Ranging behaviour of feral cattle (Bos taurus) in Doñana National Park, S.W. Spain

The cattle of Doñana (139 individuals in four social groups in 1989) have lived under free-ranging conditions for centuries. Their ranging behaviour was analysed during a three-year period. A total of 17,603 locations corresponding to 247 different animals allowed both for the estimation of global and seasonal home ranges of individuals and social groups and for the comparison of movement patterns. Cattle ranging behaviour was not affected by human interference, and was shown to be regulated by a complex interaction of environment, individual and social factors. Habitat structure and seasonal fluctuations in abundance and distribution of resources determined general patterns of ranging behaviour: the greater the concentration of resources, the smaller the home ranges of individuals and social groups. These patterns were modified at an individual level by the sex of the animal and its reproductive status if male. Social influences on ranging behaviour were important because these implied the segregation of home ranges among dominant bulls and among social groups. As a result, there was a great variability in space use and home-range behaviour.     

Loose binding of testicular mitochondrial ATPase to the inner membrane

Rat testis mitochondrial ATPase was not inhibited by oligomycin at pH 7.5. It was inhibited only at higher alkaline pH's, and showed a lower sensitivity both to oligomycin and N,N′-dicyclohexylcarbodiimide and a higher one to efrapeptin. In submitochondrial particles, testis ATPase was only slightly inhibited by oligomycin, ossamycin, and efrapeptin. The possibility of a loose binding of F₁ to the membrane was supported by its recovery from the supernatant of the submitochondrial particles. Furthermore, by electron microscopy, after hypoosmotic shock and negative staining of the mitochondrial preparations, most of the inner mitochondrial membranes showed only a few “knobs” or none at all. The capacity of the testis mitochondrial preparation to produce ATP was tested and compared to that from liver. ATP synthetase/ATPase activity ratio was $\text{30}\text{1}$ in liver mitochondria, whereas in the testis it was $\text{3}\text{1}$. In spite of this large difference, at least part of the testis ATPase must be firmly bound to the membrane, since it is able to form ATP. The rest seems to be loosely bound and its functional significance is still unknown.     

Sesquiterpene lactones from Viguiera species

Viguiera eriophora yielded the sesquiterpene lactones erioflorin, acetylerioflorin and 17,18-dehydroviguiepinin, which was correlated with tetrahyd     

Thymidylate synthetase: Studies on the peptide containing covalently bound 5-fluoro-2′-deoxyuridylate and 5,10-methylenetetrahydrofolate

Studies are reported on the FdUMP-CH₂-H₄ folate-peptide obtained upon proteolysis of the complex formed from thymidylate synthetase, FdUMP and 5,10-CH₂-H₄folate. Contrary to a previous report from this laboratory, the peptide does contain a cysteine residue. The sequence of the largest peptide obtained is Ala-Leu-Pro-Pro-(His,Cys)-Thr. Quantitative modification of the histidine residue with the Pauly reagent indicates that imidazole is not directly linked to the nucleotide. The stability of the peptide indicates the covalent bond to the cofactor involves its 5-nitrogen; from this, it may be concluded that the reactive form of the cofactor is the 5-iminium ion.     

Predicted residue–residue contacts can help the scoring of 3D models

During the 7th Critical Assessment of Protein Structure Prediction (CASP7) experiment, it was suggested that the real value of predicted residue–residue contacts might lie in the scoring of 3D model structures. Here, we have carried out a detailed reassessment of the contact predictions made during the recent CASP8 experiment to determine whether predicted contacts might aid in the selection of close‐to‐native structures or be a useful tool for scoring 3D structural models. We used the contacts predicted by the CASP8 residue–residue contact prediction groups to select models for each target domain submitted to the experiment. We found that the information contained in the predicted residue–residue contacts would probably have helped in the selection of 3D models in the free modeling regime and over the harder comparative modeling targets. Indeed, in many cases, the models selected using just the predicted contacts had better GDT‐TS scores than all but the best 3D prediction groups. Despite the well‐known low accuracy of residue–residue contact predictions, it is clear that the predictive power of contacts can be useful in 3D model prediction strategies. Proteins 2010. © 2010 Wiley‐Liss, Inc.     

Spin label electron paramagnetic resonance study in thylakoid membranes from a new herbicide-resistant D1 mutant from soybean cell cultures deficient in fatty acid desaturation

We examined the effect of fluvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, on the production of hydroxyl radical (*OH) generation via nitric oxide synthase (NOS) activation by an in vivo microdialysis technique. The microdialysis probe was implanted in the left ventricular myocardium of anesthetized rats and tissue was perfused with Ringer's solution through the microdialysis probe at a rate of 1 microl/min. Sodium salicylate in Ringer's solution (0.5 nmol/microl/min) was infused directly through a microdialysis probe to detect the generation of *OH. Induction of [K(+)](o) (70 mM) or tyramine (1 mM), significantly increased the formation of *OH trapped as 2,3-dihydroxybenzoic acid (DHBA). The application of N(G)-nitro-L-arginine methyl ester (L-NAME), a NOS inhibitor, significantly decreased the K(+) depolarization-induced *OH formation, but the effect of tyramine significantly increased the level of 2,3-DHBA. When fluvastatin (100 microM), an inhibitor of low-density lipoprotein (LDL) oxidation, was administered to L-NAME-pretreated animals, both KCl and tyramine failed to increase the level of 2,3-DHBA formation. The effect of fluvastatin may be unrelated to K(+) depolarization-induced *OH generation. To examine the effect of fluvastatin on ischemic/reperfused rat myocardium, the heart was subjected to myocardial ischemia for 15 min by occlusion of the left anterior descending coronary artery (LAD). When the heart was reperfused, a marked elevation of the level of 2,3-DHBA was observed. However, in the presence of fluvastatin (100 microM), the elevation of 2,3-DHBA was not observed in ischemia/reperfused rat heart. Fluvastatin, orally at a dose of 3 mg/kg/day for 4 weeks, significantly blunted the rise of serum creatine phosphokinase and improved the electrocardiogram 2 h after coronary occlusion. These results suggest that fluvastatin is associated with a cardioprotective effect due to the suppression of noradrenaline-induced *OH generation by inhibiting LDL oxidation in the heart.     

The Influence of Hunting on Antipredator Behavior in Central African Monkeys and Duikers

Many animals can adjust their behavioral strategies to reduce predation risk. We investigated whether rain forest monkeys and duikers alter their antipredatory behavior in response to hunting by humans in southwestern Gabon. We compared monkey and duiker responses to human observers in an area where hunting is prohibited, to those in a nearby area where hunting pressure is moderate but spatially variable. The results of our study indicate that monkeys become more secretive when hunted, commencing alarm calls only when at a certain distance (typically > 50 m) from humans. We found no difference in monkey group size between hunted and no-hunting areas. In no-hunting areas, duikers often freeze in response to approaching observers, but in hunted areas they abandon this strategy and rapidly flee from humans. Duikers also whistle more often in areas where they are hunted frequently. Our findings have at least two important implications. First, behavioral observations of monkeys and duikers may be useful in gauging local hunting intensity in African rain forests. Second, duiker densities are likely to be overestimated in hunted areas, where they more readily flee and whistle, and underestimated in no-hunting areas, where they rely on freezing behavior to avoid detection. Because behavioral adaptations to hunting vary both among species and localities, these differences should be considered when attempting to derive population-density estimates for forest wildlife.     

Multiple factors influence adventitious rooting in carnation (<Emphasis Type="Italic">Dianthus caryophyllus</Emphasis> L.) stem cuttings

Efficient propagation of uniform starting material is a critical requirement for mass production of most ornamental plants, including carnation. For some elite cultivars, the production of young plantlets is limited by poor adventitious root formation from stem cuttings. We previously characterized the molecular signature during adventitious rooting in two carnation cultivars, 2101-02 MFR and 2003 R 8, which were selected because of their contrasting rooting performance. To determine additional factors that contribute to the differences observed in adventitious rooting during the commercial scaling-up of this species, we characterized rooting performance and endogenous hormone levels in stem cuttings of these two cultivars during one production season. We found that stem cutting production declined during the harvest season in a cultivar-dependent manner. In addition, the initiation of adventitious roots in the stem cutting base depended on its endogenous auxin and cytokinin levels at harvest time, while their subsequent growth and development was mainly influenced by the physiological status of the mother plant at harvest time and of the stem cutting during the rooting process.