Distribution and change patterns of free IAA, ABP 1 and PM H⁺-ATPase during ovary and ovule development of Nicotiana tabacum L

Auxin plays key roles in flower induction, embryogenesis, seed formation and seedling development, but little is known about whether auxin regulates the development of ovaries and ovules before pollination. In the present report, we measured the content of free indole-3-acetic (IAA) in ovaries of Nicotiana tabacum L., and localized free IAA, auxin binding protein 1 (ABP1) and plasma membrane (PM) H⁺-ATPase in the ovaries and ovules. The level of free IAA in the developmental ovaries increased gradually from the stages of ovular primordium to the functional megaspore, but slightly decreased when the embryo sacs formed. Immunoenzyme labeling clearly showed that both IAA and ABP1 were distributed in the ovules, the edge of the placenta, vascular tissues and the ovary wall, while PM H⁺-ATPase was mainly localized in the ovules. By using immunogold labeling, the subcellular distributions of IAA, ABP1 and PM H⁺-ATPase in the ovules were also shown. The results suggest that IAA, ABP1 and PM H⁺-ATPase may play roles in the ovary and ovule initiation, formation and differentiation.     

Energetic metabolism,stress, and immunity—development of population physiology

This review shows that the interpenetration of population ecology and animal physiology positively affects the both scientific directions that are important fields of modern zoology. Due to progress in the development of telemetry and non-invasive methods to assess the animal state, as well as of moleculargenetic methods that permit to distinguish the markers reflecting the individual history of an individual, the possibilities of studying responses of an organism to environmental impacts have been greatly expanded. The combined use of traditional ecological and modern physiological, immunological, and molecular-genetic methods promotes to reveal mechanisms responsible for the stable existence of population in the dynamic environment. In addition, the analysis of the contribution of physiological and immunological processes to the formation of adaptations on the population level is a requirement to understand their adaptive importance, which is not always evident when considering a problem at the organism-centric level.     

An inventory of the mires of Hokkaido,Japan—their development,classification, decline,and conservation

Hokkaido Island is located in the cool temperate zone, and its climate conditions facilitated the formation of a variety of wetland types, the majority of them peat-forming mires. Most of these remained in a natural state until the early 20th century. However, drainage and subsequent conversion mostly to agricultural land have since destroyed more than 70% of the original wetland ecosystems. This paper (1) provides an overview of mire types, (2) reviews the development process of mires in Hokkaido during the Holocene, (3) analyzes the causes of losses of wetland areas, and (4) gives a summary of the current conservation and management status. Basic mire types that have been described in other parts of the northern hemisphere can also be recognized in Hokkaido, although there are floristic differences, and the frequency and intensity of volcanic impact and tsunamis is higher than in most other regions with abundant mire formation. Mire formation started at various points during the postglacial period; a few mountain mires in southwest Hokkaido date back to the Lateglacial, but most mountain mires formed during the mid to late Holocene. Most lowland mires developed at altitudes below 20 m and were influenced by the Jomon transgression that peaked ca. 6,000 years BP. The largest lowland mires started forming after the sea retreated, and many are not older than ca. 3,000 years. In 1996, the total number of wetlands (including peat-forming mires, freshwater marshes, and saltmarshes) greater than 1 ha was 150, with a total area of 59,881 ha. In 1928, when many wetlands were yet undeveloped, their total area was 200,642 ha. Most losses occurred between the 1950s and 1970s, when post-war development economics promoted agriculture and large-scale reclamation projects. Currently, 90.7% of mountain wetlands are public land, while 81.3% of the lowland wetlands are private or in mixed ownership. The ownership condition affects the possibilities for the protection of complete mire complexes especially in the lowlands. For effective conservation of wetland ecosystems it is necessary to include the catchment area in the planning of protected areas.     

Molecular and Histochemical Analysis of a T-DNA Tagged Mutant of Arabidopsis Exhibiting Anther — Specific GUS Expression

An Arabidopsis thaliana mutant, exhibiting anther specific GUS expression, identified from a mutant population of Arabidopsis tagged with a promoterless β-glucuronidase (GUS), carries the T-DNA insertions at two distinct loci. We have been able to segregate the two inserts from each other by backcrossing with wild type plants. The insertion responsible for anther specific GUS expression in segregating population has been identified and confirmed to be in the upstream region of a putative peroxidase gene, AT2G24800. Here we report detailed histochemical and molecular characterization of the mutant Anth85, carrying a single insertion of T-DNA in the peroxidase gene. In Anth85, the GUS expression was observed in the anthers and rosette of the young seedlings. The expression of GUS in the anthers was restricted to the tapetum and microspores. The mutant has no developmental defects and the gene appears to be redundant for normal plant growth. Cloning of upstream region and detailed deletion study of upstream region in transgenic plants is likely to lead to the identification of anther specific promoter elements.     

Anther cultures of tetraploid Solanum genotypes—the influence of gelling agents and correlations between incubation temperature and pollen germination temperature

Four tetraploid potato genotypes (194.10, 199.13, 201.5, 201.12) were examined in anther culture. The androgenic responses were in general high. Cv. 199.13 contributed with the best response, varying between 0.38 and 0.55 embryoids per anther. Gellan gum or potato starch were used as gelling agents in a double-layer medium. Anthers incubated on potato starch gave a higher embryo yield in the beginning of the culture period, compared to anthers cultivated on gellan gum. The number of embryoids per anther, however, was higher on gellan gum at the end of the culture period. Anther cultures of potato were incubated in two different temperatures (20 °C and 25 °C), and the highest embryo yield was obtained in 25 °C except for genotype 201.12 where no difference was found between the two temperatures. Experiments with pollen germination in various temperatures (10 °C and 20 °C) were correlated to anther culture experiments. Also in case of pollen germination, genotype 201.12 was temperature-independent, while germination was stimulated by higher temperatures in the other genotypes.     

Aptamers—basic research, drug development, and clinical applications

Since its discovery in the early 1990s, aptamer technology has progressed tremendously. Automated selection procedures now allow rapid identification of DNA and RNA sequences that can target a broad range of extra- and intracellular proteins with nanomolar affinities and high specificities. The unique binding properties of nucleic acids, which are amenable to various modifications, make aptamers perfectly suitable for different areas of biotechnology. Moreover, the approval of an aptamer for vascular endothelial growth factor by the US Food and Drug Administration highlights the potential of aptamers for therapeutic applications. This review summarizes recent developments and demonstrates that aptamers are valuable tools for diagnostics, purification processes, target validation, drug discovery, and even therapeutic approaches.     

Interleukin-1β and mitochondria damage, and the development of diabetic retinopathy

Mitochondrial dysfunction is considered to play an important role in the development of diabetic retinopathy. Recent evidence has also shown many similarities between diabetic retinopathy and a low grade chronic inflammatory disease. The aim of this study is to understand the interrelationship between proinflammtory mediator, IL-1β and mitochondrial dysfunction in the accelerated loss of capillary cells in the retina. Using IL-1β receptor gene knockout (IL-1R1^?/^?) diabetic mice, we have investigated the effect of regulation of IL-1β on mitochondrial dysfunction and mtDNA damage, and increased retinal capillary cell apoptosis and the development of retinopathy. Retinal mitochondrial dysfunction and mtDNA damage were significantly ameliorated in IL-1R1^?/^? mice, diabetic for ~10 months, compared to the wild-type diabetic mice. This was accompanied by protection of accelerated capillary cell apoptosis and the development of acellular capillaries, histopathology associated with diabetic retinopathy. Thus, mitochondrial damage could be one of the key events via which increased inflammation contributes to the activation of the apoptotic machinery resulting in the development of diabetic retinopathy, and the possible mechanism via which inflammation contributes to the development of diabetic retinopathy includes continuous fueling of the vicious cycle of mitochondrial damage, which could be disrupted by inhibitors of inflammatory mediators.     

Cell wall functions in growth and development —a physical and chemical point of view

The plant cell changes its cell wall architecture during growth and development through synthesis and degradation of wall polysaccharides. Changes of chemical components in the cell wall include not only the synthesis and degradation but also the shift of molecular-weight distribution of certain species of the component polysaccharides. The changes in chemical structure, in turn lead to alteration of physical properties of the cell wall. Changes of physical parameters of cell walls obtained by a physical method accord with the biochemical degradation of polysaccharides. The changes in chemical structures of the cell wall are regulated by plant hormones, stress signals and gene expression. The physical and chemical studies of the cell wall have disclosed that degradation and/or depolymerization of wall polysaccahrides causes decrease in viscosity of the cell wall, leading further extension of the cell wall even under the unchanged osmotic relation. Furthermore, cell walls of outer and inner tissues play different regulatory roles in tissue growth and stem strength was governed by the number of cellulose molecules in the cell wall. Recipient of the Botanical Society Award for Young Scientists, 1990.     

Ontogeny and localization of the α, β, and γ crystallins in newt eye lens development

The α-, β-, and γ-crystallins, proteins characteristic for the vertebrate eye lens, have been localized in the developing lens of Notophthalmus viridescens, the eastern spotted newt. Using the immunofluorescence technique, antibodies to the α-, β-, and γ-crystallin classes were applied to tissue sections through the eye region of developing N. viridescens embryos, Harrison (external) Stages 30 to 46+. β-Crystallins were the first of the crystallins to appear in a few cells of the lens vesicle even before the lengthening of the prospective primary fiber cells. γ-Crystallins were first detectable at a slightly more advanced stage in the prospective primary fibers, and α-crystallins in a few cells of the beginning primary fiber area. The external layer/epithelium was negative for β-crystallins until late in lens morphogenesis, and α- and γ-crystallins could not be detected in these cells at any time. This, the first use in amphibia of homologous antibodies specific for the crystallin classes, makes clear that phylogenetic differences exist as to the primacy and relevance of specific crystallins to events during morphogenesis of the eye lens.     

Introduction—development and phylogeny of the arthropods: Darwin’s legacy

In the present essay, I first recall the genealogical concept of classification settled by Charles Darwin in the Origin of Species. Darwin tightly linked what we now call phylogeny and development. He often insisted to take into account embryonic and larval characters, most often using as examples his favourite animals, the cirripedes. Then I discuss remaining problems, and also perspectives, to address the link between phylogeny and development in the modern terms of molecular and cladistic phylogenetics and of molecular and genetic developmental biology.     

Assessment of bioburden on human and animal tissues: Part 1—Results of method development and validation studies

Recovered human and animal tissues are used extensively in surgery for wound repair and reconstruction. In preparation for the validation of chemical disinfection and radiation sterilization processes, studies were performed on the development and validation of quantitative bioburden recovery methods for human bone and soft tissue and also for porcine dermis. The use of a swab-based method was not considered due to the known poor efficiency of recovery for this technique. The “exhaustive extraction” and “inoculated product” approaches to validation of a bioburden recovery efficiency factor have inherent strengths and weaknesses; in this study, tissues were inoculated and also subjected to a series of extractions to determine if/when “exhaustion” occurred. Femoral and tibial shaft rings, iliac crest wedges, sections of Achilles tendon, a soft tissue composite sample, and porcine dermis, were inoculated at several sites with Bacillus atrophaeus spores, and then subjected to either shaking by hand, mechanical shaking, or sonication plus mechanical shaking. Each of these methods of agitation were performed in combination with three rinse (extraction) fluids: phosphate buffer (Butterfield’s buffer), phosphate buffer with 0.2% polysorbate 80 (a surfactant), and water with 1% peptone and 1% polysorbate 80 (Fluid D). The highest recovery efficiencies were observed with sonication plus mechanical shaking; of the three extraction media, Fluid D gave the highest first-rinse recovery efficiency (65%) and Butterfield’s buffer gave the lowest (39%). Each of the three recovery methods, however appeared to reach “exhaustion”, a subsequent rinse giving less than 10% of the recovery found in the first rinse. The results demonstrated the importance of performing bioburden method development and validation studies. The method validation strategy described here, using a combination of tissue inoculation and repetitive extraction, showed the superiority of sonication plus mechanical shaking using Fluid D as the rinse medium. In addition, the use of only the exhaustive extraction approach could have resulted in the development of a methodology that consistently underestimated the bioburden present on/in recovered tissue.     

Implications of reiterative DNA—Metal ion complexes in the induction and development of neoplastic cells

Experimental data on the content in metal ions of DNA preparations from various neoplastic and healthy tissues are summarized: metal ions are preferentially bound to reiterative DNA sequences, where they may induce conformational variations and thus modify the binding of effector molecules such as repressors and polymerases. A model is described where essential and toxic metals are successively loaded on ligand acceptor groups of increasing affinity and thus may reach the final active sites: enzymes and reiterative DNA sequences (equated at least partially to regulative DNA sequences). The effects of some molecules, including peptides, antibiotics, growth factors, hormones, and antineoplastic substances, on DNA conformation could be explained in part by their chelating ability. The neoplastic state may be induced by a modification of metal ion transfer chains: quantitatively by a continuous derepression of genes coding for metal ligands, genes that are only temporarily derepressed during development in normal cells, and qualitatively by modifications of the nucleotidic sequence of structural genes leading to an increase of the chelating ability of the coded metal ligand.