The sliding theory of cytoplasmic streaming: fifty years of
... the motive force of the flow is located within the streaming protoplasm itself or whether the driving energy is produced in the protoplasmic system not involved in the streaming so that the moving protoplasm is driven passively.’’ In characean cells, the sol endoplasm rotates in the same direction w ...
... the motive force of the flow is located within the streaming protoplasm itself or whether the driving energy is produced in the protoplasmic system not involved in the streaming so that the moving protoplasm is driven passively.’’ In characean cells, the sol endoplasm rotates in the same direction w ...
The sliding theory of cytoplasmic streaming: fifty years of progress
... the motive force of the flow is located within the streaming protoplasm itself or whether the driving energy is produced in the protoplasmic system not involved in the streaming so that the moving protoplasm is driven passively.’’ In characean cells, the sol endoplasm rotates in the same direction w ...
... the motive force of the flow is located within the streaming protoplasm itself or whether the driving energy is produced in the protoplasmic system not involved in the streaming so that the moving protoplasm is driven passively.’’ In characean cells, the sol endoplasm rotates in the same direction w ...
Actin Interacting Protein1 and Actin Depolymerizing
... of Physics, Worcester Polytechnic Institute, Worcester, Massachusetts 01609 c Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts 01609 b Department ...
... of Physics, Worcester Polytechnic Institute, Worcester, Massachusetts 01609 c Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts 01609 b Department ...
Plasma Membrane Ghosts Form Differently When Produced from
... Three distinct types of cytoskeletal arrays on membrane ghosts—Using an immunofluorescent double labeling method, extensive actin and microtubule arrays can be visualized on tobacco BY-2 suspension culture cell membrane ghosts (Collings et al. 1998). Based on both actin and microtubule arrangements, ...
... Three distinct types of cytoskeletal arrays on membrane ghosts—Using an immunofluorescent double labeling method, extensive actin and microtubule arrays can be visualized on tobacco BY-2 suspension culture cell membrane ghosts (Collings et al. 1998). Based on both actin and microtubule arrangements, ...
Physiology Review Sheet
... o connects thick filaments o myofilaments thin filament – actin G-actin (globular) F-actin (filamentous) o 2 strands of F-actin forming a double helix (string of pearls) in muscle Tropomyosin o lies along actin groove o covers myosin binding sites during low Ca2+ levels Troponin o TnT – bi ...
... o connects thick filaments o myofilaments thin filament – actin G-actin (globular) F-actin (filamentous) o 2 strands of F-actin forming a double helix (string of pearls) in muscle Tropomyosin o lies along actin groove o covers myosin binding sites during low Ca2+ levels Troponin o TnT – bi ...
A role for actin in regulating apoptosis/programmed cell death
... cytoskeleton, which typically comprises filamentous networks of actin, microtubule and intermediate filaments. The assembly of actin into higher-order structures in response to environmental cues is co-ordinated members of the Rho family of GTPases, the best studies being Rho, Rac and Cdc42 (cell di ...
... cytoskeleton, which typically comprises filamentous networks of actin, microtubule and intermediate filaments. The assembly of actin into higher-order structures in response to environmental cues is co-ordinated members of the Rho family of GTPases, the best studies being Rho, Rac and Cdc42 (cell di ...
PI3K and Rho GTPase activity are required for exogenous PIP3
... 1. Ras is activated downstream of the cAMP receptor rapidly (less than 5 seconds) and independent of cortical actin polymerization and PI3K activity (e.g. Ras is the BSPI3K in the LEGI model). 2. Ras recruits and activates a small fraction of PI3K at the plasma membrane, resulting in AKT activation ...
... 1. Ras is activated downstream of the cAMP receptor rapidly (less than 5 seconds) and independent of cortical actin polymerization and PI3K activity (e.g. Ras is the BSPI3K in the LEGI model). 2. Ras recruits and activates a small fraction of PI3K at the plasma membrane, resulting in AKT activation ...
How and why does β-actin mRNA target?
... (Edmonds et al., 1996), and in fibroblasts (Bassell et al., 1994). The EF1α implicated in β-actin binding and bundling (Yang et al., 1990; Edmonds et al., 1995) is the translationally competent form of EF1α based on enzymic activity in vitro (Yang et al., 1993). EF1α associates with actin filaments ...
... (Edmonds et al., 1996), and in fibroblasts (Bassell et al., 1994). The EF1α implicated in β-actin binding and bundling (Yang et al., 1990; Edmonds et al., 1995) is the translationally competent form of EF1α based on enzymic activity in vitro (Yang et al., 1993). EF1α associates with actin filaments ...
Nucleolus-like body of mouse oocytes contains lamin A and B and
... The nuclear lamina consists of lamins, which belong to type V intermediate filament proteins [32]. Lamins are categorized into two types, A and B, based on their biochemical and sequence characteristics. Small, yet significant fractions of both A- and B-type lamins are also present throughout the nu ...
... The nuclear lamina consists of lamins, which belong to type V intermediate filament proteins [32]. Lamins are categorized into two types, A and B, based on their biochemical and sequence characteristics. Small, yet significant fractions of both A- and B-type lamins are also present throughout the nu ...
Characterization of the Enzymatic Component of the ADP
... actin from platelet cytosol (Fig. 4A) and skeletal muscle actin (Fig. 4B), these proteins were enzymatically active. By contrast, E428Q, E430Q, S388A, and R345K mutants of CDTa showed no or significantly reduced labeling of actin, indicating that these mutants had no or largely reduced ADP-ribosyltr ...
... actin from platelet cytosol (Fig. 4A) and skeletal muscle actin (Fig. 4B), these proteins were enzymatically active. By contrast, E428Q, E430Q, S388A, and R345K mutants of CDTa showed no or significantly reduced labeling of actin, indicating that these mutants had no or largely reduced ADP-ribosyltr ...
Arabidopsis Formin3 Directs the Formation of Actin
... was proposed to act as a processive actin-promoting motor (Kovar and Pollard, 2004; Romero et al., 2004; Kovar et al., 2006). Formins are characterized by the presence of conserved formin homologous domains, FH1 and FH2, which are required and sufficient for actin nucleation. The FH1 domain contains ...
... was proposed to act as a processive actin-promoting motor (Kovar and Pollard, 2004; Romero et al., 2004; Kovar et al., 2006). Formins are characterized by the presence of conserved formin homologous domains, FH1 and FH2, which are required and sufficient for actin nucleation. The FH1 domain contains ...
T Molecular Basis of Muscle Structure C 12
... myofibrillar defects similar to those described for MHC null heterozygotes.24 RLC has been shown to undergo multiple phosphorylations during the final stages of IFM development, at or near eclosion.25 Replacement of two RLC serines that are phosphorylated by myosin light chain kinase (MLCK) with ala ...
... myofibrillar defects similar to those described for MHC null heterozygotes.24 RLC has been shown to undergo multiple phosphorylations during the final stages of IFM development, at or near eclosion.25 Replacement of two RLC serines that are phosphorylated by myosin light chain kinase (MLCK) with ala ...
The Forces Behind Cell Movement
... adhesion molecules gathered in the extending region help attach the leading edge to the substrate. Cell-substrate attachments are created at the leading edge when actin bundles link the cytoskeleton to the substrate at certain sites via adhesion molecules (Figure 2). These attachments prevent the pr ...
... adhesion molecules gathered in the extending region help attach the leading edge to the substrate. Cell-substrate attachments are created at the leading edge when actin bundles link the cytoskeleton to the substrate at certain sites via adhesion molecules (Figure 2). These attachments prevent the pr ...
Pollen Tube Growth Oscillations and Intracellular
... formerly midlevel rate of growth (Fig. 1, A and B). This condition of basal, nonoscillating growth can be sustained for 10 min; if the pollen tube is retained in 2 nM Lat-B, cell extension will eventually stop completely after 30 min (Fig. 1B). Of particular note, these effects are completely revers ...
... formerly midlevel rate of growth (Fig. 1, A and B). This condition of basal, nonoscillating growth can be sustained for 10 min; if the pollen tube is retained in 2 nM Lat-B, cell extension will eventually stop completely after 30 min (Fig. 1B). Of particular note, these effects are completely revers ...
Modulation of T cell signaling by the actin cytoskeleton
... Fig. 1. Schematic diagrams of the immunological synapse at the junction between a T cell and an antigen-presenting cell (APC). (A) T cell activation leads to large-scale protein segregation in the immunological synapse, which is a specialized cell–cell junction. (B) Proteins are translocated and dif ...
... Fig. 1. Schematic diagrams of the immunological synapse at the junction between a T cell and an antigen-presenting cell (APC). (A) T cell activation leads to large-scale protein segregation in the immunological synapse, which is a specialized cell–cell junction. (B) Proteins are translocated and dif ...
Live Cell Imaging Reveals Structural Associations
... Figure 2. Coalignment between Cortical AFs and MTs in Arabidopsis Hypocotyl Cells. (A) to (C) Dual-labeled GFP:FABD (A) and mCherry:TUA5 (B), and merge of A and B (C), observed in hypocotyl cells of 3-d-old etiolated seedlings. Carets enclose regions of co-occurrence of the two channels. (D) Selecte ...
... Figure 2. Coalignment between Cortical AFs and MTs in Arabidopsis Hypocotyl Cells. (A) to (C) Dual-labeled GFP:FABD (A) and mCherry:TUA5 (B), and merge of A and B (C), observed in hypocotyl cells of 3-d-old etiolated seedlings. Carets enclose regions of co-occurrence of the two channels. (D) Selecte ...
Sampathkumar-2011-Live Cell Imaging Re - Max
... Figure 2. Coalignment between Cortical AFs and MTs in Arabidopsis Hypocotyl Cells. (A) to (C) Dual-labeled GFP:FABD (A) and mCherry:TUA5 (B), and merge of A and B (C), observed in hypocotyl cells of 3-d-old etiolated seedlings. Carets enclose regions of co-occurrence of the two channels. (D) Selecte ...
... Figure 2. Coalignment between Cortical AFs and MTs in Arabidopsis Hypocotyl Cells. (A) to (C) Dual-labeled GFP:FABD (A) and mCherry:TUA5 (B), and merge of A and B (C), observed in hypocotyl cells of 3-d-old etiolated seedlings. Carets enclose regions of co-occurrence of the two channels. (D) Selecte ...
Actin as target for modification by bacterial protein toxins
... At least three groups of toxins ⁄ effectors can be identified, which directly modify actin molecules. One group of toxins ⁄ effectors causes ADP-ribosylation of actin at arginine-177, thereby inhibiting actin polymerization. Members of this group are numerous binary actin–ADP-ribosylating exotoxins ( ...
... At least three groups of toxins ⁄ effectors can be identified, which directly modify actin molecules. One group of toxins ⁄ effectors causes ADP-ribosylation of actin at arginine-177, thereby inhibiting actin polymerization. Members of this group are numerous binary actin–ADP-ribosylating exotoxins ( ...
Get PDF file - Botanik in Bonn
... environmental signals and requirements. The arrangement and properties of the cytoskeleton are known to be regulated by associated proteins that bind either to monomeric or polymerized cytoskeletal proteins. The number of well studied and characterized cytoskeletonregulating proteins in plant cells ...
... environmental signals and requirements. The arrangement and properties of the cytoskeleton are known to be regulated by associated proteins that bind either to monomeric or polymerized cytoskeletal proteins. The number of well studied and characterized cytoskeletonregulating proteins in plant cells ...
Regulation of Tcell receptor signaling by the actin cytoskeleton and
... the receptor complex is converted into a biochemical change, such as through exposure of a phosphorylation site (9, 10), to trigger signalosome formation. This would allow TCRs to couple signal generation to the mechanical energy of the actin cytoskeleton. In the kinetic segregation mechanism of tri ...
... the receptor complex is converted into a biochemical change, such as through exposure of a phosphorylation site (9, 10), to trigger signalosome formation. This would allow TCRs to couple signal generation to the mechanical energy of the actin cytoskeleton. In the kinetic segregation mechanism of tri ...
pdf: Rahman et al. 2007.
... photolysis from blue and ultraviolet light; therefore, all experiments reported here used plants grown in yellow light, which prolongs the lifetime of IAA in growth media (Stasinopoulos and Hangarter, 1990). To characterize the mechanism of inhibition of root elongation by auxin, we pursued a kinema ...
... photolysis from blue and ultraviolet light; therefore, all experiments reported here used plants grown in yellow light, which prolongs the lifetime of IAA in growth media (Stasinopoulos and Hangarter, 1990). To characterize the mechanism of inhibition of root elongation by auxin, we pursued a kinema ...
Actin Dynamics in Muscle Cells
... generation of contraction. In non-muscle cells, actin filaments are very dynamic and regulated by an array of proteins that interact with actin filaments and/or monomeric actin. Interestingly, in non-muscle cells the barbed ends of the filaments are the predominant assembly place, whereas in muscle cel ...
... generation of contraction. In non-muscle cells, actin filaments are very dynamic and regulated by an array of proteins that interact with actin filaments and/or monomeric actin. Interestingly, in non-muscle cells the barbed ends of the filaments are the predominant assembly place, whereas in muscle cel ...
Millius et al., J. Cell Sci., 2012 - Cardiovascular Research Institute
... within 1 mm of the leading edge (Fig. 2G,H). The distribution of p40 might be more restricted than either actin or WAVE2 for several reasons: other Arp2/3 complex activators such as WASP or N-WASP in combination with WAVE2 might further bias Arp2/3 to the cell periphery, or undersampling of WAVE2 pa ...
... within 1 mm of the leading edge (Fig. 2G,H). The distribution of p40 might be more restricted than either actin or WAVE2 for several reasons: other Arp2/3 complex activators such as WASP or N-WASP in combination with WAVE2 might further bias Arp2/3 to the cell periphery, or undersampling of WAVE2 pa ...
The Putative Arabidopsis Arp2/3 Complex
... pollen tubes and root hairs (Fu et al., 2001; Jones et al., 2002). Diffuse F-actin is also associated with the expanding parts of diffusely growing cells (Fu et al., 2002). The formation of both types of diffuse F-actin is dependent upon the Rho related GTPase from plant (ROP) subfamily of Rho GTPas ...
... pollen tubes and root hairs (Fu et al., 2001; Jones et al., 2002). Diffuse F-actin is also associated with the expanding parts of diffusely growing cells (Fu et al., 2002). The formation of both types of diffuse F-actin is dependent upon the Rho related GTPase from plant (ROP) subfamily of Rho GTPas ...
Actin
Actin is a globular multi-functional protein that forms microfilaments. It is found in essentially all eukaryotic cells (the only known exception being nematode sperm), where it may be present at concentrations of over 100 μM. An actin protein's mass is roughly 42-kDa and it is the monomeric subunit of two types of filaments in cells: microfilaments, one of the three major components of the cytoskeleton, and thin filaments, part of the contractile apparatus in muscle cells. It can be present as either a free monomer called G-actin (globular) or as part of a linear polymer microfilament called F-actin (filamentous), both of which are essential for such important cellular functions as the mobility and contraction of cells during cell division.Actin participates in many important cellular processes, including muscle contraction, cell motility, cell division and cytokinesis, vesicle and organelle movement, cell signaling, and the establishment and maintenance of cell junctions and cell shape. Many of these processes are mediated by extensive and intimate interactions of actin with cellular membranes. In vertebrates, three main groups of actin isoforms, alpha, beta, and gamma have been identified. The alpha actins, found in muscle tissues, are a major constituent of the contractile apparatus. The beta and gamma actins coexist in most cell types as components of the cytoskeleton, and as mediators of internal cell motility. It is believed that the diverse range of structures formed by actin enabling it to fulfill such a large range of functions is regulated through the binding of tropomyosin along the filaments.A cell’s ability to dynamically form microfilaments provides the scaffolding that allows it to rapidly remodel itself in response to its environment or to the organism’s internal signals, for example, to increase cell membrane absorption or increase cell adhesion in order to form cell tissue. Other enzymes or organelles such as cilia can be anchored to this scaffolding in order to control the deformation of the external cell membrane, which allows endocytosis and cytokinesis. It can also produce movement either by itself or with the help of molecular motors. Actin therefore contributes to processes such as the intracellular transport of vesicles and organelles as well as muscular contraction and cellular migration. It therefore plays an important role in embryogenesis, the healing of wounds and the invasivity of cancer cells. The evolutionary origin of actin can be traced to prokaryotic cells, which have equivalent proteins. Actin homologs from prokaryotes and archea polymerize into different helical or linear filaments consisting of one or multiple strands. However the in-strand contacts and nucleotide binding sites are preserved in prokaryotes and in archea. Lastly, actin plays an important role in the control of gene expression.A large number of illnesses and diseases are caused by mutations in alleles of the genes that regulate the production of actin or of its associated proteins. The production of actin is also key to the process of infection by some pathogenic microorganisms. Mutations in the different genes that regulate actin production in humans can cause muscular diseases, variations in the size and function of the heart as well as deafness. The make-up of the cytoskeleton is also related to the pathogenicity of intracellular bacteria and viruses, particularly in the processes related to evading the actions of the immune system.