Metal accumulation in tobacco expressing Arabidopsis halleri metal hyperaccumulation gene depends on external supply

Engineering enhanced transport of zinc to the aerial parts of plants is a major goal in bio-fortification. In Arabidopsis halleri, high constitutive expression of the AhHMA4 gene encoding a metal pump of the P1B-ATPase family is necessary for both Zn hyperaccumulation and the full extent of Zn and Cd hypertolerance that are characteristic of this species. In this study, an AhHMA4 cDNA was introduced into N. tabacum var. Xanthi for expression under the control of its endogenous A. halleri promoter known to confer high and cell-type specific expression levels in both A. halleri and the non-hyperaccumulator A. thaliana. The transgene was expressed at similar levels in both roots and shoots upon long-term exposure to low Zn, control, and increased Zn concentrations. A down-regulation of AhHMA4 transcript levels was detected with 10 μM Zn resupply to tobacco plants cultivated in low Zn concentrations. In general, a transcriptional regulation of AhHMA4 in tobacco contrasted with the constitutively high expression previously observed in A. halleri. Differences in root/shoot partitioning of Zn and Cd between transgenic lines and the wild type were strongly dependent on metal concentrations in the hydroponic medium. Under low Zn conditions, an increased Zn accumulation in the upper leaves in the AhHMA4-expressing lines was detected. Moreover, transgenic plants exposed to cadmium accumulated less metal than the wild type. Both modifications of zinc and cadmium accumulation are noteworthy outcomes from the biofortification perspective and healthy food production. Expression of AhHMA4 may be useful in crops grown on soils poor in Zn

Sensory Symptom Profiles and Co-Morbidities in Painful Radiculopathy

Painful radiculopathies (RAD) and classical neuropathic pain syndromes (painful diabetic polyneuropathy, postherpetic neuralgia) show differences how the patients express their sensory perceptions. Furthermore, several clinical trials with neuropathic pain medications failed in painful radiculopathy. Epidemiological and clinical data of 2094 patients with painful radiculopathy were collected within a cross sectional survey (painDETECT) to describe demographic data and co-morbidities and to detect characteristic sensory abnormalities in patients with RAD and compare them with other neuropathic pain syndromes. Common co-morbidities in neuropathic pain (depression, sleep disturbance, anxiety) do not differ considerably between the three conditions. Compared to other neuropathic pain syndromes touch-evoked allodynia and thermal hyperalgesia are relatively uncommon in RAD. One distinct sensory symptom pattern (sensory profile), i.e., severe painful attacks and pressure induced pain in combination with mild spontaneous pain, mild mechanical allodynia and thermal hyperalgesia, was found to be characteristic for RAD. Despite similarities in sensory symptoms there are two important differences between RAD and other neuropathic pain disorders: (1) The paucity of mechanical allodynia and thermal hyperalgesia might be explained by the fact that the site of the nerve lesion in RAD is often located proximal to the dorsal root ganglion. (2) The distinct sensory profile found in RAD might be explained by compression-induced ectopic discharges from a dorsal root and not necessarily by nerve damage. These differences in pathogenesis might explain why medications effective in DPN and PHN failed to demonstrate efficacy in RAD

Distinct Actin and Lipid Binding Sites in Ysc84 Are Required during Early Stages of Yeast Endocytosis

During endocytosis in S. cerevisiae, actin polymerization is proposed to provide the driving force for invagination against the effects of turgor pressure. In previous studies, Ysc84 was demonstrated to bind actin through a conserved N-terminal domain. However, full length Ysc84 could only bind actin when its C-terminal SH3 domain also bound to the yeast WASP homologue Las17. Live cell-imaging has revealed that Ysc84 localizes to endocytic sites after Las17/WASP but before other known actin binding proteins, suggesting it is likely to function at an early stage of membrane invagination. While there are homologues of Ysc84 in other organisms, including its human homologue SH3yl-1, little is known of its mode of interaction with actin or how this interaction affects actin filament dynamics. Here we identify key residues involved both in Ysc84 actin and lipid binding, and demonstrate that its actin binding activity is negatively regulated by PI(4,5)P2. Ysc84 mutants defective in their lipid or actin-binding interaction were characterized in vivo. The abilities of Ysc84 to bind Las17 through its C-terminal SH3 domain, or to actin and lipid through the N-terminal domain were all shown to be essential in order to rescue temperature sensitive growth in a strain requiring YSC84 expression. Live cell imaging in strains with fluorescently tagged endocytic reporter proteins revealed distinct phenotypes for the mutants indicating the importance of these interactions for regulating key stages of endocytosis

The DREEM, part 1: measurement of the educational environment in an osteopathy teaching program

Background Measurement of the educational environment has become more common in health professional education programs. Information gained from these investigations can be used to implement and measure changes to the curricula, educational delivery and the physical environment. A number of questionnaires exist to measure the educational environment, and the most commonly utilised of these is the Dundee Ready Educational Environment Measure (DREEM). Methods The DREEM was administered to students in all year levels of the osteopathy program at Victoria University (VU), Melbourne, Australia. Students also completed a demographic survey. Inferential and correlational statistics were employed to investigate the educational environment based on the scores obtained from the DREEM. Results A response rate of 90% was achieved. The mean total DREEM score was 135.37 (+/- 19.33) with the scores ranging from 72 to 179. Some subscales and items demonstrated differences for gender, clinical phase, age and whether the student was in receipt of a government allowance. Conclusions There are a number of areas in the program that are performing well, and some aspects that could be improved. Overall students rated the VU osteopathy program as more positive than negative. The information obtained in the present study has identified areas for improvement and will enable the program leaders to facilitate changes. It will also provide other educational institutions with data on which they can make comparisons with their own programs

Fusicoccin Counteracts the Toxic Effect of Cadmium on the Growth of Maize Coleoptile Segments

The effects of cadmium (Cd; 0.1–1000 μM) and fusicoccin (FC) on growth, Cd2+ content, and membrane potential (Em) in maize coleoptile segments were studied. In addition, the Em changes and accumulation of Cd and calcium (Ca) in coleoptile segments treated with Cd2+ combined with 1 μM FC or 30 mM tetraethylammonium (TEA) chloride (K+-channel blocker) were also determined. In this study, the effects of Ca2+-channel blockers [lanthanum (La) and verapamil (Ver)] on growth and content of Cd2+ and Ca2+ in coleoptile segments were also investigated. It was found that Cd at high concentrations (100 and 1000 μM) significantly inhibited endogenous growth of coleoptile segments and simultaneously measured proton extrusion. FC combined with Cd2+ counteracted the toxic effect of Cd2+ on endogenous growth and significantly decreased Cd2+ content (not the case for Cd2+ at the highest concentration) in coleoptile segments. Addition of Cd to the control medium caused depolarization of Em, the extent of which was dependent on Cd concentration and time of treatment with Cd2+. Hyperpolarization of Em induced by FC was suppressed in the presence of Cd2+ at 1000 μM but not Cd2+ at 100 μM. It was also found that treatment of maize coleoptile segments with 30 mM TEA chloride caused hyperpolarization of Em and decreased Cd2+ content in coleoptile segments, suggesting that, in the same way as for FC, accumulation of Cd2+ was dependent on plasma membrane (PM) hyperpolarization. Similar to FC, TEA chloride also decreased Ca2+ content in coleoptile segments. La and Ver combined with Cd2+ (100 μM) significantly decreased Cd content in maize coleoptile segments, but only La completely abolished the toxic effect of Cd2+ on endogenous growth and growth in the presence of FC. Taken together, these results suggest that the mechanism by which FC counteracts the toxic effect of Cd2+ (except at 1000 μM Cd2+) on the growth of maize coleoptile segments involves both stimulation of PM H+-ATPase activity by FC as well as Cd2+-permeable, voltage-dependent Ca channels, which are blocked by FC and TEA chloride-induced PM hyperpolarization

Comprehensive analysis of the ATM, CHEK2 and ERBB2 genes in relation to breast tumour characteristics and survival: a population-based case-control and follow-up study

BACKGROUND: Mutations in the ataxia-telangiectasia mutated (ATM) and checkpoint kinase 2 (CHEK2) genes and amplification of the v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 2 (ERBB2) gene have been suggested to have an important role in breast cancer aetiology. However, whether common variation in these genes has a role in the development of breast cancer or breast cancer survival in humans is still not clear. METHODS: We performed a comprehensive haplotype analysis of the ATM, CHEK2 and ERBB2 genes in a Swedish population-based study, which included 1,579 breast cancer cases and 1,516 controls. We followed the cases for 8.5 years, on average, and retrieved information on the date and cause of death during that period from the nationwide Swedish causes of death registry. We selected seven haplotype-tagging SNPs (tagSNPs) in the ATM gene, six tagSNPs in the CHEK2 gene and seven tagSNPs in the ERBB2 gene that predicted both haplotypic and single locus variations in the respective genes with R(2 )values ≥ 0.8. These tagSNPs were genotyped in the complete set of cases and controls. We computed expected haplotype dosages of the tagSNP haplotypes and included the dosages as explanatory variables in Cox proportional hazards or logistic regression models. RESULTS: We found no association between any genetic variation in the ATM, CHEK2 or ERBB2 genes and breast cancer survival or the risk of developing tumours with certain characteristics. CONCLUSION: Our results indicate that common variants in the ATM, CHEK2 or ERBB2 genes are not involved in modifying breast cancer survival or the risk of tumour-characteristic-defined breast cancer

Current status of the multinational Arabidopsis community

The multinational Arabidopsis research community is highly collaborative and over the past thirty years these activities have been documented by the Multinational Arabidopsis Steering Committee (MASC). Here, we (a) highlight recent research advances made with the reference plant Arabidopsis thaliana; (b) provide summaries from recent reports submitted by MASC subcommittees, projects and resources associated with MASC and from MASC country representatives; and (c) initiate a call for ideas and foci for the “fourth decadal roadmap,” which will advise and coordinate the global activities of the Arabidopsis research community