3. Taxonomy and classification of Algae
... protozoan organism into a food vesicle. Instead of being digested as a source of food, the cyanobacterium lived as an endosymbiont in the protozoan. This event benefited the protozoan because it received some of the photosynthate from the endosymbiotic alga, and it benefited the cyanobacterium becau ...
... protozoan organism into a food vesicle. Instead of being digested as a source of food, the cyanobacterium lived as an endosymbiont in the protozoan. This event benefited the protozoan because it received some of the photosynthate from the endosymbiotic alga, and it benefited the cyanobacterium becau ...
Cell cycle: Checkpoint proteins and kinetochores
... signal emanating from kinetochores that are not attached to the spindle apparatus [12]. Genetic studies in yeast have identified some of the molecules involved in the spindle assembly checkpoint. Like vertebrate cells, budding yeast cells arrest in mitosis in response to spindle depolymerization [13 ...
... signal emanating from kinetochores that are not attached to the spindle apparatus [12]. Genetic studies in yeast have identified some of the molecules involved in the spindle assembly checkpoint. Like vertebrate cells, budding yeast cells arrest in mitosis in response to spindle depolymerization [13 ...
Cooperative Function of Upstream and Core Domains of the Yeast
... initiation step, and the upstream and core domains are both necessary for transcription initiation complex formation. The upstream domain of the promoter, however, can be severed from the core promoter domain once the stable complex has been formed. These results suggest that the yeast ribosomal gen ...
... initiation step, and the upstream and core domains are both necessary for transcription initiation complex formation. The upstream domain of the promoter, however, can be severed from the core promoter domain once the stable complex has been formed. These results suggest that the yeast ribosomal gen ...
Therapeutic Potential of miR-3189-3p Against Glioblastoma Selby White , Duane Jeansonne
... poorly to standard radio- and chemo-treatments. MicroRNAs are short single-stranded non-coding RNAs that regulate gene expression in both normal and pathological conditions. Using in vitro and in vivo models we have previously found that miR-3189-3p has anti-tumoral activity against glioblastoma thr ...
... poorly to standard radio- and chemo-treatments. MicroRNAs are short single-stranded non-coding RNAs that regulate gene expression in both normal and pathological conditions. Using in vitro and in vivo models we have previously found that miR-3189-3p has anti-tumoral activity against glioblastoma thr ...
OF PISUM SATIVUM L. (a) Source of Material
... Fig. 3). As time progressed these coalesced so that each cell contained several large vacuoles by the end of phase 2. This differentiation and expansion of the vacuolar system coincided with the expansion of the cells. The long axis of the plastids increased from about 3 fk to 8 fk during phase 2. T ...
... Fig. 3). As time progressed these coalesced so that each cell contained several large vacuoles by the end of phase 2. This differentiation and expansion of the vacuolar system coincided with the expansion of the cells. The long axis of the plastids increased from about 3 fk to 8 fk during phase 2. T ...
Role of the spindle pole body of yeast in mediating assembly of the
... proteins that are speci®c for SPBs of meiotic cells, we analyzed genes that are transcriptionally upregulated during meiosis (Chu et al., 1998) for sequences predicted to code for coiled-coil domains (Lupas et al., 1991). A number of candidate genes could be identi®ed (18 genes in total). To determi ...
... proteins that are speci®c for SPBs of meiotic cells, we analyzed genes that are transcriptionally upregulated during meiosis (Chu et al., 1998) for sequences predicted to code for coiled-coil domains (Lupas et al., 1991). A number of candidate genes could be identi®ed (18 genes in total). To determi ...
Localization of Phospholamban in Smooth Muscle
... such as Western blots. Labeling of the SR in smooth muscle tissue appears to form distinct patches while the SR of canine cardiac tissue is uniformly labeled (unpublished data) in agreement with previous observations (8). A similar "patchy" labeling pattern was also observed when SR vesicles isolate ...
... such as Western blots. Labeling of the SR in smooth muscle tissue appears to form distinct patches while the SR of canine cardiac tissue is uniformly labeled (unpublished data) in agreement with previous observations (8). A similar "patchy" labeling pattern was also observed when SR vesicles isolate ...
Import of Agrobacterium T-DNA into Plant Nuclei: Two
... To study the mechanism of nuclear import of T-DNA, complexes consisting of the virulence proteins VirD2 and VirE2 as well as single-stranded DNA (ssDNA) were tested for import into plant nuclei in vitro. Import of these complexes was fast and efficient and could be inhibited by a competitor, a nucle ...
... To study the mechanism of nuclear import of T-DNA, complexes consisting of the virulence proteins VirD2 and VirE2 as well as single-stranded DNA (ssDNA) were tested for import into plant nuclei in vitro. Import of these complexes was fast and efficient and could be inhibited by a competitor, a nucle ...
The basement membrane anchors epithelium to the
... The primary function of the basement membrane is to anchor down the epithelium to its loose connective tissue underneath. This is achieved by cell-matrix adhesions through substrate adhesion molecules (SAMs). The basement membrane also acts as a mechanical barrier, preventing malignant cells from in ...
... The primary function of the basement membrane is to anchor down the epithelium to its loose connective tissue underneath. This is achieved by cell-matrix adhesions through substrate adhesion molecules (SAMs). The basement membrane also acts as a mechanical barrier, preventing malignant cells from in ...
Cryoelectron Tomography: Implications for Actin Cytoskeleton
... verity of postfixation, dehydration, and embedding required for thin-section electron microscopy.1 Single filaments or more loosely interconnected filament networks, either purified or examined in situ, are very sensitive to these procedures. Meshworks of actin filaments found in lamellipodia are pa ...
... verity of postfixation, dehydration, and embedding required for thin-section electron microscopy.1 Single filaments or more loosely interconnected filament networks, either purified or examined in situ, are very sensitive to these procedures. Meshworks of actin filaments found in lamellipodia are pa ...
Cytoskeleton-Plasma Membrane-Cell Wall
... and Gunning, 2000). In contrast, most animal and human cells are truly “naked” and interact with the ECM in its vicinity that is often produced by other cells, occasionally at discrete domains known as focal adhesions (Critchley, 2000) or tight/adherens junctions and desmosomes in the case of cell-t ...
... and Gunning, 2000). In contrast, most animal and human cells are truly “naked” and interact with the ECM in its vicinity that is often produced by other cells, occasionally at discrete domains known as focal adhesions (Critchley, 2000) or tight/adherens junctions and desmosomes in the case of cell-t ...
The Role of Cytoskeletal Elements in Shaping Bacterial Cells
... is now recognized as the property more relevant for their cellular activities [45, 61]. Bactofilins and Other Cytoskeletal Elements Recently, another group of filament-forming proteins, named as bactofilins, have been identified among all major phyla of bacteria [50]. Bactofilins from Caulobacter cr ...
... is now recognized as the property more relevant for their cellular activities [45, 61]. Bactofilins and Other Cytoskeletal Elements Recently, another group of filament-forming proteins, named as bactofilins, have been identified among all major phyla of bacteria [50]. Bactofilins from Caulobacter cr ...
Chromatin plasticity in pluripotent cells
... transcriptional activity. Bearing in mind that pluripotency is no more (and no less) than the potential to become any cell type, gene expression in pluripotent cells can be viewed as a ‘catalogue’ and transcriptional activity as an open ‘index’ awaiting a choice of ‘product/service’ to be made in or ...
... transcriptional activity. Bearing in mind that pluripotency is no more (and no less) than the potential to become any cell type, gene expression in pluripotent cells can be viewed as a ‘catalogue’ and transcriptional activity as an open ‘index’ awaiting a choice of ‘product/service’ to be made in or ...
Separate metabolic pathways leading to DNA fragmentation and
... wo types of cell death, referred to as apoptosis and necrosis, have usually been described (1-5). Apoptosis, T in which the cell actively participates in its demise, is characterized by interuucleosomal DNA fragmentation, chromatin condensation, and cytoplasmic blebbing. At the early stages of this ...
... wo types of cell death, referred to as apoptosis and necrosis, have usually been described (1-5). Apoptosis, T in which the cell actively participates in its demise, is characterized by interuucleosomal DNA fragmentation, chromatin condensation, and cytoplasmic blebbing. At the early stages of this ...
Formins: Linking Cytoskeleton and Endomembranes in Plant Cells
... especially among proteins that can associate with membranes on one hand and bind to microfilaments, microtubules, or even both cytoskeletal systems, on the other. Formins, or FH2 proteins, are an example of such a protein family. In this review we summarize the observations from both opisthokont (fu ...
... especially among proteins that can associate with membranes on one hand and bind to microfilaments, microtubules, or even both cytoskeletal systems, on the other. Formins, or FH2 proteins, are an example of such a protein family. In this review we summarize the observations from both opisthokont (fu ...
Molecular encounters at microtubule ends in the plant cell cortex
... expression of Arabidopsis g-tubulin in fission yeast (Schizosaccharomyces pombe) lacking endogenous g-tubulin. Arabidopsis g-tubulin was properly targeted to MTOCs and able to nucleate MTs in fission yeast [5]. In plant cells, g-tubulin was not restricted to MT ends as expected but seen as a punctat ...
... expression of Arabidopsis g-tubulin in fission yeast (Schizosaccharomyces pombe) lacking endogenous g-tubulin. Arabidopsis g-tubulin was properly targeted to MTOCs and able to nucleate MTs in fission yeast [5]. In plant cells, g-tubulin was not restricted to MT ends as expected but seen as a punctat ...
Protein Synthesis and Quality Control at the Endoplasmic Reticulum
... movement of many small ions and molecules across the membrane? There are many examples of the need to maintain a membrane’s permeability barrier during protein trafficking. More than 90% of mitochondrial proteins are synthesized by cytoplasmic ribosomes and then imported into mitochondria [4,5]. Sin ...
... movement of many small ions and molecules across the membrane? There are many examples of the need to maintain a membrane’s permeability barrier during protein trafficking. More than 90% of mitochondrial proteins are synthesized by cytoplasmic ribosomes and then imported into mitochondria [4,5]. Sin ...
Proteobacteria as the Origin of Eukaryotes: The Syntrophic Hypothesis
... 1991). Among other mechanistic difficulties, this hypothesis fails to explain the origin of the nuclear membrane. A previous model attempting to overcome this problem had already been proposed by Cavalier-Smith, suggesting that the origin of this structure was the fusion of cytoplasmic cisternae (Ca ...
... 1991). Among other mechanistic difficulties, this hypothesis fails to explain the origin of the nuclear membrane. A previous model attempting to overcome this problem had already been proposed by Cavalier-Smith, suggesting that the origin of this structure was the fusion of cytoplasmic cisternae (Ca ...
the peroxisomal endomembrane system and the role of the ER
... of the peroxisome were synthesized cotranslationally on the ER (Beevers, 1979). These nascent proteins were proposed to then be sequestered into an expanding vesicle that would eventually bud from the ER to produce a mature, functional peroxisome (Beevers, 1979). However, subsequent observations sug ...
... of the peroxisome were synthesized cotranslationally on the ER (Beevers, 1979). These nascent proteins were proposed to then be sequestered into an expanding vesicle that would eventually bud from the ER to produce a mature, functional peroxisome (Beevers, 1979). However, subsequent observations sug ...
Separate Metabolic Pathways Leading to DNA Fragmentation
... wo types of cell death, referred to as apoptosis and necrosis, have usually been described (1-5). Apoptosis, T in which the cell actively participates in its demise, is characterized by interuucleosomal DNA fragmentation, chromatin condensation, and cytoplasmic blebbing. At the early stages of this ...
... wo types of cell death, referred to as apoptosis and necrosis, have usually been described (1-5). Apoptosis, T in which the cell actively participates in its demise, is characterized by interuucleosomal DNA fragmentation, chromatin condensation, and cytoplasmic blebbing. At the early stages of this ...
The cortical cytoskeletal network and cell-wall
... deposition and orientation of cellulose microfibrils in the cell wall (Paredez et al., 2006; Desprez et al., 2007; Lloyd and Chan, 2008; Crowell et al., 2009; Gutierrez et al., 2009; Shaw, 2013). (2) Microtubules also form the spindle apparatus during mitosis (Zhang and Dawe, 2011). (3) In somatic c ...
... deposition and orientation of cellulose microfibrils in the cell wall (Paredez et al., 2006; Desprez et al., 2007; Lloyd and Chan, 2008; Crowell et al., 2009; Gutierrez et al., 2009; Shaw, 2013). (2) Microtubules also form the spindle apparatus during mitosis (Zhang and Dawe, 2011). (3) In somatic c ...
Drosophila Importin-a2 Is Involved in Synapse, Axon and Muscle
... Nuclear import is required for communication between the cytoplasm and the nucleus and to enact lasting changes in gene transcription following stimuli. Binding to an Importin-a molecule in the cytoplasm is often required to mediate nuclear entry of a signaling protein. As multiple isoforms of Impor ...
... Nuclear import is required for communication between the cytoplasm and the nucleus and to enact lasting changes in gene transcription following stimuli. Binding to an Importin-a molecule in the cytoplasm is often required to mediate nuclear entry of a signaling protein. As multiple isoforms of Impor ...
Cell nucleus
In cell biology, the nucleus (pl. nuclei; from Latin nucleus or nuculeus, meaning kernel) is a membrane-enclosed organelle found in eukaryotic cells. Eukaryotes usually have a single nucleus, but a few cell types have no nuclei, and a few others have many.Cell nuclei contain most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these chromosomes are the cell's nuclear genome. The function of the nucleus is to maintain the integrity of these genes and to control the activities of the cell by regulating gene expression—the nucleus is, therefore, the control center of the cell. The main structures making up the nucleus are the nuclear envelope, a double membrane that encloses the entire organelle and isolates its contents from the cellular cytoplasm, and the nucleoskeleton (which includes nuclear lamina), a network within the nucleus that adds mechanical support, much like the cytoskeleton, which supports the cell as a whole.Because the nuclear membrane is impermeable to large molecules, nuclear pores are required that regulate nuclear transport of molecules across the envelope. The pores cross both nuclear membranes, providing a channel through which larger molecules must be actively transported by carrier proteins while allowing free movement of small molecules and ions. Movement of large molecules such as proteins and RNA through the pores is required for both gene expression and the maintenance of chromosomes. The interior of the nucleus does not contain any membrane-bound sub compartments, its contents are not uniform, and a number of sub-nuclear bodies exist, made up of unique proteins, RNA molecules, and particular parts of the chromosomes. The best-known of these is the nucleolus, which is mainly involved in the assembly of ribosomes. After being produced in the nucleolus, ribosomes are exported to the cytoplasm where they translate mRNA.