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Most commercial Glycine max (soybean) varieties have yellow seeds because of loss of pigmentation in the seed coat. It has been suggested that inhibition of seed coat pigmentation in yellow G. max may be controlled by homology-dependent silencing of chalcone synthase (CHS) genes. Our analysis of CHS mRNA and short-interfering RNAs provide clear evidence that the inhibition of seed coat pigmentation in yellow G. max results from posttranscriptional rather than transcriptional silencing of the CHS genes. Furthermore, we show that mottling symptoms present on the seed coat of G. max plants infected with some viruses can be caused by suppression of CHS posttranscriptional gene silencing (PTGS) by a viral silencing suppressor protein. These results demonstrate that naturally occurring PTGS plays a key role in expression of a distinctive phenotype in plants and present a simple clear example of the elucidation of the molecular mechanism for viral symptom induction.

As a first step for field applications of stable isotope techniques to investigate the migration of Japanese temperate bass (Lateolabrax japonicus) (Perciformes) juveniles, we conducted a diet switch experiment and fitted an exponential model to changes in stable carbon (δ13C) and nitrogen (δ15N) isotope ratios for muscle, fin, and liver. The trophic enrichment values were ranked liver < muscle < fin for δ13C (range –0.80‰ to +3.66‰) and liver < fin < muscle for δ15N (+0.59‰ to +3.12‰). The half-life values were similar for muscle and fin for both δ13C and δ15N (19.3–25.7 days), while those for liver were 5.3 days for δ13C and 14.4 days for δ15N. Both the δ13C and δ15N values of muscle reached the asymptotic value after a threefold body weight increase, reflecting the diet after the switch. These results suggest that fin is a useful substitute for muscle in field applications of stable isotope techniques and that liver, with a shorter half-life, has the potential to provide more recent information about migration.

Environmental DNA (eDNA) consists of DNA fragments shed from organisms into the environment, and can be used to identify species presence and abundance. This study aimed to reveal the dispersion and degradation processes of eDNA in the sea. Caged fish were set off the end of a pier in Maizuru Bay, the Sea of Japan, and their eDNA was traced at sampling stations located at the cage and 10, 30, 100, 300, 600 and 1000 m distances from the cage along two transect lines. Sea surface water was collected at each station at 0, 2, 4, 8, 24 and 48 h after setting the cage, and again after removing the cage. Quantitative PCR analyses using a species-specific primer and probe set revealed that the target DNA was detectable while the cage was present and for up to 1 h after removing the cage, but not at 2 h or later. Among the 57 amplified samples, 45 (79%) were collected within 30 m from the cage. These results suggest that eDNA can provide a snapshot of organisms present in a coastal marine environment.

SummaryVirus-induced gene silencing (VIGS) is a powerful tool for functional analysis of genes in plants. A wide-host-range VIGS vector, which was developed based on the Cucumber mosaic virus (CMV), was tested for its ability to silence endogenous genes involved in flavonoid biosynthesis in soybean. Symptomless infection was established using a pseudorecombinant virus, which enabled detection of specific changes in metabolite content by VIGS. It has been demonstrated that the yellow seed coat phenotype of various

Objective-Apelin is an endogenous ligand for the G protein-coupled receptor, APJ, and participates in multiple physiological processes. To identify the roles of endogenous apelin, we investigated the phenotype of apelin-deficient (apelin-KO) mice. Methods and Results-Apelin-KO mice showed impaired retinal vascularization and ocular development, which were analyzed by histology, immunohistochemistry, real-time polymerase chain reaction, and the mouse corneal micropocket assay. Apelin-KO mice showed significantly impaired retinal vascularization in the early postnatal period. Retinal apelin/APJ mRNAs were transiently upregulated during the first 2 postnatal weeks but were undetectable in adults. There were no differences in VEGF or FGF2 mRNA expression, or in the morphology and localization of GFAP-positive astrocytes, in the apelin-KO retinas at P5. The corneal pocket assay showed that angiogenic responses to VEGF and FGF2 were remarkably decreased in apelin-KO mice. The reduced responses to VEGF and FGF2 in apelin-KO mice were partially restored by apelin, but apelin alone did not induce angiogenesis. Conclusions-Our See accompanying article on page 1687Apelin/APJ mRNAs are expressed in multiple tissues, primarily in vascular endothelial cells, where they may contribute to angiogenesis. 8,9 Apelin stimulates the proliferation and migration of RF/6A cells, an endothelial cell line of monkey retina, thereby demonstrating angiogenic-like effects. 9 Similarly, apelin is a potent angiogenic factor required for the normal vascular development of frog embryos. 8 During mouse and frog embryonic development, the APJ receptor is highly expressed in endothelial precursor cells and in nascent vascular structures. Apelin is a potent angiogenic factor in 2 in vivo angiogenesis assays, the frog embryo and the chicken chorioallantoic membrane (CAM) assay. 8 More recently, Kidoya et al showed that the apelin/APJ system is involved in the regulation of blood vessel diameter during angiogenesis. 10 In the mouse, the formation of retinal vessels begins at birth and follows a centrifugal extension of retinal vessels from the optic disc to the periphery of the retina. Interestingly, retinal expression of APJ mRNA is observed during the formation of retinal vessels and traces the centrifugal extension of the superficial vasculature bed, whereas that of apelin mRNA is localized in "tip cells," an endothelial subpopulation that forms cell protrusions and directs the polarized extension of the vascular network. 11 In a mouse model of hypoxia-induced retinopathy of prematurity, APJ mRNA transcripts are localized in endothelial cells, and their expression traces the centripetal extension of the retinal network from the periphery of the retina to the optic disc. 12 These findings suggest that apelin/APJ signaling is involved in regulating retinal vascularization.Ocular developmental vascularization is a complex process, which requires the strict coordination of numerous molecular and cellular interactions. Retinal vascularization is contro...

Subcellular resolution imaging of the whole brain and subsequent image analysis are prerequisites for understanding anatomical and functional brain networks. Here, we have developed a very high-speed serial-sectioning imaging system named FAST (block-face serial microscopy tomography), which acquires high-resolution images of a whole mouse brain in a speed range comparable to that of light-sheet fluorescence microscopy. FAST enables complete visualization of the brain at a resolution sufficient to resolve all cells and their subcellular structures. FAST renders unbiased quantitative group comparisons of normal and disease model brain cells for the whole brain at a high spatial resolution. Furthermore, FAST is highly scalable to non-human primate brains and human postmortem brain tissues, and can visualize neuronal projections in a whole adult marmoset brain. Thus, FAST provides new opportunities for global approaches that will allow for a better understanding of brain systems in multiple animal models and in human diseases.

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