Zebrafish pou2, which encodes a class V POU transcription factor considered to be an orthologue of mouse Oct-3/4, has been implicated by mutant analysis in dorsoventral (DV) patterning, gastrulation, and endoderm formation in early embryos and later in the regionalization of the neural plate. A series of gain-of-function experiments were conducted in the present study to directly reveal the roles pou2 plays in embryogenesis. We first revealed that injecting low-dose wild-type pou2 mRNA ventralizes embryos. Similar overexpression of activated (vp-) pou2 resulted in the same effects, whereas repressive (en-) pou2 caused dorsalization, supporting the previously proposed idea that pou2 is involved in DV patterning and that pou2 is a transcriptional activator. In contrast, high-dose mRNA for pou2 and its modified genes affected convergent extension (CE) movement. We observed similar activities for mouse Oct-3/4, suggesting conservation of the roles of this POU family in vertebrate development. To determine the critical stage for the functions of pou2 in embryos, we established a transgenic (Tg) fish line harboring en-pou2 under regulation of a heat-shock promoter (HEP) and found that the exposure of HEP Tg embryos to heat shock at the midblastula (sphere) stage dorsalized embryos, whereas induction of HEP at the late blastula stage (30-50% epiboly) affected CE movement. The defects due to HEP induction were rescued by introducing wild-type pou2 mRNA before the heat treatments. Collectively, these data demonstrated that pou2 regulates DV patterning and CE movement in zebrafish embryos at the midblastula and late blastula stages, respectively.

Having multiple viewpoints are an indispensable capability for persons who can lead the development and operation of large-scale complex technological and social systems. In addition, the previous study describes as follows."Citizens are diverse because our society has become more complex in recent years. Therefore how to evaluate, how to satisfy the required level of accountability, and how to reach a good agreement are problems that must be addressed."This study therefore aims to evaluate whether Goal Structuring Notation (GSN) is a notation method structuralizing with multiple viewpoints for agreement formation. Through the evaluation, this study intends to clarify what it is to structuralize with multiple viewpoints by using GSN. A quantitative evaluation method and a qualitative evaluation method are used for data analysis. This study discusses structuralizing with multiple viewpoints.Concretely, this study showed that structuralizing with multiple viewpoints: 1) Connects multiple viewpoints, creates new boundaries, and enables structuralizing what was described by using GSN, when multiple Strategy nodes are used. 2) Enables expressing a combination of a viewpoint that is selected from multiple viewpoints aligned in the horizontal direction, and a viewpoint that is selected from multiple viewpoints aligned in the vertical direction, when one Strategy node is used. 3) Enables discovering an unexpected viewpoint through a conversation using GSN.Finally, this study concludes with future research topics.

Zebrafish pou2, encoding the class V POU transcription factor orthologous to mouse Oct-3/4, has been implicated in different aspects of development, such as dorsoventral patterning, endoderm formation, and brain regionalization, by analyzing pou2 mutant embryos. In the present study, we first conducted overexpression of pou2-modified genes by mRNA injection, and found that pou2 and its active form (vp-pou2) augmented mesoderm formation and suppressed endoderm specification, whereas repressive pou2 (en-pou2) affected the formation of the mesoderm and endoderm in a different manner. To avoid complications that might arise from different pou2 functions during the course of development, we used a transgenic line harboring inducible en-pou2 (HEP), which could function in a dominant-negative manner. We found that suppressing endogenous pou2 by HEP induction at the mid-blastula stage enhanced endoderm development at the expense of mesoderm, whereas the same treatment in the late blastulae promoted mesoderm formation and suppressed the endoderm specification. Further analyses using HEP induction revealed that, from late epiboly to early somitogenesis, pou2 regulated additional developmental aspects, such as brain regionalization, heart development, and tail formation. Our findings suggest that Pou2 functions in multiple aspects of vertebrate development, especially in the binary decision of the mesendoderm to mesoderm and endoderm in different ways depending on the developmental stage.

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