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The aggregated transfer factor (Tag) is commonly used to represent the actual transfer of radiocesium from soil to wild edible plants, but the values have shown substantial variation since the Fukushima nuclear accident. To elucidate the factors causing this variation, we investigated the effects of spatial scale and vertical 137Cs distribution in the soil on the variation of Tag-137Cs values for one of the most severely contaminated wild edible plants, Eleutherococcus sciadophylloides Franch. et Sav. (Koshiabura). The variation in Tag-137Cs values was not reduced by direct measurement of 137Cs deposition in soil samples from the Koshiabura habitat, as a substitute for using spatially averaged airborne survey data at the administrative district scale. The 137Cs activity concentration in Koshiabura buds showed a significant positive correlation with the 137Cs inventories only in the organic horizon of soil from the Koshiabura habitat. The ratio of 137Cs inventories in the organic horizon to the total 137Cs deposition in soil exhibited substantial variation, especially in broad-leaved deciduous forests that Koshiabura primarily inhabits. This variation may be the cause of the wide range of Tag-137Cs values observed in Koshiabura buds when calculated from the total 137Cs deposition in soil. [ABSTRACT FROM AUTHOR]

We obtained the aggregated transfer factor (Tag) for 10 common edible wild plant species (four perennial spermatophytes, bamboo shoot, two tree species, and three perennial pteridophytes) in northeastern Japan. Measurement of Tag was carried out in 2012–2019 and we also used publicly available data for 2012–2019: food monitoring data and total deposition data from an airborne survey. The Tag obtained from actual measurements agreed well with Tag values calculated from the publicly available data. The sampling locations were only identified at the municipal level and uncertainty of the deposition for the publicly available data, and thus Tag values showed substantial variation. The Tag of the perennial spermatophytes, including bamboo shoot, and perennial pteridophytes showed single exponential decline with effective half-lives of approximately 2 years, whereas those of tree species did not show distinct temporal change. These results imply that data since 2014 are applicable for Tag estimation for long-term potential ingestion dose in the future to the public because of the slow decline. The calculated Tag values of all species for 2014–2019 ranged from 6.1 × 10−5 to 5.2 × 10−3 m2/kg-fresh mass. The maximum Tag value was observed for the tree koshiabura (Chengiopanax sciadophylloides) and the minimum value was observed for the perennial spermatophyte giant butterbur (Petasites japonica). Tree species showed higher Tag than spermatophyte and pteridophyte perennials. [ABSTRACT FROM AUTHOR]

Aurora kinase (AUR) is a well-known mitotic serine/threonine kinase that regulates centromere formation, chromosome segregation, and cytokinesis in eukaryotes. In addition to regulating mitotic events, AUR has been shown to regulate protein dynamics during interphase in animal cells. In contrast, there has been no identification and characterization of substrates and/or interacting proteins during interphase in plants. The Arabidopsis thaliana genome encodes three AUR paralogues, AtAUR1, AtAUR2, and AtAUR3. Among them, AtAUR1 and AtAUR2 are considered to function redundantly. Here, we confirmed that both AtAUR1 and AtAUR3 are localized in the nucleus and cytoplasm during interphase, suggesting that they have functions during interphase. To identify novel interacting proteins, we used AlphaScreen to target 580 transcription factors (TFs) that are mainly functional during interphase, using recombinant A. thaliana TFs and AtAUR1 or AtAUR3. We found 133 and 32 TFs had high potential for interaction with AtAUR1 and AtAUR3, respectively. The highly AtAUR-interacting TFs were involved in various biological processes, suggesting the functions of the AtAURs during interphase. We found that AtAUR1 and AtAUR3 showed similar interaction affinity to almost all TFs. However, in some cases, the interaction affinity differed substantially between the two AtAUR homologues. These results suggest that AtAUR1 and AtAUR3 have both redundant and distinct functions through interactions with TFs. In addition, database analysis revealed that most of the highly AtAUR-interacting TFs contained a detectable phosphopeptide that was consistent with the consensus motifs for human AURs, suggesting that these TFs are substrates of the AtAURs. The AtAURs phosphorylated several highly interacting TFs in the AlphaScreen in vitro. Overall, in line with the regulation of TFs through interaction, our results indicate the possibility of phosphoregulation of several TFs by the AtAURs (280/300). [ABSTRACT FROM AUTHOR]

After two decades operation of the initial environmental specimen banking, a new program, Environmental Time Capsule Program, started in 2002 as a government-supported long-term program to construct a firm scientific basis for various environmental research studies. The program consists of long-term environmental specimen banking activity and specimen collection of endangered wildlife and is based on cryogenic sample preservation facility called Environmental Time Capsule building, which completed construction in 2004. After 9 years of extensive research, research focuses have been selected and the program was reorganized to the environmental sample collection part and endangered wildlife collection part in 2011. Due to huge environmental disaster caused by the Great East Japan earthquake and the tsunami as well as subsequent nuclear power plant accident at Fukushima, a new sampling and monitoring program started at affected areas in collaboration with the reorganized environmental sample collection and archiving program. Outlines of the quality assurance and quality control (QA/QC) activities in the program and future perspective under related international activities, particularly Stockholm Convention, are reported. [ABSTRACT FROM AUTHOR]

Objectives: Lead concentrations in whole blood (BPb) of Japanese children were measured to obtain insight into the sources of variation and to estimate health risk. Methods: Blood samples were taken from 352 children (aged 1-14 years) at pediatric clinics/hospitals in 3 regions of Japan (Tokyo, Shizuoka, and Osaka) during 2005-2006 (Shizuoka only) and 2008-2010 (3 regions), and BPb was measured by inductively coupled plasma mass spectrometry after acid digestion. Results: Geometric mean BPb of the 352 children was 1.07 μg/dL, among the lowest in the world. Based on this result, the probability of exceeding BPb 10 μg/dL, the action level proposed by the US Centers for Disease Control and Prevention, in general Japanese children was estimated to be negligible. There was a significant negative correlation between BPb and age, while sex difference was not significant. BPb was significantly lower in subjects in Tokyo than in the other two regions. Age-adjusted mean BPb was significantly higher in children with a family member who smoked in their presence than in those who did not have such a family member, indicating that passive smoking had a significant effect on BPb. Conclusions: Health risk of lead exposure is minimal in Japanese children. To lower the exposure level further, reduction of passive smoking is suggested as one of the effective measures. [ABSTRACT FROM AUTHOR]