The effects of environment on Arctica islandica shell formation and architecture

Mollusks record valuable information in their hard parts that reflect ambient environmental conditions. For this reason, shells can serve as excellent archives to reconstruct past climate and environmental variability. However, animal physiology and biomineralization, which are often poorly understood, can make the decoding of environmental signals a challenging task. Many of the routinely used shell-based proxies are sensitive to multiple different environmental and physiological variables. Therefore, the identification and interpretation of individual environmental signals (e.g., water temperature) often is particularly difficult. Additional proxies not influenced by multiple environmental variables or animal physiology would be a great asset in the field of paleoclimatology. The aim of this study is to investigate the potential use of structural properties of Arctica islandica shells as an environmental proxy. A total of 11 specimens were analyzed to study if changes of the microstructural organization of this marine bivalve are related to environmental conditions. In order to limit the interference of multiple parameters, the samples were cultured under controlled conditions. Three specimens presented here were grown at two different water temperatures (10 and 15 °C) for multiple weeks and exposed only to ambient food conditions. An additional eight specimens were reared under three different dietary regimes. Shell material was analyzed with two techniques; (1) confocal Raman microscopy (CRM) was used to quantify changes of the orientation of microstructural units and pigment distribution, and (2) scanning electron microscopy (SEM) was used to detect changes in microstructural organization. Our results indicate that A. islandica microstructure is not sensitive to changes in the food source and, likely, shell pigment are not altered by diet. However, seawater temperature had a statistically significant effect on the orientation of the biomineral. Although additional work is required, the results presented here suggest that the crystallographic orientation of biomineral units of A. islandica may serve as an alternative and independent proxy for seawater temperature

La inoculación de Azospirillum brasilense mejora la calidad de las plántulas de un mezquite (Prosopis juliflora)

Inoculation of mycorrhizal fungi and rhizobacteria in plants can improve their growth and physiological status, which could be particularly important for agricultural and forestry plants used for the revegetation of arid areas. Prosopis juliflora is a forest pioneer species that is drought resistant and has multiple uses (fodder, shade and shelter for livestock; timber and firewood, live fences and windbreaks in agroforestry systems). Azospirillum brasilense is a rhizobacterium that improves the growth of many agricultural crops. The hypothesis of this study was that P. juliflora seedlings produced in the nursery can respond positively to inoculation with A. brasilense CECT 590. Five months after inoculation, we examined the growth, water relations (osmotic potential at full turgor, osmotic potential at zero turgor, and the modulus of elasticity at full turgor), and concentration and content of macronutrients (N, P, K, Ca and Mg) in the seedlings. Subsequently, a trial was conducted to analyse root growth potential. A. brasilense CECT 590 inoculation caused an osmotic adjustment in P. juliflora seedlings but decreased the elasticity of the cell walls. Inoculation with A. brasilense CECT 590 significantly improved plant growth due in part to an increase of N concentration in the seedlings. A. brasilense CECT 590 inoculation also caused an increase in the root growth potential. The increased growth of P. juliflora seedlings inoculated with A. brasilense was probably caused by more than one mechanism. Inoculation with A. brasilense at the nursery may be a suitable technique for producing improved seedling material for restoration purposes.La inoculación de hongos de micorrizacion y rizobacterias en las plantas puede mejorar su crecimiento y calidad fisiológica, especialmente en plantas agrícolas y forestales empleadas para la regeneración de zonas áridas. Prosopis juliflora es una especie forestal pionera, resistente a la sequía, y de usos múltiples (forraje, sombra y cobijo para el ganado, madera y leña, cercas vivas y cortinas cortavientos en sistemas agroforestales). Azospirillum brasilense es una rizobacteria que mejora el crecimiento de muchos cultivos agrícolas. La hipótesis de este estudio fue que las plántulas de P. juliflora producidas en vivero pueden responder positivamente a la inoculación con A. brasilense CECT 590. Cinco meses después desde la inoculación, se analizó el crecimiento, relaciones hídricas (potencial osmótico en saturación, potencial osmótico en el punto de pérdida de turgencia, y módulo de elasticidad a total turgor), concentración y contenido de macronutrientes (N, P, K, Ca y Mg) en las plántulas. Posteriormente se realizó un ensayo para analizar el Potencial de Crecimiento Radical. La inoculación de A. brasilense CECT 590 causó un ajuste osmótico de las plántulas de P. juliflora, pero disminuyó la elasticidad de las paredes celulares. A. brasilense CECT 590 mejoró significativamente el crecimiento de la planta, debido en parte al incremento de la concentración de N en las plántulas. La inoculación con A. brasilense CECT 590 también causó un incremento del potencial de crecimiento radical. El incremento del crecimiento en las plántulas de P. juliflora inoculadas con A. brasilense fue probablemente debido a más de un mecanismo. La inoculación con A. brasilense en vivero puede ser una técnica adecuada para la producción de material de plántulas mejorado con fines de restauración

The pentameric nucleoplasmin fold is present in Drosophila FKBP39 and a large number of chromatin-related proteins.

Nucleoplasmin is a histone chaperone that consists of a pentameric N-terminal domain and an unstructured C-terminal tail. The pentameric core domain, a doughnut-like structure with a central pore, is only found in the nucleoplasmin family. Here, we report the first structure of a nucleoplasmin-like domain (NPL) from the unrelated Drosophila protein, FKBP39, and we present evidence that this protein associates with chromatin. Furthermore, we show that two other chromatin proteins, Arabidopsis thaliana histone deacetylase type 2 (HD2) and Saccharomyces cerevisiae Fpr4, share the NPL fold and form pentamers, or a dimer of pentamers in the case of HD2. Thus, we propose a new family of proteins that share the pentameric nucleoplasmin-like NPL domain and are found in protists, fungi, plants and animals.We are grateful to Gunter Stier for providing the vector; Michael Nilges, Oleg Fedorov, Benjamin Bardiaux, Stefanie Hartmann and Wolfgang Rieping for helpful discussions; and Daniel Nietlispach for NMR expertise. We thank Renato Paro for generously providing us with an anti-FKBP39 antibody. We would like to thank the Wellcome Trust for financial support (grant 082010/Z/07/Z). V.T.F. and E.D.L. acknowledge support from Engineering and Physical Sciences Research Council under grants GR/R99393/01 and EP/C015452/1 for the creation of the Deuteration Laboratory platform operating within the Grenoble Partnership for Structural Biology. V.T.F. also acknowledges support from the European Union under contract RII3-CT-2003-505925. J.B.A. acknowledges the provision of a postdoctoral fellowship held at Keele University. M.R.P. and D.M.G. were supported by the Medical Research Council and Cancer Research UK grants to D.M.G. A.A.W. is a recipient of a Wellcome Trust Fellowship092441/Z/10/Z. J.D. and M.D. were supported by the Harmonia 5 Grant 2013/10/M/NZ2/00298 from the Polish National Science Center. The authors would like to thank the Institut Laue-Langevin (ILL), the European Synchrotron Radiation Facility (ESRF) and the European Molecular Biology Laboratory Hamburg outstation (EMBL-HH) for the provision of beamtime and access to the experimental facilities of D22, ID14eh3 and X33 respectively. We would also like to thank the local contacts at all the facilities for providing assistance in using the beam lines.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.jmb.2015.03.01

The Pentameric Nucleoplasmin Fold Is Present in Drosophila FKBP39 and a Large Number of Chromatin-Related Proteins

Nucleoplasmin is a histone chaperone that consists of a pentameric N-terminal domain and an unstructured C-terminal tail. The pentameric core domain, a doughnut-like structure with a central pore, is only found in the nucleoplasmin family. Here, we report the first structure of a nucleoplasmin-like domain (NPL) from the unrelated Drosophila protein, FKBP39, and we present evidence that this protein associates with chromatin. Furthermore, we show that two other chromatin proteins, Arabidopsis thaliana histone deacetylase type 2 (HD2) and Saccharomyces cerevisiae Fpr4, share the NPL fold and form pentamers, or a dimer of pentamers in the case of HD2. Thus, we propose a new family of proteins that share the pentameric nucleoplasmin-like NPL domain and are found in protists, fungi, plants and animals

The relative age effect on physical fitness in preschool children

The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ ¿ = 0.383; F10, 5996 = 369.64; p < 0.001, ¿p 2 = 0.381) and of quarter (Wilks’ ¿ = 0.874; F15, 8276.6 = 27.67; p < 0.001; ¿p 2 = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers

Influence of muscle fitness test performance on metabolic risk factors among adolescent girls

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to examine the association between muscular fitness (MF), assessed by 2 components of Fitnessgram test battery, the Curl-Up and Push-Ups tests and the metabolic risk score among adolescent girls.</p> <p>Methods</p> <p>A total of 229 girls (aged 12-15 years old) comprised the sample of this study. Anthropometric data (height, body mass, waist circumference) were collected. Body mass index (BMI) was also calculated. Muscular strength was assessed taking into account the tests that comprised the FITNESSGRAM test battery, i.e. the curl-up and the push-up. Participants were then categorized in one of 3 categories according the number of tests in which they accomplished the scores that allow them to be classified in health or above health zone. The blood pressure [BP], fasting total cholesterol [TC], low density lipoprotein-cholesterol [LDL-C], high density lipoprotein-cholesterol [HDL-C], triglycerides [TG], glucose, and a metabolic risk score (MRS) were also examined. Physical Activity Index (PAI) was obtained by questionnaire.</p> <p>Results</p> <p>Higher compliance with health-zone criteria (good in the 2 tests), adjusted for age and maturation, were positive and significantly (p ≤ 0.05) associated with height (r = 0.19) and PAI (r = 0.21), while a significant but negative association was found for BMI (r = -0.12); WC (r = -0.19); TC (r = -0.16); TG (r = -0.16); LDL (r = -0.16) and MRS (r = -0.16). Logistic regression showed that who were assigned to MF fittest group were less likely (OR = 0.27; p = 0.003) to be classified overweight/obese and less likely (OR = 0.26; p = 0.03) to be classified as having MRS. This last association was also found for those whom only performed 1 test under the health zone (OR = 0.23; p = 0.02).</p> <p>Conclusions</p> <p>Our data showed that low strength test performance was associated with increased risk for obesity and metabolic risk in adolescent girls even after adjustment for age and maturation.</p

Natural humoral immune response to ribosomal P0 protein in colorectal cancer patients

Tumor associated antigens are useful in colorectal cancer (CRC) management. The ribosomal P proteins (P0, P1, P2) play an important role in protein synthesis and tumor formation. The immunogenicity of the ribosomal P0 protein in head and neck, in breast and prostate cancer patients and the overexpression of the carboxyl-terminal P0 epitope (C-22 P0) in some tumors were reported

Klf15 Is Critical for the Development and Differentiation of Drosophila Nephrocytes

Insect nephrocytes are highly endocytic scavenger cells that represent the only invertebrate model for the study of human kidney podocytes. Despite their importance, nephrocyte development is largely uncharacterised. This work tested whether the insect ortholog of mammalian Kidney Krüppel-Like Factor (Klf15), a transcription factor required for mammalian podocyte differentiation, was required for insect nephrocyte development. It was found that expression of Drosophila Klf15 (dKlf15, previously known as Bteb2) was restricted to the only two nephrocyte populations in Drosophila, the garland cells and pericardial nephrocytes. Loss of dKlf15 function led to attrition of both nephrocyte populations and sensitised larvae to the xenotoxin silver nitrate. Although pericardial nephrocytes in dKlf15 loss of function mutants were specified during embryogenesis, they failed to express the slit diaphragm gene sticks and stones and did not form slit diaphragms. Conditional silencing of dKlf15 in adults led to reduced surface expression of the endocytic receptor Amnionless and loss of in vivo scavenger function. Over-expression of dKlf15 increased nephrocyte numbers and rescued age-dependent decline in nephrocyte function. The data place dKlf15 upstream of sns and Amnionless in a nephrocyte-restricted differentiation pathway and suggest dKlf15 expression is both necessary and sufficient to sustain nephrocyte differentiation. These findings explain the physiological relevance of dKlf15 in Drosophila and imply that the role of KLF15 in human podocytes is evolutionarily conserve