Aim: The microRNAs (miRNAs) derived from the chromosome 19 miRNA cluster (C19MC) are exclusively expressed in the human placenta, but the origin and functions of C19MC miRNAs are not fully understood. The purpose of this study was to elucidate which cells express C19MC miRNAs in chorionic villi and identify their miRNA targets.Methods: A combination of laser microdissection (LMD) and real‐time polymerase chain reaction (PCR) to examine the localization of five C19MC miRNAs (i.e. miR‐512‐3p, miR‐518b, miR‐520a, miR‐524 and miR‐1323) in the human placenta was performed. Furthermore, to identify miR‐512‐3p‐target genes, we analyzed gene expression profiles of the trophoblast cell line BeWo using a DNA microarray. Predicted target genes were validated by real‐time PCR, western blotting, and 3′‐untranslated region reporter assay.Results: By LMD and subsequent PCR analysis, five C19MC miRNAs examined in this study were predominantly expressed in villous trophoblast cells; little expression, if any, was observed in villous stroma cells or fetal endothelial cells. Microarray data showed that 334 genes were downregulated in BeWo cells treated with Pre‐miR‐512‐3p (mature miR‐512‐3p mimic). We found six candidate target genes of miR‐512‐3p using DNA microarray data and target prediction software. Furthermore, we revealed that protein phosphatase 3, regulatory subunit B, alpha (PPP3R1), one of the six genes, was a miR‐512‐3p target using an in vitro experimental validation system.Conclusion: These data suggest that miR‐512‐3p participates in human trophoblast function[s] by targeting PPP3R1, encoding a regulatory subunit of calcineurin.

The mammalian oviductal lumen is a specialized chamber that provides an environment that strictly regulates fertilization and early embryogenesis, but the regulatory mechanisms to gametes and zygotes are unclear. We evaluated the oviductal regulation of early embryonic development using Ovgp1 (encoding an oviductal humoral factor, OVGP1)-knockout golden hamsters. The experimental results revealed the following: (1) female Ovgp1-knockout hamsters failed to produce litters; (2) in the oviducts of Ovgp1-knockout animals, fertilized eggs were sometimes identified, but their morphology showed abnormal features; (3) the number of implantations in the Ovgp1-knockout females was low; (4) even if implantations occurred, the embryos developed abnormally and eventually died; and (5) Ovgp1-knockout female ovaries transferred to wild-type females resulted in the production of Ovgp1-knockout egg-derived OVGP1-null litters, but the reverse experiment did not. These results suggest that OVGP1-mediated physiological events are crucial for reproductive process in vivo, from fertilization to early embryonic development. This animal model shows that the fate of the zygote is determined not only genetically, but also by the surrounding oviductal microenvironment.

Autonomous personal mobility vehicles (PMVs), such as electric wheelchairs, are meant to drive through pedestrian spaces. Cooperative pedestrian avoidance by PMVs is necessary in these spaces to maintain smooth traffic. Previous studies suggested that PMVs can avoid pedestrians on a shorter path without compromising each other’s acceptability. This avoidance can be realized by understanding how pedestrians react to the behavior of PMVs and considering those characteristics in the autonomous navigation of PMVs. In this study, the characteristics of pedestrian’s avoidance behavior were investigated. Experiments were conducted to understand the influence of the parameters of the PMV’s avoidance behavior on pedestrians. Results showed that the angular velocity of the PMV during avoidance affects the pedestrian’s avoidance width and tolerance against the PMV’s behavior. These results suggest that it is possible to avoid pedestrians in smaller avoidance spaces by controlling the angular velocity of the PMV and maintaining smooth traffic.