Expression of a gene encoding a ribosomal p40 protein and identification of an active promoter site

The promoter of a gene encoding a ribosome-associated protein of 40 kDa from Arabidopsis thaliana (A-p40) was sequenced and the expression of the gene studied. A-p40 was expressed in the same organs and with the same variations as the eukaryotic elongation factor 1 (eEF1A), another gene coding for a protein involved in translation Arabidopsis plants transformed with a -glucuronidase (GUS) gene driven by the A-p40 promoter confirm that A-p40 is expressed in actively dividing and growing cells. eEF1A promoter-GUS fusions have the same pattern of expression. Comparison of cis-acting elements from A-p40 and eEF1A revealed some common elements. A-p40 promoter deletions and transient gene expression in transfected Arabidopsis protopasts allowed the identification of trap40, a cis-acting element regulating gene expression. Gel retardation experiments indicate that eEF1A and A-p40 are regulated by different cis-acting elements. The role of such elements is discussed.     

Hand preferences in chimpanzees (Pan troglodytes), bonobos (Pan paniscus), and orangutans (Pongo pygmaeus) in food-reaching and other daily activities

We observed 36 captive great apes [31 chimpanzees (Pan troglodytes),2 bonobos (Pan paniscus), and3 orangutans (Pongo pygmaeus)]reaching for items of food and engaging in other spontaneous behaviors. We consider circumstantial factors that could influence the preferred choice of one hand or the other. Most of the subjects (81%) showed a significant hand preference in food reaching that is consistent in directionality with the hand preferences that they showed during other spontaneous behaviors. The results show that the postural adjustment required when carrying out an action seems to influence directly the expression of manual laterality in individuals. Moreover, the results indicate the possible existence of a relationship between maturational factors and persistence in directionality of hand preferences.     

Peroxidase isoenzymes in the defense response of Capsicum annuum to Phytophthora capsici

Quantitative and qualitative changes in isoperoxidase patterns from stems of three cultivars of pepper ( Capsicum annuum L.). one susceptible, one intermediate and one resistant, were found upon inoculation with Phytophthora capsici using a decapitation method. The peroxidase activity was determined in the intercellular fluid as well as in the cytosolic fraction of the necrotic, healthy and intermediate zones of stems of the three cultivars, 6 days after inoculation. In the intercellular fluid, peroxidase activity of the susceptible cv. Yolo Wonder increased somewhat from 4.7 (healthy zone) to 12.9 (intermediate zone) μmol mg⁻¹ protein min⁻¹, whereas in the intermediate cv. Americano, the peroxidase activity decreased from 123 (healthy zone) to 78 (intermediate zone) μmol mg⁻¹ protein min⁻¹. The most dramatic increase (5.7 to 662 μmol mg⁻¹ protein min⁻¹) in intercellular peroxidase activity was found in the resistant cv. Smith-5. This, in conjunction with the appearance of an additional acidic isoperoxidase (pI 4.4) specific for the cv. Smith-5, could be the reason for the resistance of this cultivar against the fungus attack. The release of peroxidase into the intercellular space as a defense reaction was confirmed by histochemical analysis, showing that peroxidase activity occurred in the intercellular spaces of those stems of the resistant cultivar that had not yet been invaded by the fungus, but was detected neither in the other cultivars nor in the intercellular spaces of such stems of the intermediate and susceptible cultivars that contained growing mycelium of P. capsici. The lack of staining in the intercellular spaces of the susceptible cultivars could be attributed to their low content in peroxidase.     

EFFECTS OF ARSENATE ON GROWTH AND PHOSPHORUS METABOLISM OF PHYTOPLANKTON1,2

The response to arsenate in growth and phosphate uptake by five algae in culture varied considerably. The growth rates of Melosira granulata var. angustissima O. Müll, and Ochromonas vallesiaca Chodat were depressed by 1 μM arsenale. Chlamydomonas reinhardtii Dang. required 10 μM for the same degree of depression, while the growth rules of Cryptomonas eroasa Ehr. and Anabaena variabilis Kütz. were unaffeted up to 100 μM. However, following depletion of phosphate, cultures of the later two algae began to die at the higher concentrations of arsenale tested. Growth of C. reinhardtii in the presence of 35 μM arsenate resulted in characteristics of P deficiency. Comparison of rates of photosynthesis, respiration, and phosphate uptake between cultures of C. reinhardtii which had grown in the presence and absence of arsenate showed little evidence after 16 doublings that it had adapted to arsenale.     

A PAS reaction in erythrocytes of formalin-fixed tissue treated with Holt's hypertonic gum sucrose

Summary When paraffin sections of mouse and rat kidney, liver and spleen were fixed in a formalin-type fixative overnight, then preserved in Holt's hypertonic gum-sucrose solution, erythrocytes stained strongly by the McManus periodic acid-Schiff method. The same tissues processed without gum-sucrose did not exhibit such positive staining of red blood cells. Tissues treated with the individual gum-sucrose components, a solution of gum arabic or of sucrose, gave positive staining of erythrocytes only after gum arabic. Powdered gum arabic but not sucrose crystals stained positively. The erythrocyte reaction in formalinfixed tissue treated with gum-sucrose is therefore related to the presence of gum arabic in Holt's solution. Opposing results were encountered with two non-formalin fixatives, glutaraldehyde and acetone, in that staining was consistently positive throughout in the former and consistently negative in the latter, regardless of gum-sucrose treatment.     

Posttranslational Processing of Brain Actin

Abstract: Two short-lived isoforms of actin, named δ- and ε-actin, have been detected in brain extracts from rats labeled in vivo with [³⁵S]methionine. These two molecular species have PI values slightly more basic than β- and γ-actin, the stable isoforms of the protein found in brain tissue. Under the appropriate incubation conditions δ- and ε-actin, synthesized in vivo , can be converted in vitro into β- and γ-actin. This posttranslational processing of δ- and ε-actin requires acetyl coenzyme A, suggesting that an acetylation step, presumably of the NH₂-terminal end, is involved in the transformation of these proteins into β- and γ-actin.     

Evaluating evolutionary pressures and phylogenetic signal in earthworms: a case study – the number of typhlosole lamellae in Hormogastridae (Annelida,Oligochaeta)

Rarely have phylogenetic comparative methods been used to study the correlation between phenotypic traits and environmental variables in invertebrates. With the widespread convergence and conservativeness of the morphological characters used in earthworms, these comparative methods could be useful to improve our understanding of their evolution and systematics. One of the most prominent morphological characters in the family Hormogastridae, endemic to Mediterranean areas, is their multilamellar typhlosole, traditionally thought to be an adaptation to soils poor in nutrients. We tested the correlation of body size and soil characteristics with the number of typhlosole lamellae through a phylogenetic generalized least squares (PGLS) analysis. An ultrametric phylogenetic hypothesis was built with a 2580‐bp DNA sequence from 90 populations, used in combination with three morphological and 11 soil variables. The best‐supported model, based on the Akaike information criterion, was obtained by optimizing the parameters lambda (λ), kappa (κ), and delta (δ). The phylogenetic signal was strong for the number of typhlosole lamellae and average body weight, and was lower for soil variables. Increasing body weight appeared to be the main evolutionary pressure behind the increase in the number of typhlosole lamellae, with soil texture and soil richness having a weaker but significant effect. Information on the evolutionary rate of the number of typhlosole lamellae suggested that the early evolution of this character could have strongly shaped its variability, as is found in an adaptive radiation. This work highlights the importance of implementing the phylogenetic comparative method to test evolutionary hypotheses in invertebrate taxa.     

Functional and Morphological Correlates in the Drosophila LRRK2 loss-of-function Model of Parkinson’s Disease: Drug Effects of Withania somnifera (Dunal) Administration

The common fruit fly Drosophila melanogaster (Dm) is a simple animal species that contributed significantly to the development of neurobiology whose leucine-rich repeat kinase 2 mutants (LRRK2) loss-of-function in the WD40 domain represent a very interesting tool to look into physiopathology of Parkinson’s disease (PD). Accordingly, LRRK2 Dm have also the potential to contribute to reveal innovative therapeutic approaches to its treatment. Withania somnifera Dunal, a plant that grows spontaneously also in Mediterranean regions, is known in folk medicine for its anti-inflammatory and protective properties against neurodegeneration. The aim of this study was to evaluate the neuroprotective effects of its standardized root methanolic extract (Wse) on the LRRK2 loss-of-function Dm model of PD. To this end mutant and wild type (WT) flies were administered Wse, through diet, at different concentrations as larvae and adults (L⁺/A⁺) or as adults (L^-/A⁺) only. LRRK2 mutants have a significantly reduced lifespan and compromised motor function and mitochondrial morphology compared to WT flies 1% Wse-enriched diet, administered to Dm LRRK2 as L^-/A⁺and improved a) locomotor activity b) muscle electrophysiological response to stimuli and also c) protected against mitochondria degeneration. In contrast, the administration of Wse to Dm LRRK2 as L⁺/A⁺, no matter at which concentration, worsened lifespan and determined the appearance of increased endosomal activity in the thoracic ganglia. These results, while confirming that the LRRK2 loss-of-function in the WD40 domain represents a valid model of PD, reveal that under appropriate concentrations Wse can be usefully employed to counteract some deficits associated with the disease. However, a careful assessment of the risks, likely related to the impaired endosomal activity, is required.