Protoplasma

http://link.springer.com/journal/709

List of Papers (Total 697)

Higher sensitivity of pad2-1 and vtc2-1 mutants to cadmium is related to lower subcellular glutathione rather than ascorbate contents

Cadmium (Cd) interferes with ascorbate and glutathione metabolism as it induces the production of reactive oxygen species (ROS), binds to glutathione due to its high affinity to thiol groups, and induces the production of phytochelatins (PCs) which use glutathione as a precursor. In this study, changes in the compartment specific distribution of ascorbate and glutathione were ...

Chicken or egg—Weismann revisited

Multicellularity allows for division of labour. This requires that individual cells adopt different developmental fates. This developmental dichotomy could arise from interactions between the cells, but it could as well be produced by a formative cell division guided by a gradient of developmental determinants within the progenitor cell such that these determinants are ...

P53 protein in proliferation, repair and apoptosis of cells

The p53 protein is an important factor of many intra- and extracellular processes. This protein regulates the repair of cellular DNA and induces apoptosis. It is also responsible for the regulation of the senescence and the cell entering the subsequent stages of the cellular cycle. The protein p53 is also involved in inhibiting angiogenesis and the induction of oxidative shock. In ...

High-resolution cryo-electron microscopy on macromolecular complexes and cell organelles

Cryo-electron microscopy techniques and computational 3-D reconstruction of macromolecular assemblies are tightly linked tools in modern structural biology. This symbiosis has produced vast amounts of detailed information on the structure and function of biological macromolecules. Typically, one of two fundamentally different strategies is used depending on the specimens and their ...

Development of a quantitative Correlative Light Electron Microscopy technique to study GLUT4 trafficking

Correlative Light Electron Microscopy (CLEM) combines advantages of light microscopy and electron microscopy in one experiment to deliver information above and beyond the capability of either modality alone. There are many different CLEM techniques, each having its own special advantages but also its technical challenges. It is however the biological question that (should) drive(s) ...

Cryo-soft X-ray tomography: a journey into the world of the native-state cell

One of the ultimate aims of imaging in biology is to achieve molecular localisation in the context of the structure of cells in their native state. Here, we review the current state of the art in cryo-soft X-ray tomography (cryo-SXT), which is the only imaging modality that can provide nanoscale 3D information from cryo-preserved, unstained, whole cells thicker than 1 μm. ...

Release of single cells from the colonial oil-producing alga Botryococcus braunii by chemical treatments

We tested for chemical reagents that would be useful in preparing a large number of vital single cells from colonial Botryococcus braunii B-race, variety Showa. Among the 18 reagents assayed, glycerol and erythritol showed the highest potency for releasing single cells. Incubation in medium containing these reagents released 40–50 % single cells in 15 min. Fluorescent staining with ...

Characterization of polarity development through 2- and 3-D imaging during the initial phase of microspore embryogenesis in Brassica napus L

Isolated microspores of B. napus in culture change their developmental pathway from gametophytic to sporophytic and form embryo-like structures (ELS) upon prolonged heat shock treatment (5 days at 32 °C). ELS express polarity during the initial days of endosporic development. In this study, we focussed on the analysis of polarity development of ELS without suspensor. Fluorescence ...

A milestone in the doubled haploid pathway of cassava

This study was aimed at inducing androgenesis in cultured anthers of cassava (Manihot esculenta Crantz) to develop a protocol for the production of doubled haploids. Microspore reprogramming was induced in cassava by cold or heat stress of anthers. Since the anthers contain both haploid microspores and diploid somatic cells, it was essential to verify the origin of anther-derived ...

Co-expression of the Arabidopsis SOS genes enhances salt tolerance in transgenic tall fescue (Festuca arundinacea Schreb.)

Crop productivity is greatly affected by soil salinity; therefore, improvement in salinity tolerance of crops is a major goal in salt-tolerant breeding. The Salt Overly Sensitive (SOS) signal-transduction pathway plays a key role in ion homeostasis and salt tolerance in plants. Here, we report that overexpression of Arabidopsis thaliana SOS1+SOS2+SOS3 genes enhanced salt tolerance ...

Synergids and filiform apparatus in the sexual and apomictic dandelions from section Palustria (Taraxacum, Asteraceae)

An evolutionary trend to reduce “unnecessary costs” associated with the sexual reproduction of their amphimictic ancestors, which may result in greater reproductive success, has been observed among the obligatory apomicts. However, in the case of the female gametophyte, knowledge about this trend in apomicts is not sufficient because most of the ultrastructural studies of the ...

The problem of morphogenesis: unscripted biophysical control systems in plants

The relative simplicity of plant developmental systems, having evolved within the universal constraints imposed by the plant cell wall, may allow us to outline a consistent developmental narrative that is not currently possible in the animal kingdom. In this article, I discuss three aspects of the development of the mature form in plants, approaching them in terms of the role ...

The very many faces of presenilins and the γ-secretase complex

Presenilin is a central, catalytic component of the γ-secretase complex which conducts intramembrane cleavage of various protein substrates. Although identified and mainly studied through its role in the development of amyloid plaques in Alzheimer disease, γ-secretase has many other important functions. The complex seems to be evolutionary conserved throughout the Metazoa, but ...

ATM/ATR-dependent Tyr15 phosphorylation of cyclin-dependent kinases in response to hydroxyurea in Vicia faba root meristem cells

DNA damage or stalled replication forks activate cell cycle checkpoints. However, the regulation of metabolic pathways that are responsible for maintenance of genome integrity in plants is still largely unknown. Present research on Vicia faba root meristem cells indicates that inhibitory phosphorylation of cyclin-dependent kinases (Cdks) at Tyr15 plays a prominent role during ...

Accumulation of noncrystalline cellulose in Physarum microplasmodia

Physarum plasmodium lives as a slimy mass of protoplast in the dark fragments into small multinucleated microplasmodia (mPL) in a liquid medium. When mPL are exposed to several unfavorable environments, they transform into “spherules” with a cell wall. Using a synchronous spherule-induction system for mPL, we examined the effect of 2,6-dichlorobenzonitrile on the synthesis of ...

Immunohistochemical evaluation of cell proliferation and apoptosis markers in ovarian surface epithelial cells of cladribine-treated rats

Cladribine has been used in the treatment of hairy cell leukemia for about 30 years. In addition, the number of indications for the application of 2-CdA is constantly increasing. The treatment with cladribine, of younger persons and even children, appears to be a major factor stimulating the more exact recognition of its activities. However, till now, little has been known about ...