Here we review the present knowledge about the molecular organization of these intracellular channel regions and their role in both setting and controlling Kv voltage-dependent gating properties.
Some illustrative examples about the relevance of these cytoplasmic domains determining the possibilities for modulation of Kv channel gating by cellular components are also considered. Full Text Available In contrast to most DNA viruses, poxviruses replicate their genomes in the cytoplasm without host involvement.
We find that vaccinia virus induces cytoplasmic activation of ATR early during infection, before genome uncoating, which is unexpected because ATR plays a fundamental nuclear role in maintaining host genome integrity.
Consistent with this, pharmacological and RNAi-mediated inhibition of canonical ATR signaling suppresses genome replication.
Our study suggests that, in contrast to long-held beliefs, vaccinia recruits conserved components of the eukaryote DNA replication and repair machinery to amplify its genome in the host cytoplasm. Stabilization and Degradation Mechanisms of Cytoplasmic Ataxin Full Text Available Aggregation-prone proteins in neurodegenerative disease disrupt cellular protein stabilization and degradation pathways.
Cytoplasmic stabilization of ATXN1 by phosphorylation and mediated mechanisms ultimately drive translocation of the protein to the nucleus where aggregation may occur. However, experimental inhibition of phosphorylation and binding results in rapid degradation of ATXN1, thus preventing nuclear translocation and cellular toxicity.
The exact mechanism of cytoplasmic ATXN1 degradation is currently unknown; further investigation of degradation may provide future therapeutic targets. This review examines the present understanding of cytoplasmic ATXN1 stabilization and potential degradation mechanisms during normal and pathogenic states. Agriculture and stream water quality: A biological evaluation of erosion control practices. Agricultural runoff affects many streams in North Carolina. However, there is is little information about either its effect on stream biota or any potential mitigation by erosion control practices.
In this study, benthic macroinvertebrates were sampled in three different geographic areas of North Carolina, comparing control watersheds with well-managed and poorly managed watersheds. Agricultural streams were characterized by lower taxa richness especially for intolerant groups and low stability.
These effects were most evident at the poorly managed sites. Sedimentation was the apparent major problem, but some changes at agricultural sites implied water quality problems.
The groups most intolerant of agricultural runoff were Ephemeroptera, Plecoptera and Trichoptera. Tolerant species were usually filter-feeders or algal grazers, suggesting a modification of the food web by addition of particulate organic matter and nutrients. This study clearly indicates that agricultural runoff can severely impact stream biota.
However, this impact can be greatly mitigated by currently recommended erosion control practices. First cytoplasmic loop of glucagon-like peptide-1 receptor can function at the third cytoplasmic loop position of rhodopsin. G protein-coupled receptors GPCRs are classified into several families based on their amino acid sequences. In family 1, GPCRs such as rhodopsin and adrenergic receptor, the structure-function relationship has been extensively investigated to demonstrate that exposure of the third cytoplasmic loop is essential for selective G protein activation.
In contrast, much less is known about other families. We succeeded in expressing a mutant having the first cytoplasmic loop of GLP-1 receptor and found that this mutant activated Gi and Go efficiently but did not activate Gt. Moreover, the rhodopsin mutant having the first loop of Gs-coupled secretin receptor of family 2 decreased the Gi and Go activation efficiencies.
Therefore, the first loop of GLP-1 receptor would share a similar role to the third loop of rhodopsin in G protein activation.
This result strongly suggested that different families of GPCRs have maintained molecular architectures of their ancestral types to generate a common mechanism, namely exposure of the cytoplasmic loop, to activate peripheral G protein. Full Text Available In this study the species diversity and distribution of macrophytes in surveyed sites of middle-sized streams of Latvia were investigated. The aim of the study was to determine the composition of macrophyte vegetation in Latvian streams in relation to the environmental factors stream width, water depth, substrate type, shading and flow velocity.
On the basis of these factors, five major groups of streams were distinguished representing mutually different typical macrophyte communities — 1 fast flowing streams on gravelly and stony substrate, 2 slow flowing streams on gravelly and stony substrate, 3 fast flowing streams on sandy substrate, 4 slow flowing streams on sandy substrate, and 5 streams with soft, silty substrate. Totally, 47 macrophyte taxa were found in the streams.
The highest species richness 22 was found in slow flowing streams with gravelly substrate. Species- poor macrophyte communities were characteristic for fast flowing streams on sandy substrate. Pollen mitochondria in cytoplasmically male sterile tobacco zygotic and embryonic cells. An attempt is being made to establish cytoplasmic organelles transmission during the process of fertilization, by using tobacco grain pollen labelled with leucine 14 C and tritiated thymidine.
Through autoradiography the fate of pollen germination and its entry into the embryo sac has been studied. A few days after fertilization, labelled cytoplasmic organelles - mainly mitochondria - were detected in the embryo sac. However, labelling was not observed in cytoplasmic organelles by using tritiated thymidine.
For more conclusive results labelled DNA incorporated in cytoplasmic organelles have to be traced during the embryo and endosperm development. Colon cancer frequently results in metastasis to the liver, where it becomes the main cause of death. However, the cell cycle in primary tumors and metastases is poorly understood. HCTGFP-RFP cells subsequently formed primary tumors in the spleen, as well as metastatic colonies in the liver and retroperitoneum by 28 days after cell transplantation.
Using an Olympus FV confocal microscope, it was possible to clearly image mitosis of the dual-colored colon cancer cells in the primary tumor as well as liver and other metastases. Multi-nucleate cancer cells, in addition to mono-nucleate cancer cells and their mitosis, were observed in the primary tumor and metastasis. A similar ratio of mono-nucleate, multi-nucleate, and mitotic cells grew from the primary and metastatic tumors in culture, suggesting similarity of the nuclear- cytoplasmic dynamics of primary and metastatic cancer cells, further emphasizing the stochastic nature of metastasis.
Our results demonstrate a similar heterogeneity of nuclear- cytoplasmic dynamics within primary tumors and metastases, which may be an important factor in the stochastic nature of metastasis. John G. Delinassios , All rights reserved. Marker-assisted identification of restorer gene s in iso- cytoplasmic restorer lines of WA cytoplasm in rice and assessment of their fertility restoration potential across environments. Iso- cytoplasmic restorers possess the same male sterile cytoplasm as the cytoplasmic male sterile CMS lines, thereby minimizing the potential cyto-nuclear conflict in the hybrids.
Restoration of fertility of the wild abortive CMS is governed by two major genes namely, Rf3 and Rf4. Therefore, assessing the allelic status of these restorer genes in the iso- cytoplasmic restorers using molecular markers will not only help in estimating the efficiency of these genes either alone or in combination, in fertility restoration in the hybrids in different environments, but will also be useful in determining the efficacy of these markers.
In the present study, the efficiency of molecular markers in identifying genotypes carrying restorer allele of the gene s Rf3 and Rf4, restoring male fertility of WA cytoplasm in rice was assessed in a set of iso- cytoplasmic rice restorers using gene linked as well as candidate gene based markers.
In order to validate the efficacy of markers in identifying the restorers, a sub-set of selected 25 iso- cytoplasmic rice restorers were crossed with four different cytoplasmic male sterile lines namely, IR A, IR A, Pusa 6A and RTN 12A, and the pollen and spikelet fertility of the F 1 s were evaluated at three different locations. Marker analysis showed that Rf4 was the predominant fertility restorer gene in the iso- cytoplasmic restorers and Rf3 had a synergistic effect on fertility restoration.
It is concluded that the gene based markers can be effectively used in identifying fertility restorer lines obviating the need for making crosses and evaluating the F 1 s.
We perform a search for stellar streams around the Milky Way using the first three years of multi-band optical imaging data from the Dark Energy Survey DES. We search for stellar streams using a matched-filter in color-magnitude space derived from a synthetic isochrone of an old, metal- poor stellar population.
In addition, we report the discovery of eleven new stellar streams. In general, the new streams detected by DES are fainter, more distant, and lower surface brightness than streams detected by similar techniques in previous photometric surveys. The ever-growing sample of stellar streams will provide insight into the formation of the Galactic stellar halo, the Milky Way gravitational potential, as well as the large- and small-scale distribution of dark matter around the Milky Way.
Induction of cytoplasmic male sterility by gamma-ray and chemical mutagens in sugar beets. Cytoplasmic inheritance was confirmed by the reciprocal crossings between plants with normal phenotype from gamma-strains progeneis of the male mutants which transmitted male sterility through the mother plants and H or H The crossing experiments suggested that various kinds of cytoplasm were induced by gamma-ray irradiation, and that different nuclear genes were responsible for the respective cytoplasms.
A specific relationship between the pollen restoring genes and the sterile cytoplasms was established, and was named ''one set of pollen restoring genes for one cytoplasm ''. It is probable that the cytoplasmic mutation occurred in normal cytoplasm strains and the specific combination between the altered cytoplasm and the recessive nuclear gene produced male sterility.
Ethyl methane sulphonate, ethidium bromide, acriflavine and streptomycin were also effective in inducing cytoplasmic mutation in sugar beets. Male sterile plants appeared in the population of N cytoplasm sugar beet strains, H and H, when their dry seeds were exposed to 50 kR gamma-ray, and the male sterility was maintained up to the M 4 generation through the mother plants.
Kaihara, S. The cytoplasm of a living cell is an active environment through which intracellular components move and mix. We explore, using theoretical modeling coupled with microrheological measurements, the efficiency of particle dispersion via different modes of transport within this active environment.
In particular, we focus on the role of cytoplasmic flow over different scales in contributing to organelle transport within two different cell types. In motile neutrophil cells, we show that bulk fluid flow associated with rapid cell deformation enhances particle transport to and from the cell periphery.
In narrow fungal hyphae, localized flows due to hydrodynamic entrainment are shown to contribute to optimally efficient organelle dispersion.
Our results highlight the importance of non-traditional modes of transport associated with flow of the cytoplasmic fluid in the distribution of organelles throughout eukaryotic cells. Consequences of cytoplasmic irradiation.
Studies from microbeam. The prevailing dogma for radiation biology is that genotoxic effects of ionizing radiation such as mutations and carcinogenesis are attributed mainly to direct damage to the nucleus. However, with the development of microbeam that can target precise positions inside the cells, accumulating evidences have shown that energy deposit by radiation in nuclear DNA is not required to trigger the damage, extra-nuclear or extra-cellular radiation could induce the similar biological effects as well.
This review will summarize the biological responses after cytoplasm irradiated by microbeam, and the possible mechanisms involved in cytoplasmic irradiation. Many TRIM proteins form cytoplasmic bodies of unknown function. Full Text Available Background. It is unusual for the antineutrophil cytoplasmic antibody with cytoplasmic pattern cANCA to present in patients with inflammatory bowel disease IBD without vasculitis. The median age was 8. The most common symptoms were diarrhea, abdominal pain, weight loss, and rectal bleeding.
None had family history or clinical features suggestive of vasculitis involving renal and respiratory systems. Apart from male preponderance, there were no peculiar characteristics for the cANCA positive patients.
Actin polymerisation at the cytoplasmic face of eukaryotic nuclei. Full Text Available Abstract Background There exists abundant molecular and ultra-structural evidence to suggest that cytoplasmic actin can physically interact with the nuclear envelope NE membrane system. However, this interaction has yet to be characterised in living interphase cells. In addition, both transiently expressed fluorescent actin and cytoplasmic micro-injection of fluorescent actin resulted in accumulation of actin at the NE-membrane.
Consistent with the idea that the cytoplasmic phase of NE-membranes can support this novel pool of perinuclear actin polymerisation we show that isolated, intact, differentiated primary hepatocyte nuclei support actin polymerisation in vitro.
Further this phenomenon was inhibited by treatments hindering steric access to outer-nuclear-membrane proteins e. Conclusion We conclude that actin polymerisation occurs around interphase nuclei of living cells at the cytoplasmic phase of NE-membranes. Channel water balance and exchange with subsurface flow along a mountain headwater stream in Montana, United States.
Channel water balances of contiguous reaches along streams represent a poorly understood scale of stream -subsurface interaction. We measured reach water balances along a headwater stream in Montana, United States, during summer base flow recessions. Reach water balances were estimated from series of tracer tests in 13 consecutive reaches delineated evenly along a 2. The discovery of the serological markers known as antineutrophil cytoplasmic antibodies revolutionized the diagnosis and follow-up treatment of the various forms of pulmonary vasculitis, especially that of Wegener's granulomatosis.
The antineutrophil cytoplasmic antibodies pattern can be cytoplasmic or perinuclear. Determination of antineutrophil cytoplasmic antibodies titers aids the diagnosis and follow-up treatment of pulmonary vasculitis. Objective video quality metrics are designed to estimate the quality of experience of the end user. However, these objective metrics are usually validated with video streams degraded under common distortion types. In the presented work, we analyze the performance of published and known full Experimental results indicate not surprisingly that state of the art objective quality metrics overlook the perceived degradations in the adaptive video streams and perform poorly Raman microspectroscopy of nucleus and cytoplasm for human colon cancer diagnosis.
Subcellular Raman analysis is a promising clinic tool for cancer diagnosis, but constrained by the difficulty of deciphering subcellular spectra in actual human tissues.
We report a label-free subcellular Raman analysis for use in cancer diagnosis that integrates subcellular signature spectra by subtracting cytoplasm from nucleus spectra Nuc. Raman mapping with the classical least-squares CLS model allowed direct visualization of the distribution of the cytoplasm and nucleus. The PLS-DA model was employed to evaluate the diagnostic performance of five types of spectral datasets, including non-selective, nucleus, cytoplasm , ratio of nucleus to cytoplasm Nuc.
Discriminating between normal and cancerous cells of actual human tissues through subcellular Raman markers is feasible, especially when using the nucleus- cytoplasm difference spectra. The subcellular Raman approach had good stability, and had excellent diagnostic performance for rectal as well as colon tissues. The insights gained from this study shed new light on the general applicability of subcellular Raman analysis in clinical trials. Vegetation patterns and abundances of amphibians and small mammals along small streams in a northwestern California watershed.
Our goal was to describe and evaluate patterns of association between stream size and abundances of amphibians and small mammals in a northwestern California watershed. We sampled populations at 42 stream sites and eight upland sites within a watershed in and Stream reaches sampled ranged from poorly defined channels that rarely flowed to m-wide Diatom diversity in chronically versus episodically acidified adirondack streams.
The relationship between algal species richness and diversity, and pH is controversial. Furthermore, it is still unknown how episodic stream acidification following atmospheric deposition affects species richness and diversity.
Here we analyzed water chemistry and diatom epiphyton dynamics and showed their contrasting behavior in chronically vs. Species richness and diversity were significantly higher in the chronically acidic brown water stream , where organic acidity was significantly higher and the ratio of inorganic to organic monomeric aluminum significantly lower.
Conversely, in the episodically acidic clear water stream , the inorganic acidity and pH were significantly higher and the diatom communities were very species- poor. This suggests that episodic acidification in the Adirondacks may be more stressful for stream biota than chronic acidity.
Strong negative linear relationships between species diversity, Eunotia exigua, and dissolved organic carbon against pH were revealed after the influence of non-linear temporal trends was partialled out using a novel way of temporal modeling. In this paper, we characterize, localize, and assign a possible role to a cytoplasmic PARP in the brain of Octopus vulgaris.
PARP activity was assayed in optic lobes, supraesophageal mass, and optic nerves. The highest levels of enzyme were found in the cytoplasmic fraction. Hyper-activation of the enzyme was detected in Octopus brain after visual discrimination training. We propose that the cytoplasmic PARP plays a role in vivo to induce the cytoskeletonal reorganization that occurs during learning-induced neuronal plasticity. Streams with Strahler Stream Order. Minnesota Department of Natural Resources — Stream segments with Strahler stream order values assigned.
Curious Sex Ratios and Cytoplasmic Genes. No longer This paper is a general study of four torrential streams in the 'Black Mountain' district of South Wales. Fauna collections were made at seven collecting stations, between altitudes of and ft.
Observations were made on the chemical nature of the water, current speed and temperature. The fauna taken as a whole is rich, including about species. Of the four streams , the one flowing north has the richest fauna, which includes about species in which all the usual aquatic animal groups except the hirudinea are represented. This may be attributed to its equable temperature, abundant and uniform flow, variable gradient, adequate macroflora, and alkaline-neutral moderately calcareous water.
The streams flowing south all have very soft, acid water; their stream -beds are more uniform in gradient, they are extremely variable in flow, have a more scanty macroflora, and on sunny summer days the water temperature is high, little below the shade temperature. All have a much poorer fauna than the north-flowing stream. One has a pH of 6. The second has a pH of 6. The third southern stream is generally even more acid, pH 5. Its fauna includes 55 species of which 24 are beetles, plecoptera are very poorly represented and ephemeroptera absent.
Design and implementation of streaming media server cluster based on FFMpeg. Poor performance and network congestion are commonly observed in the streaming media single server system.
This paper proposes a scheme to construct a streaming media server cluster system based on FFMpeg. In this scheme, different users are distributed to different servers according to their locations and the balance among servers is maintained by the dynamic load-balancing algorithm based on active feedback. Furthermore, a service redirection algorithm is proposed to improve the transmission efficiency of streaming media data. The experiment results show that the server cluster system has significantly alleviated the network congestion and improved the performance in comparison with the single server system.
Transdifferentiation of epithelial cells into mesenchymal cells and myofibroblasts plays an important role in tumor progression and tissue fibrosis. Such epithelial plasticity is accompanied by dramatic reorganizations of the actin cytoskeleton, although mechanisms underlying cytoskeletal effects on epithelial transdifferentiation remain poorly understood.
This article is distributed by The American Society for Cell Biology under license from the author s. Two months after publication it is available to the public under an Attribution—Noncommercial—Share Alike 3. Influence of the Gulf Stream on the troposphere.
The Gulf Stream transports large amounts of heat from the tropics to middle and high latitudes, and thereby affects weather phenomena such as cyclogenesis and low cloud formation.
But its climatic influence, on monthly and longer timescales, remains poorly understood. In particular, it is unclear how the warm current affects the free atmosphere above the marine atmospheric boundary layer. Here we consider the Gulf Stream 's influence on the troposphere, using a combination of operational weather analyses, satellite observations and an atmospheric general circulation model.
Our results reveal that the Gulf Stream affects the entire troposphere. In the marine boundary layer, atmospheric pressure adjustments to sharp sea surface temperature gradients lead to surface wind convergence, which anchors a narrow band of precipitation along the Gulf Stream. In this rain band, upward motion and cloud formation extend into the upper troposphere, as corroborated by the frequent occurrence of very low cloud-top temperatures. These mechanisms provide a pathway by which the Gulf Stream can affect the atmosphere locally, and possibly also in remote regions by forcing planetary waves.
The identification of this pathway may have implications for our understanding of the processes involved in climate change, because the Gulf Stream is the upper limb of the Atlantic meridional overturning circulation, which has varied in strength in the past and is predicted to weaken in response to human-induced global warming in the future.
Sediment composition mediated land use effects on lowland streams ecosystems. Despite the widely acknowledged connection between terrestrial and aquatic ecosystems, the contribution of runoff to the sediment composition in lowland stream deposition zones and the subsequent effects on benthic invertebrates remain poorly understood.
The aim of this study was therefore to. Magnetite nanoparticles as reporters for microcarrier processing in cytoplasm. Reibetanz, Uta, E-mail: uta. The development and therapeutic application of drug delivery systems based on colloidal microcarriers layer-by-layer coated with biopolyelectrolytes requires the investigation of their processing inside the cell for the successful and efficient transport and release of the active agents. The present study is focused on the time-dependent multilayer decomposition and the subsequent release of active agents to the cytoplasm.
This functionalization allows the monitoring of the multilayer decomposition due to the detection of the MNP release, visualized by means of proton-induced X-ray emission PIXE by elemental distribution of Si and Fe. Detection of antineutrophil cytoplasmic antibodies ANCAs. Cytoplasmic p21 is a potential predictor for cisplatin sensitivity in ovarian cancer. It was originally described as an inhibitor of cancer cell proliferation. However, many recent studies have shown that p21 promotes tumor progression when accumulated in the cell cytoplasm.
So far, little is known about the correlation between cytoplasmic p21 and drug resistance. This study was aimed to investigate the role of p21 in the cisplatin resistance of ovarian cancer. Regulation of cytoplasmic p21 was performed through transfection of p21 siRNA, Akt2 shRNA and Akt2 constitutively active vector in the two cell lines; their effects on cisplatin-induced apoptosis were evaluated by flow cytometry.
Tumor tissue sections of clinical samples were analyzed by immunohistochemistry. Immunohistochemical analysis of clinical ovarian tumor tissues demonstrated that cytoplasmic p21 was negatively correlated with the response to cisplatin based treatment. Cytoplasmic p21 is a novel biomarker of cisplatin resistance and it may represent a potential therapeutic target for ovarian tumors that are refractory to conventional treatment. Genome-wide experiments confirm that these messenger-interacting mRNAs mimRNAs form RNA duplexes in wild-type cells and thus have potential roles in modulating the mRNA levels of their convergent gene pattern under different growth conditions.
Transcriptome analyses have revealed that convergent gene transcription can produce many 3'-overlapping mRNAs in diverse organisms. Few studies have examined the fate of 3'-complementary mRNAs in double-stranded RNA-dependent nuclear phenomena, and nothing is known about the cytoplasmic destiny of 3'-overlapping messengers or their impact on gene expression.
Here, we demonstrate that the complementary tails of 3'-overlapping mRNAs can interact in the cytoplasm and promote post-transcriptional regulatory events including no-go decay NGD in Saccharomyces cerevisiae.
We show that the post-transcriptional fate of hundreds of mimRNAs is controlled by Xrn1, revealing the extent to which this conserved 5'-3' cytoplasmic exoribonuclease plays an unexpected but key role in the post-transcriptional control of convergent gene expression. Genetic variation among the male sterile cytoplasms induced by gamma irradiation in sugar beets. In sugar beets, cytoplasmic male sterility was induced artificially by radiation treatment. In the present study, four kinds of male sterile strain made from the strain H with normal cytoplasms were used, and the mode of inheritance of the sterility maintained by these strains was confirmed.
Also the hereditary mechanism of pollen fructification recovery was studied, and the newly induced heterotypic property of sterile cytoplasms was examined in comparison with naturally found sterile strains. In each of four produced strains, the male sterility was inherited down to M 4 lines stably through mother plants, and it was presumed that the sterility was caused by highly stable cytoplasmic mutation.
In each strain, two pairs of nuclear genes took part in the recovery of pollen fructification, but the mode of action of two genes was different. It was presumed that the genes of X locus did not take effect in these induced cytoplasms. The possibility that at least four kinds of male sterile cytoplasms different from S were induced from normal cytoplasms by artificial mutation was proved indirectly. Kako, I. Malfunctions of the actin binding protein Drebrin have been implicated in various human diseases such as Alzheimer's disease, cognitive impairments, cancer, and digestive disorders, though with poorly understood mechanisms.
Taken together, our study uncovers a non-actin target binding mode for ADF-H domains, and suggests that Drebrin may regulate activities of epigenetic reader ZMYND8 via its cytoplasmic sequestration.
Lifescience Database Archive English. Show Negative regulation of cytoplasmic RNA-mediated antiviral signaling. PubmedID Title Negative r Authors Komuro A, Bamm.
Importance of the short cytoplasmic domain of the feline immunodeficiency virus transmembrane glycoprotein for fusion activity and envelope glycoprotein incorporation into virions. The mature form of the envelope Env glycoprotein of lentiviruses is a heterodimer composed of the surface SU and transmembrane TM subunits. Feline immunodeficiency virus FIV possesses a TM glycoprotein with a cytoplasmic tail of approximately 53 amino acids which is unusually short compared with that of the other lentiviral glycoproteins more than residues.
To investigate the relevance of the FIV TM cytoplasmic domain to Env-mediated viral functions, we characterized the biological properties of a series of Env glycoproteins progressively shortened from the carboxyl terminus.
All the mutant Env proteins were efficiently expressed in feline cells and processed into the SU and TM subunits. Deletion of 5 or 11 amino acids from the TM C-terminus did not significantly affect Env surface expression, fusogenic activity or Env incorporation into virions, whereas removal of 17 or 23 residues impaired Env-mediated cell-to-cell fusion.
Remarkably, deletion of the TM C-terminal 35 or 41 amino acids restored or even enhanced Env biological functions. Indeed, these mutant Env glycoproteins bearing cytoplasmic domains of 18 or 12 amino acids were found to be significantly more fusogenic than the wild-type Env and were efficiently incorporated into virions. Interestingly, truncation of the TM cytoplasmic domain to only 6 amino acids did not affect Env incorporation into virions but abrogated Env fusogenicity.
Finally, removal of the entire TM cytoplasmic tail or deletion of as many as 6 amino acids into the membrane-spanning domain led to a complete loss of Env functions.
Our results demonstrate that despite its relatively short length, the FIV TM cytoplasmic domain plays an important role in modulating Env-mediated viral functions. Full Text Available Heritable changes of phenotype arising in plant ontogenesis by the influence of environmental factors belong to the most intriguing genetic phenomena.
In addition, male-sterile plants from F2 families, which segregated-out as recessives, being transferred to greenhouse also produced male-fertile panicles.
General Article Volume 2 Issue 6 June pp How crowded is the prokaryotic cytoplasm? We consider biomacromolecular crowding within the cytoplasm of prokaryotic cells as a two-phase system of 'supercrowded' cytogel and 'dilute' cytosol; we simplify and quantify this model for a coccoid cell over a wide range of biomacromolecular crowding.
The key result shows that the supercrowded. Actin and myosin regulate cytoplasm stiffness in plant cells: a study using optical tweezers. Here, we produced cytoplasmic protrusions with optical tweezers in mature BY-2 suspension cultured cells to study the parameters involved in the movement of actin filaments during changes in cytoplasmic organization and to determine whether stiffness is an actin-related property of plant cytoplasm.
Nuclear proteins hijacked by mammalian cytoplasmic plus strand RNA viruses. Plus strand RNA viruses that replicate in the cytoplasm face challenges in supporting the numerous biosynthetic functions required for replication and propagation. Most of these viruses are genetically simple and rely heavily on co-opting cellular proteins, particularly cellular RNA-binding proteins, into new roles for support of virus infection at the level of virus-specific translation, and building RNA replication complexes.
In the course of infectious cycles many nuclear- cytoplasmic shuttling proteins of mostly nuclear distribution are detained in the cytoplasm by viruses and re-purposed for their own gain. Many mammalian viruses hijack a common group of the same factors. This review summarizes recent gains in our knowledge of how cytoplasmic RNA viruses use these co-opted host nuclear factors in new functional roles supporting virus translation and virus RNA replication and common themes employed between different virus groups.
Full Text Available The results of our experiments executed to obtain tobacco male sterile lines through interspecific hybridization are summarized.
Ten wild species from the genus Nicotiana: N. HarmanliiskaBasma HB as a donor of the nucleus. Genetic effects of cytoplasmic -nuclear interaction of the studied species are discussed.
Our results suggested that cytoplasmic male sterility CMS was expressed when the cytoplasms of the above mentioned wild Nicotiana species were combined with the nucleus of N.
The 10 sources of CMS obtained in tobacco were characterized by altered flower phenotypes. Chlorophyll is the green molecule that absorbs the energy from Sunlight. However, if the light keeps illuminating the same chloroplasts and their chlorophyll molecules, they will become saturated with photons, making them unable to function until the saturation is alleviated known as the Kautsky effect.
Chloroplasts need to be moved around to a position of optimum light absorption. Thus, the chloroplasts move into lighted regions and shaded regions, alternately. This intermittent exposure to light actually increases the photosynthetic efficiency of chloroplasts. The rate of motion is usually affected by light exposure, temperature, and pH levels. For example, during the evening or winter, the cytoplasmic streaming will slow down. Cytoplasmic streaming circulates the chloroplasts around the central vacuoles in plant cells.
This optimizes the exposure of light on every single chloroplast evenly, which can maximize the efficiency of photosynthesis. The right image is the actual cytoplasmic streaming of chloroplasts in Elodea cells.
Here is a very interesting study of cytoplasmic streaming in plant cells. Scientists compared different kinds of motor proteins called myosin XI in Arabidopsis a widely studied model organism of plants. Source: Current Opinion in Plant Biology. Structurally, plants and fungi have several common characteristics. They both have cell walls around their cells. They also have long tube-like cellular structures to build the foundation of organisms. In fungi, cells grow like filaments, called hyphae , into a network.
Fungus hyphae can be divided into individual cells by partitions called septa singular: septum. Septa are specialized cell walls that consist of many tiny pores. Cytoplasmic streaming can transport molecules through these pores across cells. This allows an efficient allocation of nutrients in multicellular fungi like molds and mushrooms. Cytoplasmic Streaming brings nutrients to flow between cells through small pores. In vascular plants including ferns, trees, and all flowering plants; not including mosses, liverworts, and hornworts , there is a vascular system that includes xylem and phloem.
Xylem transports water and minerals from roots to shoots and leaves unidirectionally. The driving force in the xylem is the negative pressure due to the water loss from the leaves. You can find this prepared slide here. Phloem transports the organic molecules between parts of the plants bidirectionally. From leaves to roots, gravity can drive the movement of organic molecules.
However, in order to deliver nutrients, like sugar, from lower to higher parts, phloem needs to spend energy and uses cytoplasmic streaming to achieve this job. Xylem and phloem are both transport vessels that combine to form a vascular bundle in higher order plants. Organic molecules like sugars produced by photosynthesis can travel up or down in phloem.
Phloem is made up of connected Sieve tubes. Between two Sieve tubes, there is a porous Sieve plate. Cytoplasmic streaming can bring molecules to flow through these small pores and move upward along the phloem.
Like we mentioned before, most human cells are relatively small and do not rely on cytoplasmic streaming. However, an exception is the oocytes immature egg cell. All living things are composed of cells, but cells are complex organisms themselves.
Every cell, whether it's part of a greater organism or a simple amoeba on its own, requires certain biological processes to function.
One of the most important of these processes is cytoplasmic streaming — also referred to as cyclosis, or cytoplasmic movement. Though the process as a whole isn't fully understood, cytoplasmic streaming is what allows nutrients and proteins to move about inside a cell. In certain single-celled organisms, it also gives the cell the ability to move. Cytoplasmic streaming, commonly referred to as cyclosis, is the process by which the fluid cytoplasm inside a given cell is moved around in currents, carrying nutrients, proteins, and organelles through the cell — and allowing certain simple single-celled organisms to move.
The mechanism as a whole isn't completely understood, but the going theory is that cyclosis is powered by a network of 'motor protein' fibers positioned just inside the cell's membrane. All cells — whether they be animal cells, plant cells, fungal cells, or single-celled organisms like amoeba or protozoa — contain a number of components crucial to that cell's continued function: Organelles process nutrients, ensure healthy cell division and keep the cell "programmed" to complete its intended function inside a body or other environment.
But these components aren't fixed to specific points inside the cell, like a human's organs are.
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