G12/13 and Gq mediate S1P2-induced inhibition of Rac and migration in vascular smooth muscle in a manner dependent on Rho but not Rho kinase

金沢大学医薬保健研究域医学系Aims: The lysophospholipid mediator sphingosine-1-phosphate (S1P) activates G protein-coupled receptors (GPCRs) to induce potent inhibition of platelet-derived growth factor (PDGF)-induced Rac activation and, thereby, chemotaxis in rat vascular smooth muscle cells (VSMCs). We explored the heterotrimeric G protein and the downstream mechanism that mediated S1P inhibition of Rac and cell migration in VSMCs. Methods and results: S1P inhibition of PDGF-induced cell migration and Rac activation in VSMCs was abolished by the selective S1P2 receptor antagonist JTE-013. The C-terminal peptides of Gα subunits (Gα-CTs) act as specific inhibitors of respective G protein-GPCR coupling. Adenovirus-mediated expression of Gα12-CT, Gα13-CT, and Gα q-CT, but not that of Gαs-CT or LacZ or pertussis toxin treatment, abrogated S1P inhibition of PDGF-induced Rac activation and migration, indicating that both G12/13 and Gq classes are necessary for the S1P inhibition. The expression of Gαq-CT as well as Gα12-CT and Gα13-CT also abolished S1P-induced Rho stimulation. C3 toxin, but not a Rho kinase inhibitor or a dominant negative form of Rho kinase, abolished S1P inhibition of PDGF-induced Rac activation and cell migration. The angiotensin II receptor AT1, which robustly couples to Gq, did not mediate either Rho activation or inhibition of PDGF-induced Rac activation or migration, suggesting that activation of Gq alone was not sufficient for Rho activation and resultant Rac inhibition. However, the AT1 receptor fused to Gα12 was able to induce not only Rho stimulation but also inhibition of PDGF-induced Rac activation and migration. Phospholipase C inhibition did not affect S1P-induced Rho activation, and protein kinase C activation by a phorbol ester did not mimic S1P action, suggesting that S1P inhibition of migration or Rac was not dependent on the phospholipase C pathway. Conclusion: These observations together suggest that S1P2 mediates inhibition of Rac and migration through the coordinated action of G 12/13 and Gq for Rho activation in VSMCs. © The Author 2008.

Intestinal angina in a patient with hypertrophic obstructive cardiomyopathy: a case report

Background: Intestinal angina is characterized by recurrent postprandial abdominal pain and anorexia. Commonly, these symptoms are caused by severe stenosis of at least two vessels among the celiac and mesenteric arteries. However, intestinal perfusion is affected not only by the degree of arterial stenosis but also by systemic perfusion. We experienced a unique case of intestinal angina caused by relatively mild stenosis of the abdominal arteries complicated with hypertrophic obstructive cardiomyopathy. Case presentation: We report an 86-year old Japanese man with hypertrophic obstructive cardiomyopathy and advanced atrioventricular block who was diagnosed with intestinal angina. Computed tomography showed mild stenosis of the celiac artery and severe stenosis of the inferior mesenteric artery, and these lesions were relatively mild compared with other reports. A dual-chamber pacemaker with right ventricular apical pacing was implanted to improve the obstruction of the left ventricular outflow tract. After implantation, the patient\u27s abdominal symptoms diminished markedly, and improvement of the left ventricular outflow tract obstruction was observed. Conclusions: Although intestinal angina is generally defined by severe stenosis of at least two vessels among the celiac and mesenteric arteries, the present case suggests that hemodynamic changes can greatly affect intestinal perfusion and induce intestinal angina in the presence of mild stenosis of the celiac and mesenteric arteries. © 2016 The Author(s)

Mutant analyses reveal different functions of fgfr1 in medaka and zebrafish despite conserved ligand–receptor relationships

AbstractMedaka (Oryzias latipes) is a small freshwater teleost that provides an excellent developmental genetic model complementary to zebrafish. Our recent mutagenesis screening using medaka identified headfish (hdf) which is characterized by the absence of trunk and tail structures with nearly normal head including the midbrain–hindbrain boundary (MHB). Positional-candidate cloning revealed that the hdf mutation causes a functionally null form of Fgfr1. The fgfr1hdf is thus the first fgf receptor mutant in fish. Although FGF signaling has been implicated in mesoderm induction, mesoderm is induced normally in the fgfr1hdf mutant, but subsequently, mutant embryos fail to maintain the mesoderm, leading to defects in mesoderm derivatives, especially in trunk and tail. Furthermore, we found that morpholino knockdown of medaka fgf8 resulted in a phenotype identical to the fgfr1hdf mutant, suggesting that like its mouse counterpart, Fgf8 is a major ligand for Fgfr1 in medaka early embryogenesis. Intriguingly, Fgf8 and Fgfr1 in zebrafish are also suggested to form a major ligand–receptor pair, but their function is much diverged, as the zebrafish fgfr1 morphant and zebrafish fgf8 mutant acerebellar (ace) only fail to develop the MHB, but develop nearly unaffected trunk and tail. These results provide evidence that teleost fish have evolved divergent functions of Fgf8–Fgfr1 while maintaining the ligand–receptor relationships. Comparative analysis using different fish is thus invaluable for shedding light on evolutionary diversification of gene function

The Japanese space gravitational wave antenna; DECIGO

DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is the future Japanese space gravitational wave antenna. DECIGO is expected to open a new window of observation for gravitational wave astronomy especially between 0.1 Hz and 10 Hz, revealing various mysteries of the universe such as dark energy, formation mechanism of supermassive black holes, and inflation of the universe. The pre-conceptual design of DECIGO consists of three drag-free spacecraft, whose relative displacements are measured by a differential Fabry– Perot Michelson interferometer. We plan to launch two missions, DECIGO pathfinder and pre- DECIGO first and finally DECIGO in 2024

DECIGO pathfinder

DECIGO pathfinder (DPF) is a milestone satellite mission for DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) which is a future space gravitational wave antenna. DECIGO is expected to provide us fruitful insights into the universe, in particular about dark energy, a formation mechanism of supermassive black holes, and the inflation of the universe. Since DECIGO will be an extremely large mission which will formed by three drag-free spacecraft with 1000m separation, it is significant to gain the technical feasibility of DECIGO before its planned launch in 2024. Thus, we are planning to launch two milestone missions: DPF and pre-DECIGO. The conceptual design and current status of the first milestone mission, DPF, are reviewed in this article

シカクマメシュシ セイジュクキ ニ オケルABI3/VP166オ キモトリプシンインヒビターイデンシ ノ ハツゲン ニ オケルBZIPガタ テンシャインシ ノ カンヨ

ABI3/VP1はABA応答配列あるいは保存されたRY配列を介して,植物の種子成熟において多くの遺伝子発現制御を行う重要な転写因子である。シカクマメKunitz型キモトリプシンインヒビター(WCI)遺伝子の時期および器官特異的な遺伝子発現制御の解析から,我々はRY配列がWCI遺伝子の発現制御に必須ではあるが十分ではないことを示した。本研究では,シカクマメからABI3/VP1様のタンパク質(WbABI3)とbZIP型転写因子をクローニングし,これらの因子がWCI遺伝子の発現制御に関与しているか調査した。推定されるアミノ酸配列の解析から,このbZIP型転写因子(WbZIP1)は,インゲンマメにおけるABI3/VP1を介した種子タンパク質遺伝子の転写活性化を抑制する転写因子ROM2と高い相同性を示すことが明らかとなった。大腸菌を用いて発現させた組換えWbZIPタンパク質を用いたゲルシフト解析から,このタンパク質はWCI-3遺伝子プロモーターの5′-ACGT-3′を含むDNA断片に結合することが示された。ノザンブロット解析を行なったところ,WCI-3とWbABI3のmRNAが一過的に蓄積する種子成熟中期の後に,WbZIP1 mRNAの蓄積が増えることが明らかとなった。これらの結果から,WbABI3とWbZIP1はそれぞれ正の制御因子および負の制御因子として,WCI遺伝子の種子成熟中期から後期にかけての一過的な発現を制御していることが考えられた。ABI3/VP1 is an important transcription factor, which regulates the expression of many kinds of genes during plant embryo maturation via ABA responsive elements or conserved RY repeats. The RY repeats are frequently found in 5\u27 upstream regions of seed-specific genes. Through an extensive study of temporally- and spatially-regulated expression of a winged bean chymotrypsin inhibitor (WCI) gene, we have demonstrated that the RY repeat is necessary but not sufficient for the seed-specific expression. In this study, we have cloned cDNAs encoding an ABI3/VP1 like factor (WbABI3) and a bZIP DNA binding protein from winged bean to investigate the participation of ABI3/VP1 and bZIP-type transcription factors in WCI gene expression. The deduced protein sequence of the bZIP protein (WbZIP1) was highly homologous to ROM2, which is shown to be a repressor against ABI3/VP1-activated transcription of MAT class genes during late-seed maturation in French bean. Bacterial recombinant WbZIP1 protein was prepared and tested in a gel mobility shift assay to verify its binding to the promoter region of the WCI-3 gene, which encodes a major WCI protein of winged bean. The recombinant WbZIP1 protein proved to show a high affinity for specific fragments containing 5\u27-ACGT-3\u27 sequences from the WCI-3 promoter. Enhanced expression of the WbZIP1 gene was observed during late-stage seed maturation after the transient expression of WCI-3 and WbABI3 in mid-stage seed maturation. These results suggest that WbABI3 and WbZIP1 may function antagonisitically to tune the level of WCI gene expression from mid- through late-stage seed maturation in winged bean

Replication of Epstein-Barr Virus Primary Infection in Human Tonsil Tissue Explants

Epstein-Barr virus (EBV) may cause a variety of virus-associated diseases, but no antiviral agents have yet been developed against this virus. Animal models are thus indispensable for the pathological analysis of EBV-related infections and the elucidation of therapeutic methods. To establish a model system for the study of EBV infection, we tested the ability of B95–8 virus and recombinant EBV expressing enhanced green fluorescent protein (EGFP) to replicate in human lymphoid tissue. Human tonsil tissues that had been surgically removed during routine tonsillectomy were sectioned into small blocks and placed on top of collagen sponge gels in culture medium at the air-interface, then a cell-free viral suspension was directly applied to the top of each tissue block. Increasing levels of EBV DNA in culture medium were observed after 12–15 days through 24 days post-infection in tissue models infected with B95–8 and EGFP-EBV. Expression levels of eight EBV-associated genes in cells collected from culture medium were increased during culture. EBV-encoded small RNA-positive cells were detected in the interfollicular areas in paraffin-embedded sections. Flow cytometric analyses revealed that most EGFP+ cells were CD3− CD56− CD19+ HLA-DR+, and represented both naïve (immunoglobulin D+) and memory (CD27+) B cells. Moreover, EBV replication in this model was suppressed by acyclovir treatment in a dose-dependent manner. These data suggest that this model has potential for use in the pathological analysis of local tissues at the time of primary infection, as well as for screening novel antiviral agents

Current status of space gravitational wave antenna DECIGO and B-DECIGO

Deci-hertz Interferometer Gravitational Wave Observatory (DECIGO) is the future Japanese space mission with a frequency band of 0.1 Hz to 10 Hz. DECIGO aims at the detection of primordial gravitational waves, which could be produced during the inflationary period right after the birth of the universe. There are many other scientific objectives of DECIGO, including the direct measurement of the acceleration of the expansion of the universe, and reliable and accurate predictions of the timing and locations of neutron star/black hole binary coalescences. DECIGO consists of four clusters of observatories placed in the heliocentric orbit. Each cluster consists of three spacecraft, which form three Fabry-Perot Michelson interferometers with an arm length of 1,000 km. Three clusters of DECIGO will be placed far from each other, and the fourth cluster will be placed in the same position as one of the three clusters to obtain the correlation signals for the detection of the primordial gravitational waves. We plan to launch B-DECIGO, which is a scientific pathfinder of DECIGO, before DECIGO in the 2030s to demonstrate the technologies required for DECIGO, as well as to obtain fruitful scientific results to further expand the multi-messenger astronomy.Comment: 10 pages, 3 figure

The status of DECIGO

DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) is the planned Japanese space gravitational wave antenna, aiming to detect gravitational waves from astrophysically and cosmologically significant sources mainly between 0.1 Hz and 10 Hz and thus to open a new window for gravitational wave astronomy and for the universe. DECIGO will consists of three drag-free spacecraft arranged in an equilateral triangle with 1000 km arm lengths whose relative displacements are measured by a differential Fabry-Perot interferometer, and four units of triangular Fabry-Perot interferometers are arranged on heliocentric orbit around the sun. DECIGO is vary ambitious mission, we plan to launch DECIGO in era of 2030s after precursor satellite mission, B-DECIGO. B-DECIGO is essentially smaller version of DECIGO: B-DECIGO consists of three spacecraft arranged in an triangle with 100 km arm lengths orbiting 2000 km above the surface of the earth. It is hoped that the launch date will be late 2020s for the present