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

Lingua-Franca Future Self-Guides: How Do They Predict Shame?

Second-language (L2) future self-guides have been studied in relation to emotions. What remains unclear relates to the norms of L2 selves. Future selves with a lingua-franca (LF) ideology, which emphasizes shared responsibility, might make a difference in emotions. By developing questionnaire items to measure LF future selves, the current study investigated how LF selves predicted shame. Two hundred and fifty-seven undergraduates learning English in Japan participated by completing the questionnaire consisting of 38 items to measure LF selves, L2 selves, and L2 shame. Exploratory factor analysis (n = 257) conducted on the LF self items and subsequent confirmatory factor analysis performed on another sample of representation (n = 123) revealed three factors: ideal LF self/own, ideal LF self/others, and ought-to LF self. Partial correlation analyses between each two L2 or LF selves did not reveal a significant unique correlation between ideal L2 self and ought-to L2 self/own (r = .09). Rather, the seeming association between the two L2 selves was mediated by the LF selves. Hierarchical multiple regression analysis revealed that ideal LF self/own changed the prediction of shame in the direction of relieving L2 shame. The results suggest that cultivating an LF ideology may support the well-being of English learners. The data uploaded are the raw data of the survey consisting of one used for exploratory factor analysis, correlation analysis, and hierarchical multiple regression analysis (n = 257) and one used for confirmatory factor analysis (n = 123).THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV