Techniques of SNP genotyping and remote sensing applied for elucidation of the contribution of polygene and environmental factors to inter-individual variation in skin pigmentation phenotype

We present a conceptual framework for applying techniques of SNP genotyping as a molecular biological approach and remote sensing as an ecological approach to elucidation of the contribution of polygene and environmental factors to inter-individual variation in skin pigmentation phenotype. Additionally, we discuss the obstacles that frustrate our efforts to identify how the human genome encodes the complex phenotype and suggest the use of computational methods designed for knowledge discovery within hereditary database.     

Collective oscillations in developing cells: insights from simple systems

From hormonal secretion to gene expression, multicellular dynamics are rich in oscillatory regulation. When organized in space and time, periodic cell-cell signaling can give rise to long-range coordination of gene expression and cell movement in tissues. Lack of synchrony of the oscillations on the other hand can serve as a source of initial divergence of cell fate in stem cells. How properties of individual cells can account for collective rhythmic behaviors at the tissue level remains elusive in most cases. Recently, studies in chemical reactions, synthetic gene circuits, yeast and social amoeba Dictyostelium have greatly enhanced our view of collective oscillations in cell populations. From these relatively simple systems, a unified view of how excitable and oscillatory regulations could be tuned and coupled to give rise to tissue-level oscillations is emerging. The review focuses on recent progress in cyclic adenosine monophosphate oscillations in Dictyostelium and highlights similarities and differences with other systems. We will see that the autonomy of single-cell level oscillations and different ways in which cells are coupled influence how group-level information can be encoded in collective oscillations.     

The AtXTH28 Gene, a Xyloglucan Endotransglucosylase/Hydrolase, is Involved in Automatic Self-Pollination in Arabidopsis thaliana

Successful automatic self-pollination in flowering plants isdependent on the correct development of reproductive organs.In the stamen, the appropriate growth of the filament, whichlargely depends on the mechanical properties of the cell wall,is required to position the anther correctly close to the stigmaat the pollination stage. Xyloglucan endotransglucosylase/hydrolases(XTHs) are a family of enzymes that mediate the constructionand restructuring of xyloglucan cross-links, thereby controllingthe extensibility or mechanical properties of the cell wallin a wide variety of plant tissues. Our reverse genetic analysishas revealed that a loss-of-function mutation of an ArabidopsisXTH family gene, AtXTH28, led to a decrease in capability forself-pollination, probably due to inhibition of stamen filamentgrowth. Our results also suggest that the role of AtXTH28 inthe development of the stamen is not functionally redundantwith its closest paralog, AtXTH27. Thus, our finding indicatesthat AtXTH28 is specifically involved in the growth of stamenfilaments, and is required for successful automatic self-pollinationin certain flowers in Arabidopsis thaliana.     

Vegetation succession at the abandoned Ogushi sulfur mine, central Japan

We surveyed plant community development at the abandoned Ogushi sulfur mine. We found seven communities dominated by the following respective species: Deschampsia flexuosa, Miscanthus sinensis, shrub willow, Gaultheria miqueliana–Betula ermanii, Sasa senanensis–Betula ermanii, willow–Betula ermanii, and Sasa kurilensis–Abies veitchii. We examined the succession of these communities, in which younger communities of low height and ground cover contained seedlings of the successive communities that were taller and had higher ground cover. To understand the development of these different communities, we surveyed damage from mining pollution and effects of immature soils formed by landslides. The average pH (H₂O) was 4.12, and aluminum concentrations were not sufficiently high to damage plant growth, except in areas where sulfur had been mined. The organic carbon and nitrogen content in soil samples were very low because of a delay in soil development caused by a large landslide in 1937. Hence, succession was positively correlated with the soil development stage. The delay in soil development after a large landslide influenced the seven successional steps of the plant communities, but mineral poisons at the abandoned Ogushi sulfur mine had no effect on succession.     

Effects of rosuvastatin on electronegative LDL as characterized by capillary isotachophoresis: the ROSARY Study

Electronegative LDL, a charge-modified LDL (cm-LDL) subfraction that is more negatively charged than normal LDL, has been shown to be inflammatory. We previously showed that pravastatin and simvastatin reduced the electronegative LDL subfraction, fast-migrating LDL (fLDL), as analyzed by capillary isotachophoresis (cITP). The present study examined the effects of rosuvastatin on the more electronegative LDL subfraction, very-fast-migrating LDL (vfLDL), and small, dense charge-modified LDL (sd-cm-LDL) subfractions. Patients with hypercholesterolemia or those who were being treated with statins (n = 81) were treated with or switched to 2.5 mg/d rosuvastatin for 3 months. Rosuvastatin treatment effectively reduced cITP cm-LDL subfractions of LDL (vfLDL and fLDL) or sdLDL (sd-vfLDL and sd-fLDL), which were closely related to each other but were different from the normal subfraction of LDL [slow-migrating LDL (sLDL)] or sdLDL (sd-sLDL) in their relation to the levels of remnant-like particle cholesterol (RLP-C), apolipoprotein (apo) C-II, and apoE. The percent changes in cm-LDL or sd-cm-LDL caused by rosuvastatin were correlated with those in the particle concentrations of LDL or sdLDL measured as LDL-apoB or sdLDL-apoB and the levels of HDL-C, RLP-C, apoC-II, and apoE. In conclusion, rosuvastatin effectively reduced both the vfLDL subfraction and sd-cm-LDL subfractions as analyzed by cITP.     

Generation of retinal pigment epithelial cells from human embryonic stem cell-derived spherical neural masses

Dysfunction and loss of retinal pigment epithelium (RPE) are major pathologic changes observed in various retinal degenerative diseases such as aged-related macular degeneration. RPE generated from human pluripotent stem cells can be a good candidate for RPE replacement therapy. Here, we show the differentiation of human embryonic stem cells (hESCs) toward RPE with the generation of spherical neural masses (SNMs), which are pure masses of hESCs-derived neural precursors. During the early passaging of SNMs, cystic structures arising from opened neural tube-like structures showed pigmented epithelial morphology. These pigmented cells were differentiated into functional RPE by neuroectodermal induction and mechanical purification. Most of the differentiated cells showed typical RPE morphologies, such as a polygonal-shaped epithelial monolayer, and transmission electron microscopy revealed apical microvilli, pigment granules, and tight junctions. These cells also expressed molecular markers of RPE, including Mitf, ZO-1, RPE65, CRALBP, and bestrophin. The generated RPE also showed phagocytosis of isolated bovine photoreceptor outer segment and secreting pigment epithelium-derived factor and vascular endothelial growth factor. Functional RPE could be generated from SNM in our method. Because SNMs have several advantages, including the capability of expansion for long periods without loss of differentiation capability, easy storage and thawing, and no need for feeder cells, our method for RPE differentiation may be used as an efficient strategy for generating functional RPE cells for retinal regeneration therapy.     

Serum miR-1297: a promising diagnostic biomarker in esophageal squamous cell carcinoma

We aimed to value the diagnostic potential of serum miR-1297 in esophageal squamous cell cancer (ESCC). Its expression level was detected in 156 pairs of patients with ESCC and healthy volunteers using quantitative real-time polymerase chain reaction (qRT-PCR) method. It was statistically decreased in ESCC patients compared with healthy controls. AUC based on serum miR-1297 was 0.840?±?0.035 in discovery group and 0.837?±?0.034 in validation group. Further analysis on early-stage patients revealed that the AUC was 0.819?±?0.053 in discovery group and 0.814?±?0.044 in validation group. Its sensitivity and specificity were promising. In conclusion, serum miR-1297 can serve as an ideal indicator for the diagnosis of ESCC.     

Long-term adaptation of the Bombyx mori BmN4 cell line to grow in serum-free culture

Bombyx mori ovary-derived BmN4 cells have been successfully adapted to a commercial serum-free medium (SFM; SF900-II) by gradually reducing the serum-containing TC-100 medium content from 100 to 0% (v/v). The BmN4 cells adapted to the SFM (BmN-SFM) adhered strongly to the culture flask and showed altered cell morphology. The BmN-SFM was subcultured 200 times, and the population doubling time was 4.70 d. Infection studies showed that BmN-SFM cells were easily susceptible to B. mori nucleopolyhedrovirus (BmNPV), and both the multiplication of budded virus and the promoter activity of the polyhedrin gene in BmN-SFM cells were almost the same as those in BmN4 cells before adaptation. Additionally, mouse interleukin-3 expressed by a recombinant BmNPV was normally secreted and modified with N-linked glycans in BmN-SFM cells. These findings indicate that BmN-SFM is particularly useful for a BmNPV-based baculovirus expression vector system with serum-free conditions.