal detuning with amplitude which is small enough to avoid a reduced dynamic aperture in the horizontal plane, a problem experienced in other low emittance lattices. The optics is designed to operate at the highest LEP energies up to and above 100 GeV, as well as at 45.6 GeV (still required to provide Z0s for the calibration of the experiments detectors). The experience gained with this low emittance lattice after one year of operation is presented and its future potential is discussed