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Perceived threat from outgroups is a consistent social-environmental antecedent of intergroup bias (i.e. prejudice, ingroup favoritism). The serotonin transporter gene polymorphism (5-HTTLPR) has been associated with individual variations in sensitivity to context, particularly stressful and threatening situations. Here, we examined how 5-HTTLPR and environmental factors signaling potential outgroup threat dynamically interact to shape intergroup bias. Across two studies, we provide novel evidence for a gene–environment interaction on the acquisition of intergroup bias and prejudice. Greater exposure to signals of outgroup threat, such as negative prior contact with outgroups and perceived danger from the social environment, were more predictive of intergroup bias among participants possessing at least one short allele (vs two long alleles) of 5-HTTLPR. Furthermore, this gene x environment interaction was observed for biases directed at diverse ethnic and arbitrarily-defined outgroups across measures reflecting intergroup biases in evaluation and discriminatory behavior. These findings reveal a candidate genetic mechanism for the acquisition of intergroup bias, and suggest that intergroup bias is dually inherited and transmitted through the interplay of social (i.e. contextual cues of outgroup threat) and biological mechanisms (i.e. genetic sensitivity toward threatening contexts) that regulate perceived intergroup threats. [ABSTRACT FROM PUBLISHER]

Long-term cultural experiences influence neural response to one's own and friend's faces. The present study investigated whether an individual's culturally specific pattern of neural activity to faces can be modulated by temporary access to other cultural frameworks using a self-construal priming paradigm. Event-related potentials were recorded from British and Chinese adults during judgments of orientations of one's own and friend's faces after they were primed with independent and interdependent self-construals. We found that an early frontal negative activity at 220–340 ms (the anterior N2) differentiated between one's own and friend's faces in both cultural groups. Most remarkably, for British participants, priming an interdependent self-construal reduced the default anterior N2 to their own faces. For Chinese participants, however, priming an independent self-construal suppressed the default anterior N2 to their friend's faces. These findings indicate fast modulations of culturally specific neural responses induced by temporary access to other cultural frameworks. [ABSTRACT FROM AUTHOR]

Nitrate reallocation to plant roots occurs frequently under adverse conditions and was recently characterized to be actively regulated by Nitrate Transporter!.8 (NRT1.8) in Arabidopsis (Arabidopsis thaliana) and implicated as a common response to stresses. However, the underlying mechanisms remain largely to be determined. In this study, characterization of NRT1.5, a xylem nitrate-loading transporter, showed that the mRNA level of NRT1.5 is down-regulated by salt, drought, and cadmium treatments. Functional disruption of NRT1.5 enhanced tolerance to salt, drought, and cadmium stresses. Further analyses showed that nitrate, as well as Na+ and Cd2+ levels, were significantly increased in nrtl.5 roots. Important genes including Na+ /H+ exchangerl, Salt overly sensitivel, Pyrroline-5-carboxylate synthasel, Responsive to desiccation29A, Phytochelatin synthasel, and NRT1.8 in stress response pathways are steadily up-regulated in nrtl.5 mutant plants. Interestingly, altered accumulation of metabolites, including proline and malondialdehyde, was also observed in nrtl.5 plants. These data suggest that NRT1.5 is involved in nitrate allocation to roots and the consequent tolerance to several stresses, in a mechanism probably shared with NRT1.8. [ABSTRACT FROM AUTHOR]

Much of our dietary uptake of heavy metals is through the consumption of plants. A long-sought strategy to reduce chronic exposure to heavy metals is to develop plant varieties with reduced accumulation in edible tissues. Here, we describe that the fission yeast (Schizosaccharomyces pombe) phytochelatin (PC)-cadmium (Cd) transporter SpHMT1 produced in Arabidopsis (Arabidopsis thaliana) was localized to tonoplast, and enhanced tolerance to and accumulation of Cd2+, copper, arsenic, and zinc. The action of SpHMT1 requires PC substrates, and failed to confer Cd2+ tolerance and accumulation when glutathione and PC synthesis was blocked by L-buthionine sulfoximine, or only PC synthesis is blocked in the cad1-3 mutant, which is deficient in PC synthase. SpHMT1 expression enhanced vacuolar Cd2+ accumulahon m wild-type Columbia-0, but not in cad1-3, where only approximately 35% of the Cd2+ in protoplasts was localized in vacuoles, in contrast to the near 100% found in wild-type vacuoles and approximately 25% in those of cad2-1 that synthesizes very low amounts of glutathione and PCs. Interestingly, constitutive SpHMT1 expression delayed root-to-shoot metal transport, and root-targeted expression confirmed that roots can serve as a sink to reduce metal contents in shoots and seeds. These findings suggest that SpHMT1 function requires PCs in Arabidopsis, and it is feasible to promote food safety by engineering plants using SpHMT1 to decrease metal accumulation in edible tissues. [ABSTRACT FROM AUTHOR]

Nitrate reallocation to plant roots occurs frequently under adverse conditions and was recently characterized to be actively regulated by Nitrate Transporter!.8 (NRT1.8) in Arabidopsis (Arabidopsis thaliana) and implicated as a common response to stresses. However, the underlying mechanisms remain largely to be determined. In this study, characterization of NRT1.5, a xylem nitrate-loading transporter, showed that the mRNA level of NRT1.5 is down-regulated by salt, drought, and cadmium treatments. Functional disruption of NRT1.5 enhanced tolerance to salt, drought, and cadmium stresses. Further analyses showed that nitrate, as well as Na+ and Cd2+ levels, were significantly increased in nrtl.5 roots. Important genes including Na+ /H+ exchangerl, Salt overly sensitivel, Pyrroline-5-carboxylate synthasel, Responsive to desiccation29A, Phytochelatin synthasel, and NRT1.8 in stress response pathways are steadily up-regulated in nrtl.5 mutant plants. Interestingly, altered accumulation of metabolites, including proline and malondialdehyde, was also observed in nrtl.5 plants. These data suggest that NRT1.5 is involved in nitrate allocation to roots and the consequent tolerance to several stresses, in a mechanism probably shared with NRT1.8. [ABSTRACT FROM AUTHOR]