No abstract

Analysis of 41 histone homologous clones from an isogenic gene library of Drosophila melanogaster showed that non-histone fragments interrupt the histone repetitive clusters at several sites. Long (L) and short (S) forms of the repeating units are distinguished by the insertion of 240 bp into the spacer between H1 and H3 of the L units; Each form appears to be clustered with its own kind. The complete DNA sequence of the histone 5.0 kb repeating unit was determined. Five histone genes (H1, H2A, H2B, H3, H4) were identified in a repeating unit and several sequence blocks common to the five histone genes were found in the 5'- and 3'-regions. The insertion sequence of 240 bp was found to be similar to the Alu family, an element derived from tRNA.

Dipterocarpoideae, the largest sub-family of well-known plant family Dipterocarpaceae, dominates in South Asian rain forests. Although several previous studies addressed the phylogeny of the Dipterocarpaceae family, relationships among many of its genera from the Dipterocarpoideae sub-family are still not well understood. In particular, little is known about the relationships of the genera Vateriopsis , Stemonoporus , Vateria and inconsistence remains between phylogenetic results and taxonomic classifications of Shorea and Hopea species. We studied molecular phylogeny of the sub-family Dipterocarpoideae using the trnL-trnF spacer, trnL intron and the matK gene sequences of chloroplast DNA (cpDNA). This study is the first comprehensive phylogeny reconstruction for the sub-family Dipterocarpoideae based on cpDNA, as it includes most genera (14) and a large number of species (79) with most species endemic to Sri Lanka, as well as one species from Seychelles and one species from the genus Monotes from Madagascar. Phylogenetic trees were constructed using the Neighbor Joining (NJ) and Maximum Likelihood (ML) methods using combined set of sequences including all three cpDNA regions. The topologies of the NJ and ML trees were to a certain extent, consistent with the current taxonomy of Dipterocarpoideae based on morphology and with previous molecular phylogenies based on cpDNA. Furthermore, our results provided new evidence regarding the relationships of the following genera: Vateriopsis and Stemonoporus and about the validity of the previous morphology based classifications of Shorea species. In addition, the topology of our trees was consistent with the classification of Shorea species proposed by Maury (1978), Maury-Lechon (1979) and Symington (1943). Finally, our results provided evidence for the affinity of the genus Monotes to Asian Dipterocarpoideae rather than to Tiliaceae and indicated that it is a good candidate for outgroup species for future studies of the former sub-family.

No abstract

Silica-supported vanadium oxide (V2O5/SiO2) and alkali-ion (Na+, K+, or Rb+)-modified V2O5/SiO2 samples have been characterized by diffuse reflectance UV−vis spectroscopy, Raman spectroscopy, X-ray absorption spectroscopy (XANES and EXAFS), and XPS. The structure of vanadium species in V2O5/SiO2 has been confirmed to be of a (VO)O3 tetrahedron. The addition of alkali ions to V2O5/SiO2 has caused neither the change of the coordination number of vanadium ions nor the formation of alkali vanadates on the silica support. In alkali-ion-modified V2O5/SiO2 samples, the structure of vanadium species has also been a VO4 tetrahedron, and the bond lengths of V−O have been longer than those of V2O5/SiO2. A rubidium ion has located at ca. 3.3 Å from a vanadium atom and interacted with two V−O bonds directly. Ab initio molecular orbital calculations have indicated that the proposed structures of vanadium species in V2O5/SiO2 and alkali-ion-modified V2O5/SiO2 samples are reasonable. In addition, it has been clarified that by adsorption of water molecules, the structure of vanadium species in alkali-ion-modified V2O5/SiO2 samples is kept tetrahedral, while that in V2O5/SiO2 changes to a distorted octahedral one.

Invasion and metastasis of cancer cells are the major causes of high motality in cancer patients. Matrix metalloproteinases (MMPs) are zinc-dependent proteolytic enzymes capable of degrading the components of extracellular matrix (ECM), including type IV collagen, gelatin and fibronectin. Cancer cells destruct surrounding tissues by enzymatic action of MMPs, leading to cancer invasion and metastasis. Among several MMPs, MMP-2, -7 and -9 are considered to be involved in cancer invasion and metastasis. In particular, MMP-7 is frequently found to overexpress in the invasive edge of cancer cells and play important roles in invasion or metastasis of digestive cancer. 1,2) Recently, the attempt to search for MMP inhibitors from plants is being performed, and several investigators have reported the inhibitory effects of epigallocatechin, 3) caffeic acid, 4) and proanthocyanin 5) on gene expression or enzymatic activity of MMP-2 and -9. However, except for the papers by Kawabata et al.,[6][7][8] little attention has been given to the development of MMP-7 inhibitors.Isofraxidin occurs in a variety of plants including Acansopanax senticosus HARMs (Japanese name: Ezoukogi). As the major compounds of Acanthopanax senticosus, eleutheroside B, B1, E, isofraxidin, and chlorogenic acid have been identified, isolated, and reported to possess several biological activities, such as anti-stress, anti-fatigue, antigastric ulcer, anti-depressive, immuno-enhancing and antiinflammatory effects. [9][10][11][12][13][14][15][16] We previously examined the effect of isofraxidin on the expression of inflammatory mediator cyclooxygenase-2 (COX-2) mRNA and found inhibitory effects at a significant level on human synovial sarcoma cell line SW982 cells. [11][12][13][14][15][16] In this study, we investigated isofraxidin in its anti-tumor effects on human hepatoma cell lines in cellular and molecular terms. MATERIALS AND METHODSCell Culture Human hepatoma cell lines HuH-7, HepG2 and HLE and a human lung fibroblast cell line IMR90 were obtained from Japanese Collection of Research Bioresources (JCRB). Cells were grown in RPMI-1640 culture medium supplemented with 10% fetal bovine serum (FBS), 100 U/ml penicillin, and 100 mg/ml streptomycin at 37°C in a humidified atmosphere of 5% CO 2 and 95% air.Phenolic Compounds Isofraxidin was purchased from Wako Pure Chemical Industries, Ltd. (Osaka, Japan). Eleutheroside E was purchased from Phytochem Referenzsubstanzen GbRmb (Ichenhausen, Germany). The compounds were added to the culture medium at appropriate concentrations as a dimethylsulfoxide (DMSO) solution (the final DMSO concentration was 0.5% in all cultures), and the same amount of vehicle was added to the control cultures.3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium Bromide (MTT) Assay For cell attachment study, cells were plated in 96-well plates at 3.0ϫ10 4 cells/cm 2 (low cell density) in 0.1 ml of serum-free RPMI-1640 medium containing or not containing isofraxidin and incubated for 24 h. For cell growth study, cells were plated i...

A total of 53 dipterocarp species belonging to ten genera were studied to examine phylogenetic relationships using the sequences of iwo non-coding regions in chloroplast DNA. Richetioides. The genera Shorea and Hopea werc more divergenl than the other genera. These resulls suggest that they are the groups of phylogenetically more diversified species.

To evaluate the genetic diversity of a mangrove species and clarify the genetic structure of its populations, we studied nucleotide polymorphism in two DNA regions of Bruguiera gymnorhiza collected from the southern islands of Japan, Thailand, Malaysia, Indonesia, Micronesia, and India. The two DNA sequences were the chloroplast (cp) intergenic spacer between trnL and trnF genes (ca. 300 bp), and a part (ca. 550 bp) of the nuclear gene coding for glyceraldehyde-3-phosphate dehydrogenase (GapCp). Little polymorphism was found within each of the three geographical regions, Pacific Ocean, Bay of Bengal and Arabian Sea. Throughout the vast regions east of the Malay peninsula including Indonesia, Thailand, Micronesia and the southern islands of Japan (Pacific Ocean), essentially only one haplotype (apart from variation in number of a T repeat) was present. A second haplotype was present on the western coast of Malay Peninsula and the eastern coast of India (Bay of Bengal). On the southwest of Malay Peninsula both of these haplotypes were present. Finally a third haplotype was found only on the western coast of India (Arabian Sea). When taken over all geographic populations, total nucleotide variation within the species was large (l = 0.006, average of the two genes). Our results are consistent with the hypothesis that this low genetic diversity within any local population and differentiation between the different oceans or regions are caused by very low gene flow between each of the different oceans coupled with frequent fluctuation of population sizes due to the change in sea level. The significance of these results is discussed from evolutionary point of the mangrove forests.