Arabidopsis ABSCISIC ACID INSENSEITIVE3 (ABI3), FUSCA3 (FUS3) and LEAFY COTYLEDON1 (LEC1) encode key transcription factors that control seed maturation events, including seed storage protein (SSP) accumulation. Although lec1 mutations are known to down-regulate SSP gene expression as the fus3 or abi3 mutation does, the mechanisms by which LEC1 regulates SSP gene expression are largely unknown compared with the mechanisms utilized by FUS3 or ABI3. We expressed LEC1 ectopically in transgenic plants using an artificial dexamethasone (Dex) induction system. The ectopic expression of LEC1 also resulted in the induction of FUS3 and ABI3 expression, which preceded the induction of SSP expression. The expression of FUS3 and ABI3 was found to be down-regulated in developing siliques of the lec1 mutant. Furthermore, the levels of ectopic SSP induction by LEC1 were greatly or moderately reduced in transgenic plants with an abi3 or fus3 mutant background, respectively. LEC1-induced ectopic expression of the At1g62290 aspartic protease gene, which was identified to be regulated preferentially by FUS3, was more severely affected in the fus3 mutant than in the abi3 mutant. From these data, we suggest that LEC1 controls the expression of the SSP genes in a hierarchical manner, which involves ABI3 and FUS3.

The key transcription factors that control seed maturation, ABSCISIC ACID INSENSITIVE3 (ABI3) and FUSCA3 (FUS3), share homologous DNA-binding domains. Regulation of seed storage protein genes At2S3 and CRC by ABI3 and FUS3 was investigated using transgenic plants in which ABI3 and FUS3 could be ectopically induced by steroid hormones. Like ABI3, the presence of FUS3 led to expression of At2S3 and CRC in vegetative tissues. FUS3-mediated induction of CRC was completely dependent on exogenous abscisic acid (ABA), while At2S3 was weakly induced without ABA but strongly enhanced with ABA. This ABA dependency of FUS3-induced CRC and At2S3 expression was similar to that observed for ABI3. However, kinetic analysis revealed distinctions between the mechanisms of ABA-dependent CRC regulation by FUS3 or ABI3, and between target genes. While At2S3 activation by FUS3 was rapid, CRC induction by FUS3 in the presence of ABA, and by ABA followed by the presence of FUS3, took a significantly longer time (24-36 h). This suggested the involvement of an indirect mechanism requiring the ABA- and FUS3-dependent synthesis of intermediate regulatory factor(s). A chimeric protein composed of the FUS3 B3 domain, and a heterologous activation domain and nuclear localization signal exhibited a tight coupling with ABA regulation as observed for wild-type FUS3. Simultaneous induction of FUS3 and ABI3 did not result in the synergistic activation of CRC and At2S3. Based on these results, similarities and differences in the mechanisms of seed storage protein gene regulation by FUS3 and ABI3 are discussed.

Aim:  The major objective of the present study was to clarify genetic relationship of isolates of Edwardsiella ictaluri in Japan, which was first found from ayu Plecoglossus altivelis in Japanese rivers in 2007. Methods and Results:  Ten isolates of Edw. ictaluri in 2007–2008 from ayu and the 1 isolate from bagrid catfish Pelteobagrus nudiceps in Japan were subjected to amplified‐fragment length polymorphism (AFLP) analysis. The strains isolated from catfish in United States (ATCC strains) or Indonesia were used as reference strains. The AFLP profiles were all the same among the isolates from Japan, while the polymorphic DNA bands were observed among the strains from United States or Indonesia. The isolates from Japan and Indonesia constituted a genogroup different from the ATCC strains on a dendrogram constructed from the AFLP profiles. Conclusion:  No DNA polymorphisms were found among Japanese Edw. ictaluri isolates. Significance and Impact of the Study:  A single clonality of the Edw. ictaluri isolates in Japan suggests the single source of the organism, and the infection in ayu is in the early stage of epidemics.

There are four atoll states in the world: The Republic of Kiribati, the Maldives, the Republic of the Marshall Islands (RMI), and Tuvalu. These countries are comprised entirely of low-lying land approximately 2 m above sea level. The Intergovernmental Panel on Climate Change (IPCC) has recognized that atoll countries are highly vulnerable to rising sea levels due to climate change. This study aimed to clarify the relative advantages and disadvantages of possible alternatives compared to the present livelihoods of the Marshallese in their home country. We also attempted to identify the best plausible option, using few sets of possible value judgements over the evaluation criteria. The following four alternatives were examined in this study: (i) migration to the developed world, (ii) migration to other island states, (iii) land reclamation and raising, and (iv) development of floating platforms. To evaluate the performance of the four alternatives, we selected 16 criteria representing the societal conditions that would result from each alternative. The performance of each alternative per criterion was rated from 1 to 5 by a literature survey, interviews with researchers who worked on the livelihood of Marshallese immigrants in the U.S. states of Arkansas, Hawaii, and Oregon, and interviews with people knowledgeable about the behavior of the Marshallese both in their home country and in the United States as immigrants. The “migration to the developed world” alternative proved the best choice, followed by “developing floating platforms,” “land reclamation and raising,” and “migration to other island states.” We also found that “migration to the developed world” offered the most change to immigrants, while the alternative of “land reclamation and raising” resulted in the smallest change. The magnitude of anticipated change should be considered. We employed the Analytic Hierarchy Process (AHP) to experimentally evaluate four alternatives in an integrated manner and about three cases were “all the criteria are equally important,” “social environment is more important,” and “personal environment is more important.” With AHP, the “migration to the developed world” alternative yielded the highest point for all three cases examined. Notably, climate migrants do not suddenly emerge, because climate change is a slow-onset process. The Marshallese should make wise use of the available lead time to prepare for migration in the future.