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The station coordinates derived from GNSS (Global Navigation Satellite System) with a conventional static method underpin the study of Earth and planetary science and surveying and mapping. For the continuous provision of high-quality coordinates, it is mandatory to cope with the increasing deviation from the global standard reference frame and the launch of modern GPS (Global Positioning System) satellites. To provide coordinates agreed with ITRF2014 (International Terrestrial Reference Frame 2014) at several millimeters for GEONET (GNSS Earth Observation Network System) in Japan, we developed a new analysis strategy named F5 and assessed the reprocessed station coordinates from 1996. The major updates in F5 can be summarized as incorporating global network processing and enhancements in troposphere modeling. As for the troposphere enhancements, a modern mapping function VMF1 (Vienna Mapping Functions 1) was employed and time intervals for troposphere estimates were shortened. Station coordinates in the global network showed a great agreement with ITRF2014 at several millimeters in the recent 20 years and comparable or slightly better performance with IGS (International GNSS Services) Analysis Centers. The RMS (root mean square) averaged over all GEONET stations indicated very high accuracy of 3.2 mm (horizontal) and 7.3 mm (vertical); the latter accounts for an improvement of roughly 10% from the previous strategy. Sensitivity tests about troposphere estimates revealed that the reduced RMS was completely due to the short time intervals, not the use of VMF1, which contributed to partly suppressing the spurious vertical annual deformation. These results confirm that F5 is sufficiently accurate for the requirements of individual applications and infer the capability of detecting smaller signals the previous strategy could not resolve. [ABSTRACT FROM AUTHOR]

Paternal genome reprogramming, such as protamine–histone exchange and global DNA demethylation, is crucial for the development of fertilised embryos. Previously, our study showed that one of histone arginine methylation, asymmetrically dimethylated histone H3R17 (H3R17me2a), is necessary for epigenetic reprogramming in the mouse paternal genome. However, roles of histone arginine methylation in reprogramming after fertilisation are still poorly understood. Here, we report that H3R2me2s promotes global transcription at the 1-cell stage, referred to as minor zygotic genome activation (ZGA). The inhibition of H3R2me2s by expressing a histone H3.3 mutant H3.3R2A prevented embryonic development from the 2-cell to 4-cell stages and significantly reduced global RNA synthesis and RNA polymerase II (Pol II) activity. Consistent with this result, the expression levels of MuERV-L as minor ZGA transcripts were decreased by forced expression of H3.3R2A. Furthermore, treatment with an inhibitor and co-injection of siRNA to PRMT5 and PRMT7 also resulted in the attenuation of transcriptional activities with reduction of H3R2me2s in the pronuclei of zygotes. Interestingly, impairment of H3K4 methylation by expression of H3.3K4M resulted in a decrease of H3R2me2s in male pronuclei. Our findings suggest that H3R2me2s together with H3K4 methylation is involved in global transcription during minor ZGA in mice. [ABSTRACT FROM AUTHOR]

Context: Habitat fragmentation is likely to have deleterious genetic consequences for plant populations. Although the genetic effects of fragmentation in plants have been investigated in various landscapes, such studies are scarce in urban landscapes where forests tend to be fragmented and have a complex internal structure. Objectives: This study aimed to determine the factors, including patch and sub-patch level spatial factors, affecting the genetic diversity of a herbaceous species in urban fragmented forests. Methods: We collected 30-39 leaf samples of Viola grypoceras A. Gray var. grypoceras, a perennial herbaceous species with short-distance seed dispersal, from 12 fragmented and 12 suburban forests each at Kyoto City, Japan, and analyzed the genetic diversity of this species by developing six simple sequence repeat markers. Field survey was conducted to collect demographic and spatial data. Results: There was no significant difference in allelic richness between the urban fragmented and suburban forests. However, statistical analysis revealed that the area of vegetation, distribution pattern of populations in a forest, and average distance between nearest populations affected the genetic diversity of this species in urban fragmented forests. Conclusion: Although V. grypoceras has traits that allow it to tolerate fragmentation, such as self-pollination and seed bank-formation ability, pure loss of habitat and reduced fragment size might have deleterious effects on this species, and these effects might become more apparent if fragmentation continues to proceed in the future. [ABSTRACT FROM AUTHOR]

We report a functional neuroimaging study of a 43-year-old woman with Nasu-Hakola disease (NHD). Regional cerebral blood flow (rCBF) images were measured with technetium-99m ethyl cysteinate dimer single photon emission computed tomography (SPECT). rCBF was decreased in the bilateral frontal lobes and thalamus. This finding was consistent with the known underlying neuropathology in patients with NHD. Brain SPECT is useful for demonstrating the pathophysiologic brain region in patients with NHD. [ABSTRACT FROM AUTHOR]

Wild-derived mice have contributed to experimental mouse genetics by virtue of their genetic diversity, which may help increase the chance of identifying novel modifier genes responsible for specific phenotypes and diseases. However, gene targeting using wild-derived mice has been unsuccessful because of the unavailability of stable embryonic stem cells. Here, we report that CRISPR/Cas9-mediated gene targeting can be applied to the Japanese wild-derived MSM/Ms strain (Mus musculus molossinus). We targeted the nonagouti (a) gene encoding the agouti protein that is localized in hair and the brain. We obtained three homozygous knockout mice as founders, all showing black coat colour. While homozygous knockout offspring were physiologically indistinguishable from wild-type litter-mates, they showed specific domesticated behaviours: hypoactivity in the dark phase and a decline in the avoidance of a human hand. These phenotypes were consistent over subsequent generations. Our findings support the empirical hypothesis that nonagouti is a domestication-linked gene, the loss of which might repress aggressive behaviour. [ABSTRACT FROM AUTHOR]