(n.) A lasso cell, or thread cell. See Lasso cell, under Lasso.
Example Sentences:
(1) Nematocyst capsules and everted threads from both species contained levels of glycine and proline-hydroxyproline characteristic of vertebrate collagens.
(2) Purified nematocyst capsules and threads are rich in hydroxyproline, and dissolved by disulfide reducing agents.
(3) Investigation on important medusae and the chemistry of their nematocyst venoms have been expanding.
(4) They are considered to be the principal toxins injected by C. fleckeri during nematocyst discharge and appear to be different from the C. fleckeri toxins described by other workers.
(5) A new cytolysin has been isolated from the nematocysts of the jellyfish, Rhizostoma pulmo, and named rhizolysin.
(6) A comparison of methods for preparing a jellyfish nematocyst suspension from sea nettle (Chrysaora quinquecirrha) fishing tentacles at the beachside was conducted.
(7) Evidence obtained from the osmotic behavior of nematocysts, as well as data from in vitro exchange of their cations, are consistent with a physicochemical model in which the internal osmotic pressure of nematocysts and thus their ability to discharge is governed by the cationic composition of the content and the salt concentrations in the environment.
(8) Cnidocytes, the stinging cells of cnidarians, discharge nematocysts in response to physical contact accompanied by the stimulation of specific chemoreceptors.
(9) In the tentacles, neurons with long processes contacted up to five different batteries of nematocysts.
(10) It is suggested that they may also be present as predominant components in nematocysts of other cnidarian species and thus might represent a class of compounds which is characteristic for a whole phylum of the animal kingdom.
(11) Electrophoretic characterization of nematocyst extracts allows resolution of small proline-rich polypeptides that correspond in size to the cloned sequences.
(12) The major protein component present in the capsule and thread of a sea anemone nematocyst consists of monomers of a collagen-like protein linked by disulfide bonds.
(13) First-aid measures designed to prevent additional nematocyst rupture are species-specific.
(14) One such defective strain, called nem-4, contains virtually no stenoteles, one of the four types of nematocysts present in hydra, in its tentacles.
(15) The CSMs become predisposed to initiate nematocyst discharge into static (i.e., nonvibrating) test probes in the presence of submicromolar free and conjugated N-acetylated sugars, a process referred to as sensitization.
(16) It is suggested that the high concentration of calcium in the nematocysts accounts for their staining by cobalt and morin.
(17) Crude extract prepared from isolated and purified nematocysts (stenoteles, desmonemes, isorhizas) of Hydra attenuata Pall.
(18) Contrary to some previous reports in the literature, it has been found that spirocysts normally discharge by eversion, as do nematocysts.
(19) Unlike most nematocysts, undischarged spirocyst threads bear hollow tubules rather than spines.
(20) The toxins are labile when released from nematocysts and they lose all myotoxic activity within 3 days at 5 degrees C. They can also be isolated chromatographically from crude extracts of the contents of mixed nematocysts of C. fleckeri.
Trichocyst
Definition:
(n.) A lasso cell.
Example Sentences:
(1) We had previously shown that a phosphoprotein of 63 kDa ('PP63') is rapidly and selectively dephosphorylated during synchronous (less than or equal to 1 s) trichocyst exocytosis in Paramecium cells and then rephosphorylated within less than or equal to 1 min [Zieseniss & Plattner (1985) J.
(2) Therefore, in comparison with the reported cytosolic pH (6.8), trichocysts cannot be considered as essentially acidic compartments.
(3) Distinctive features include a complex cytoskeleton which defines the cell organization and interconnects cell components; trichocysts which resemble those in other cryptoprotists; and two non-photosynthetic plastids.
(4) Crosses between members of two independent collections of Paramecium tetraurelia mutants blocked in the final membrane fusion step of trichocyst release (nd mutants) allowed us to define 13 complementation groups comprising 23 alleles.
(5) Trichocysts from mutants defective to varying degrees in trichocyst formation were subjected to similar experimental protocols.
(6) When paramecia were treated only with Ca++ and then fixed with OsO4 plus oxalate or merely with glutardialdehyde, electron scattering deposits were formed also on the inner side of the cell membrane and within the ciliary shaft (but rarely in trichocysts).
(7) Morphological evidence that supports this grouping is the layer of sacs underneath the plasma membrane in all three taxa and the identical structure of trichocysts in the apicomplexan Spiromonas and dinoflagellates.
(8) From this comparison between wild type and mutants, we conclude: (a) that the formation of parentheses is a primary differentiation of the plasma membrane, independent of the presence of trichocysts, while the secondary transformation of parentheses into circular arrays and the formation of the rosette are triggered by interaction between trichocysts and plasma membranes; and (b) that the formation of the rosette is a prerequisite for trichocyst exocytosis.
(9) The mAbs were cross-reactive with the trichocysts of P. primaurelia, P. tetraurelia, P. caudatum and P. calkinsi with some small variation in blotting patterns.
(10) The ciliate protozoan Paramecium tetraurelia produces secretory granules (trichocysts) which release needle-like structures composed of small, acidic proteins.
(11) Characteristic arrangements of membrane-intercalated particles (MIPs) occur over trichocyst docking sites: 300 nm large double rings of MIPs and a MIP rosette in the middle.
(12) Element analysis by energy dispersive x-ray microanalysis ascertained the presence of Ca and P in deposits occurring in trichocysts.
(13) Four mAbs (131C1E8, A1-3, A16-2, D7) were directed to a trio of bands of 37, 34 and 29 (x 10(3] Mr from the beaded or meshlike trichocyst body sheath.
(14) A polyclonal antibody directed against the luciferase of the luminous dinoflagellate Gonyaulax polyedra labels both dense vesicles and trichocyst sheaths, as visualized in the electron microscope after treatment of antibody-reacted sections with an immunogold probe.
(15) On the plasma membrane of Paramecium circular arrays of particles mark the sites of attachment of the tips of the intracellular secretory organelles-trichocysts.
(16) Upon release the trichocyst membrane fuses with the cell membrane and the trichocyst content undergoes a Ca2+-dependent irreversible expansion.
(17) The number of non-docked, free trichocysts in the cytoplasm is only slightly changed, indicating a continuous synthesis and docking rate (approximately 2-3 organelles per min).
(18) This mutant was chosen because it is the best known of its class to date and seems to be altered in assembly of the material connecting the trichocyst membrane to the plasma membrane and in assembly of the "rosette," a complex array of intramembranous particles in the plasma membrane at the trichocyst insertion sites.
(19) Those "resting" trichocysts which were devoid of deposits did not contain Ca or P enriched.
(20) The resulting needle-like extended trichocyst matrix (xtmx), also paracrystalline, is released outside the cell.