An EF-hands protein, centrin-1, is an EGTA-sensitive SUMO-interacting protein in mouse testis

A multifunctional calcium‐binding protein, centrin‐1, is specifically expressed in male germ cells, certain neurons and ciliated cells. We identified centrin‐1 as a protein interacting with SUMO‐2/3 using yeast two‐hybrid screening of a mouse testicular cDNA library. In bead halo assays, the interaction between centrin‐1 and SUMO‐2/3 was reduced in the presence of EGTA and facilitated by the addition of CaCl_2. immunostaining of seminiferous tubules in 35‐day‐old mouse testes revealed that cells in the layer containing spermatogonia showed colocalization of SUMO‐2/3 with centrin‐1 in cytoplasmic spots. Identification of centrin‐1 as the EGTA‐sensitive SUMO‐2/3‐interacting protein indicates the possible role of calcium in modulating the centrin‐1–SUMO‐2/3 interaction and suggests the importance of this interaction in mouse testis. Copyright © 2010 John Wiley & Sons, Ltd.     

Evidence of inbreeding depression on human height

Stature is a classical and highly heritable complex trait, with 80%-90% of variation explained by genetic factors. In recent years, genome-wide association studies (GWAS) have successfully identified many common additive variants influencing human height; however, little attention has been given to the potential role of recessive genetic effects. Here, we investigated genome-wide recessive effects by an analysis of inbreeding depression on adult height in over 35,000 people from 21 different population samples. We found a highly significant inverse association between height and genome-wide homozygosity, equivalent to a height reduction of up to 3 cm in the offspring of first cousins compared with the offspring of unrelated individuals, an effect which remained after controlling for the effects of socio-economic status, an important confounder (χ(2) = 83.89, df = 1; p = 5.2 × 10(-20)). There was, however, a high degree of heterogeneity among populations: whereas the direction of the effect was consistent across most population samples, the effect size differed significantly among populations. It is likely that this reflects true biological heterogeneity: whether or not an effect can be observed will depend on both the variance in homozygosity in the population and the chance inheritance of individual recessive genotypes. These results predict that multiple, rare, recessive variants influence human height. Although this exploratory work focuses on height alone, the methodology developed is generally applicable to heritable quantitative traits (QT), paving the way for an investigation into inbreeding effects, and therefore genetic architecture, on a range of QT of biomedical importance.     

Intracellular diffusion restrictions in isolated cardiomyocytes from rainbow trout

Background  

Restriction of intracellular diffusion of adenine nucleotides has been studied intensively on adult rat cardiomyocytes. However, their cause and role in vivo is still uncertain. Intracellular membrane structures have been suggested to play a role. We therefore chose to study cardiomyocytes from rainbow trout (Oncorhynchus mykiss), which are thinner and have fewer intracellular membrane structures than adult rat cardiomyocytes. Previous studies suggest that trout permeabilized cardiac fibers also have diffusion restrictions. However, results from fibers may be affected by incomplete separation of the cells. This is avoided when studying permeabilized, isolated cardiomyocytes. The aim of this study was to verify the existence of diffusion restrictions in trout cardiomyocytes by comparing ADP-kinetics of mitochondrial respiration in permeabilized fibers, permeabilized cardiomyocytes and isolated mitochondria from rainbow trout heart. Experiments were performed at 10, 15 and 20°C in the absence and presence of creatine.     

Using shared goal setting to improve access and equity: a mixed methods study of the Good Goals intervention in children's occupational therapy

ABSTRACT: BACKGROUND: Access and equity in children's therapy services may be improved by directing clinicians' use of resources toward specific goals that are important to patients. A practice-change intervention (titled 'Good Goals') was designed to achieve this. This study investigated uptake, adoption, and possible effects of at intervention in children's occupational therapy services. METHODS: Mixed methods case studies (n = 3 services, including 46 therapists and 558 children) were conducted. The intervention was delivered over 25 weeks through face-to-face training, team workbooks, and 'tools for change'. Data were collected before, during, and after the intervention on a range of factors using interviews, a focus group, case note analysis, routine data, document analysis, and researchers' observations. RESULTS: Factors related to uptake and adoptions were: mode of intervention delivery, competing demands on therapists' time, and leadership by service manager. Service managers and therapists reported that the intervention: helped therapists establish a shared rationale for clinical decisions; increased clarity in service provision; and improved interactions with families and schools. During the study period, therapists' behaviours changed: identifying goals, odds ratio 2.4 (95% CI 1.5 to 3.8); agreeing goals, 3.5 (2.4 to 5.1); evaluating progress, 2.0 (1.1 to 3.5). Children's LoT decreased by two months [95% CI [MINUS SIGN]8 to +4 months] across the services. Cost per therapist trained ranged from [POUND SIGN]1,003 to [POUND SIGN]1,277, depending upon service size and therapists' salary bands. CONCLUSIONS: Good Goals is a promising quality improvement intervention that can be delivered and adopted in practice and may have benefits. Further research is required to evaluate its: (i) impact on patient outcomes, effectiveness, cost-effectiveness, and (ii) transferability to other clinical contexts.     

Development of chloroplast structure and photosynthetic competence in dark-adapted moss protonemata after exposure to light

Summary Sporelings and protonemata ofCeratodon purpureus were grown in darkness for one to two months. On their exposure to light, starch was observed after 30 minutes but only minor changes occurred in the chloroplast structure during the first hours. After one day in light, the chloroplasts had a structure similar to that of the chloroplasts of light-grown material. The dark-grown material evolved oxygen and assimilated CO₂ readily after exposure to light. Nevertheless, maximization of the photosynthetic rate was not achieved until the second day in light, coinciding with the development of light-type chloroplasts. The ultrastructural localization of photosystems I and II revealed much higher activity of PS I in dark-adapted material than in material grown in light, whereas the activity of PS II appeared to be greater in light-grown material.     

Comparing segmentations by applying randomization techniques

Background  

There exist many segmentation techniques for genomic sequences, and the segmentations can also be based on many different biological features. We show how to evaluate and compare the quality of segmentations obtained by different techniques and alternative biological features.     

The role of metal ions in the activation of arginase.

The role of metal ions as activators of arginase hydrolyzing arginine were studied. The metal ion is assumed to form a complex with arginine and to promote the enzymatic reaction. The activating ability of the metal ion appears to be governed by the chelating ability and/or the coordination numbers which determine whether the metal ion combines with the enzyme or the substrate (or both substrate and enzyme) and factors which influence the configuration of the resulting complexes.