In Vitro Assays Demonstrate That Pollen Tube Organelles Use
... Moscatelli et al., 1998). More recently, a 90-kD kinesinrelated protein (90-kD ATP–microtubule-associated protein [ATP-MAP]) showing motor activity was found in association with organelles and microtubules in the cortical region of pollen tubes (Cai et al., 2000), which suggested that the 90kD motor ...
... Moscatelli et al., 1998). More recently, a 90-kD kinesinrelated protein (90-kD ATP–microtubule-associated protein [ATP-MAP]) showing motor activity was found in association with organelles and microtubules in the cortical region of pollen tubes (Cai et al., 2000), which suggested that the 90kD motor ...
The metabolite transporters of the plastid envelope
... The engulfment of a photoautotrophic cyanobacterium by a primitive mitochondria-bearing eukaryote traces back to more than 1.2 billion years ago. This single endosymbiotic event not only provided the early petroalgae with the metabolic capacity to perform oxygenic photosynthesis, but also introduced ...
... The engulfment of a photoautotrophic cyanobacterium by a primitive mitochondria-bearing eukaryote traces back to more than 1.2 billion years ago. This single endosymbiotic event not only provided the early petroalgae with the metabolic capacity to perform oxygenic photosynthesis, but also introduced ...
Cell Wall, Cytoskeleton, and Cell Expansion in Higher Plants
... Since the growth rate of a given cell is not strictly correlated with the orientation of its microtubules or cellulose microfibrils, a broader approach that investigates the behavior of microtubules and cellulose microfibrils between neighboring cells or within inner tissue layers rather than within ...
... Since the growth rate of a given cell is not strictly correlated with the orientation of its microtubules or cellulose microfibrils, a broader approach that investigates the behavior of microtubules and cellulose microfibrils between neighboring cells or within inner tissue layers rather than within ...
arc6, an extreme chloroplast division mutant of Arabidopsis also
... out the cytoplasm and in wild-type cells often form a distinct ring around the nucleus (Fig. 2D). In arc6, the extremely large proplastids appear to be wrapped around the nucleus (Fig. 2C). In very marked contrast to the ellipsoidal wild-type proplastids the profiles of arc6 proplastids in the three ...
... out the cytoplasm and in wild-type cells often form a distinct ring around the nucleus (Fig. 2D). In arc6, the extremely large proplastids appear to be wrapped around the nucleus (Fig. 2C). In very marked contrast to the ellipsoidal wild-type proplastids the profiles of arc6 proplastids in the three ...
(Solanum tuberosum L.) plantlets to gradient saline stress
... productivity of field crops. Compared to field plants, test tube plantlets offer a direct and fast approach to investigate the mechanism of salt tolerance. Here we examined the ultrastructural and physiological responses of potato (Solanum tuberosum L. c.v. “Longshu No. 3”) plantlets to gradient sal ...
... productivity of field crops. Compared to field plants, test tube plantlets offer a direct and fast approach to investigate the mechanism of salt tolerance. Here we examined the ultrastructural and physiological responses of potato (Solanum tuberosum L. c.v. “Longshu No. 3”) plantlets to gradient sal ...
1 Cell wall integrity controls root elongation via ACC Corresponding
... Aminoethoxyvinylglycine (AVG), or with silver ions (as silver thiosulfate) to block ethylene perception. While silver had no significant effect on cell length in control or isoxaben-treated roots, AVG fully restored elongation in the presence of isoxaben (Fig. 2A). Often roots treated with both isox ...
... Aminoethoxyvinylglycine (AVG), or with silver ions (as silver thiosulfate) to block ethylene perception. While silver had no significant effect on cell length in control or isoxaben-treated roots, AVG fully restored elongation in the presence of isoxaben (Fig. 2A). Often roots treated with both isox ...
Cell Division Activity during Apical Hook
... cells compared with the basal part. In addition, Cyc1B-GUS was predominantly expressed at the apical part of the hook, as determined by the number of cells expressing GUS (Fig. 2D). These results indicate that the differential growth along the apical-basal axis of the hook is, in part, due to asymme ...
... cells compared with the basal part. In addition, Cyc1B-GUS was predominantly expressed at the apical part of the hook, as determined by the number of cells expressing GUS (Fig. 2D). These results indicate that the differential growth along the apical-basal axis of the hook is, in part, due to asymme ...
The SMN Complex Is Associated with snRNPs throughout Their
... The common neurodegenerative disease spinal muscular atrophy is caused by reduced levels of the survival of motor neurons (SMN) protein. SMN associates with several proteins (Gemin2 to Gemin6) to form a large complex which is found both in the cytoplasm and in the nucleus. The SMN complex functions ...
... The common neurodegenerative disease spinal muscular atrophy is caused by reduced levels of the survival of motor neurons (SMN) protein. SMN associates with several proteins (Gemin2 to Gemin6) to form a large complex which is found both in the cytoplasm and in the nucleus. The SMN complex functions ...
Cytoplasmic and cortical reorganizations of the ascidian zygote
... 3102 F. Roegiers and others the ectopic site (reviewed by Nishida, 1997). In such experiments one presumably deletes or transfers determinants and/or functional structures residing in different cortical and cytoplasmic domains. The relocalizations in the ascidian zygote are thought to occur in two ...
... 3102 F. Roegiers and others the ectopic site (reviewed by Nishida, 1997). In such experiments one presumably deletes or transfers determinants and/or functional structures residing in different cortical and cytoplasmic domains. The relocalizations in the ascidian zygote are thought to occur in two ...
Growth Control and Cell Wall Signaling in Plants
... by XG endo-transglycosylases (XETs) (156). Given the large molecular weights of certain pectin molecules (145), it is conceivable that similar apoplastic assembly steps occur, but so far no pectin-transglycosylase activity has been demonstrated (27, 102). The high turgor pressure of plant cells (0.5 ...
... by XG endo-transglycosylases (XETs) (156). Given the large molecular weights of certain pectin molecules (145), it is conceivable that similar apoplastic assembly steps occur, but so far no pectin-transglycosylase activity has been demonstrated (27, 102). The high turgor pressure of plant cells (0.5 ...
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... mesophyll cells of Arabidopsis rosette leaves [18] to take advantage of T-DNA insertion lines, which are currently available for more than 20,000 genes in Arabidopsis (http://signal.salk.edu/index.html) [19]. Using this procedure, a large amount of protoplasts can easily be prepared from fully-expan ...
... mesophyll cells of Arabidopsis rosette leaves [18] to take advantage of T-DNA insertion lines, which are currently available for more than 20,000 genes in Arabidopsis (http://signal.salk.edu/index.html) [19]. Using this procedure, a large amount of protoplasts can easily be prepared from fully-expan ...
A cell wall reference profile for Miscanthus bioenergy crops
... which are a-galacturonate-rich polysaccharides, and are thought to consist essentially of three interconnected domains joined together by glycosidic bonds: homogalacturonan (HG), rhamnogalacturonan-I (RG-I) and rhamnogalacturonan-II (RG-II) (O’Neill et al., 1990; Fry, 2010; Atmodjo et al., 2013). HG ...
... which are a-galacturonate-rich polysaccharides, and are thought to consist essentially of three interconnected domains joined together by glycosidic bonds: homogalacturonan (HG), rhamnogalacturonan-I (RG-I) and rhamnogalacturonan-II (RG-II) (O’Neill et al., 1990; Fry, 2010; Atmodjo et al., 2013). HG ...
Rapid Structural Changes and Acidification of Guard Cell Vacuoles
... PIKfyve inhibitor inhibits plant PI3P5K activity (Figure 4A). Arabidopsis FAB1C and its conserved lipid kinase domain were expressed in bacteria, and PtdIns(3,5)P2 synthesis was examined in vitro. Both the full-length enzyme and lipid kinase domain successfully produced PtdIns(3,5)P2 from the substr ...
... PIKfyve inhibitor inhibits plant PI3P5K activity (Figure 4A). Arabidopsis FAB1C and its conserved lipid kinase domain were expressed in bacteria, and PtdIns(3,5)P2 synthesis was examined in vitro. Both the full-length enzyme and lipid kinase domain successfully produced PtdIns(3,5)P2 from the substr ...
A Role for the Cytoskeleton in Heart Looping
... looping, but during looping, FN becomes more fragmented and appears in a speckled pattern[50]. We observed the speckled FN localization during looping as well[27]. This may relate to MMP-2 activity that we observed to be an important component of looping[29]. A member of a the Ca++-dependent family ...
... looping, but during looping, FN becomes more fragmented and appears in a speckled pattern[50]. We observed the speckled FN localization during looping as well[27]. This may relate to MMP-2 activity that we observed to be an important component of looping[29]. A member of a the Ca++-dependent family ...
Regulation of the subcellular distribution of key cellular RNA
... kinase 1 (SRPK1) phosphorylates serine/arginine-rich proteins, necessary for pre-spliceosome commitment. It was found that HCMV infection progressively increased the abundance of cytoplasmic SRPK1, which is regulated by subcellular partitioning. The essential polyadenylation factor CstF-64 was simil ...
... kinase 1 (SRPK1) phosphorylates serine/arginine-rich proteins, necessary for pre-spliceosome commitment. It was found that HCMV infection progressively increased the abundance of cytoplasmic SRPK1, which is regulated by subcellular partitioning. The essential polyadenylation factor CstF-64 was simil ...
Word - The Open University
... Other proteins can attach to the sides of filaments and promote rupture of the filaments, stabilisation of the filaments, bundling of filaments, or branching by the nucleation of new filaments. An example of a filament-cleaving molecule, gelsolin, is shown in Figure 2. It is thought that gelsolin ta ...
... Other proteins can attach to the sides of filaments and promote rupture of the filaments, stabilisation of the filaments, bundling of filaments, or branching by the nucleation of new filaments. An example of a filament-cleaving molecule, gelsolin, is shown in Figure 2. It is thought that gelsolin ta ...
Antibiotic use and abuse: A threat to mitochondria and chloroplasts
... 4]. Furthermore, both mitochondria and chloroplasts have bacterial-type ribosomes that are distinct from the 80S ribosomes in the cytoplasm; for instance, all chloroplasts contain 70S ribosomes, whereas animal mitochondria have 55– 60S ribosomes and plant mitochondria have 70–80S ribosomes, dependin ...
... 4]. Furthermore, both mitochondria and chloroplasts have bacterial-type ribosomes that are distinct from the 80S ribosomes in the cytoplasm; for instance, all chloroplasts contain 70S ribosomes, whereas animal mitochondria have 55– 60S ribosomes and plant mitochondria have 70–80S ribosomes, dependin ...
Polar auxin transport and patterning
... Vein organization can be classified in several general patterns characteristic of a particular plant (Fig. 1A–D), suggesting that genetic input into the patterning system can be responsible for predictable gross changes in venation networks. However, close inspection reveals that there is considerab ...
... Vein organization can be classified in several general patterns characteristic of a particular plant (Fig. 1A–D), suggesting that genetic input into the patterning system can be responsible for predictable gross changes in venation networks. However, close inspection reveals that there is considerab ...
Polarization of the endomembrane system is an early event in fucoid
... branes, but the specific organelles labeled were not investigated. In most cell types examined, the actin cytoskeleton facilitates endocytosis [3,9]. The role of actin in polar endocytosis was examined by treatment with 30 nM Lat B, which depolymerizes actin filaments in S. compressa zygotes [8,15]. ...
... branes, but the specific organelles labeled were not investigated. In most cell types examined, the actin cytoskeleton facilitates endocytosis [3,9]. The role of actin in polar endocytosis was examined by treatment with 30 nM Lat B, which depolymerizes actin filaments in S. compressa zygotes [8,15]. ...
Endocytosis Via Caveolae
... pathway for internalization of extracellular ligands and plasma membrane components in most cell types, it has been recognized for some time that alternative, parallel uptake mechanisms also exist. These ‘clathrin-independent pathways’ have been more difficult to study; hence, detailed information i ...
... pathway for internalization of extracellular ligands and plasma membrane components in most cell types, it has been recognized for some time that alternative, parallel uptake mechanisms also exist. These ‘clathrin-independent pathways’ have been more difficult to study; hence, detailed information i ...
Studies on polar cell wall growth and antibiotic susceptibility of
... importance in ton scale production of amino acids. Apart from that, it becomes more and more important for medical studies, where it serves as model organism due to its close relation to bacteria causing several pathogens such as tuberculosis, diphtheria and leprosy. C. glutamicum, like Mycobacteriu ...
... importance in ton scale production of amino acids. Apart from that, it becomes more and more important for medical studies, where it serves as model organism due to its close relation to bacteria causing several pathogens such as tuberculosis, diphtheria and leprosy. C. glutamicum, like Mycobacteriu ...
Calcium homeostasis in plants
... changes in cytosolic Ca2+ and continue to provide insight into Ca2+-based signal transduction and Ca2+ homeostasis in plant cells. However, microelectrodes are difficult to construct and use (Miller and Sanders, 1987; Felle, 1988a,b,1989) and can only measure Ca2+ at one point in the cell. These lim ...
... changes in cytosolic Ca2+ and continue to provide insight into Ca2+-based signal transduction and Ca2+ homeostasis in plant cells. However, microelectrodes are difficult to construct and use (Miller and Sanders, 1987; Felle, 1988a,b,1989) and can only measure Ca2+ at one point in the cell. These lim ...
Structural and Functional Comparisons of Retroviral Envelope
... view of gp41 (and, thus, Env as a whole) as a type I membrane protein, with an extracellular N-terminus, a single MSD and an approximately 150 amino acid-long cytoplasmic C-terminal tail (CTT) [2]. More recent studies, however, indicate that the CTT topology may be more dynamic and complex than prev ...
... view of gp41 (and, thus, Env as a whole) as a type I membrane protein, with an extracellular N-terminus, a single MSD and an approximately 150 amino acid-long cytoplasmic C-terminal tail (CTT) [2]. More recent studies, however, indicate that the CTT topology may be more dynamic and complex than prev ...
The Golgi-Localized Arabidopsis Endomembrane
... with the cis-Golgi marker yellow fluorescent protein (YFP)SYP32 but was largely separated from the PVC marker YFPARA7 (Geldner et al., 2009) in these transgenic Arabidopsis root cells (Figure 2C), indicating that both endogenous EMP12 and GFP-EMP12 fusion are localized to the Golgi apparatus in Arabi ...
... with the cis-Golgi marker yellow fluorescent protein (YFP)SYP32 but was largely separated from the PVC marker YFPARA7 (Geldner et al., 2009) in these transgenic Arabidopsis root cells (Figure 2C), indicating that both endogenous EMP12 and GFP-EMP12 fusion are localized to the Golgi apparatus in Arabi ...
Novel role for the Lu/BCAM–spectrin interaction in actin cytoskeleton
... Spectrins exist as elongated flexible heterotetramers of 200 nm made up of two α- and β-subunits that constitute the filaments of the network, the nodes of which are cross-linked by actin filaments. In mammals, two genes encode for α-chains (αI and αII) and five for β-chains. Although αI-spectrin is ...
... Spectrins exist as elongated flexible heterotetramers of 200 nm made up of two α- and β-subunits that constitute the filaments of the network, the nodes of which are cross-linked by actin filaments. In mammals, two genes encode for α-chains (αI and αII) and five for β-chains. Although αI-spectrin is ...
Cytoplasmic streaming
Cytoplasmic streaming, also called protoplasmic streaming and cyclosis, is the directed flow of cytosol (the liquid component of the cytoplasm) and organelles around large fungal and plant cells through the mediation of actin. This movement aids in the delivery of organelles, nutrients, metabolites, genetic information, and other materials to all parts of the cell. Cytoplasmic streaming occurs along actin filaments in the cytoskeleton of the cell.Cytoplasmic streaming was first discovered in the 1830s. The scientific breakthrough assisted scientists in developing an understanding of the different roles of cells and how they function as the basic operating systems of life.This process occurs through the operation of motor proteins called myosins.These proteins use energy of adenosine triphosphate (ATP) to act as a molecular motor, which slides along actin filaments. This works in a manner that tows the organelles and other cytoplasmic contents in the same direction. Myosin proteins consist of two conjoined proteins. If one protein remains attached to the substrate, the substance acted upon by the protein, such as a microfilament, has the ability to move organelles through the cytoplasm.The green alga genus Chara and other genera in the Division Charophyta, such as Coleochaete, are thought to be the closest relatives of land plants. These haploid organisms contain some of the largest plant cells on earth, a single cell of which can reach up to 10 cm in length. The large size of these cells demands an efficient means to distribute resources, which is enabled via cytoplasmic streaming.Cytoplasmic streaming is strongly dependent upon intracellular pH and temperature. It has been observed that the effect of temperature on cytoplasmic streaming created linear variance and dependence at different high temperatures in comparison to low temperatures. This process is complicated, with temperature alterations in the system increasing its efficiency, with other factors such as the transport of ions across the membrane being simultaneously affected. This is due to cells homeostasis depending upon active transport which may be affected at some critical temperatures.In plant cells, chloroplasts may be moved around with the stream, possibly to a position of optimum light absorption for photosynthesis. The rate of motion is usually affected by light exposure, temperature, and pH levels.In reference to pH, because actin and myosin are both proteins, strong dependence on pH is expected. The optimal pH at which cytoplasmic streaming is highest, is achieved at neutral pH and decreases at both low and high pH.The flow of cytoplasm may be stopped by:Adding Lugol's iodine solutionAdding Cytochalasin D (dissolved in dimethyl sulfoxide)↑ ↑ ↑ ↑ ↑ ↑