Search results for "Phallusia"
showing 6 items of 6 documents
Phenoloxidases in ascidian hemocytes: characterization of the pro-phenoloxidase activating system.
2003
The phenoloxidase (PO) activity of the hemocytes lysate supernatant from three ascidians species, assayed by means of 3-methyl-2-benzothiazolinone hydrazone hydrochloride, have been compared. PO-containing hemocytes were identified by a cytochemical reaction and the enzymatic activity measured by a spectrophotometric assay of lysate supernatant from hemocyte populations separated on a discontinuous Percoll density gradient. In Styela plicata, the enzyme appeared to be contained in morula cells only. In Ciona intestinalis, PO activity was shown in univacuolar refractile granulocyte and granular hemocyte. In Phallusia mammillata both compartment cell and granular hemocytes were positive. Enzy…
In vitro release of lectins by Phallusia mamillata hemocytes.
1991
Abstract α-Lactose specific lectins are released from Phallusia mamillata hemocytes during short-term cultures. The molecular weight of the subunits, the immunological cross-reaction and the sugar specificity suggest that the released lectins are similar to those isolated from the sonicated hemocytes. Because lectin release appears to take place independently of active protein synthesis, the possibility exists that lectins are pre-formed, stored in hemocytes and released when in vitro conditions stimulate the cells.
Sugar specific cellular lectins of Phallusia mamillata hemocytes: Purification, characterization and evidence for cell surface localization
1989
Cellular lectins (CLs) of Phallusia mamillata were demonstrated in protein preparations obtained by salt fractionation from hemocytes sonicated in a suitable medium. Since the lectins from the precipitated fraction bind sugars containing D-galactosyl groups, they were purified by affinity chromatography on Sepharose. SDS-PAGE under reducing conditions showed that CLs are formed of two components of apparent MWs approximately 36,900 and 35,090 and thus differ from serum lectins (SLs) (MW about 62,200). The "shrinkage" observed when SLs were examined under nonreducing conditions suggest the presence of intrachain disulphide bonds which can affect the molecular structure of the SLs. CL-SL diff…
Ricerche sulla induzione del sistema nervoso nelle larve delle Ascidie
1959
Summary Phallusia mamillata embryos at the 8-, 16-, 32- and 61-cell stages have been deprived of determined vegetative anterior blastomeres (deriving from, the A4.1 cells), with the purpose to sec which influence is exerted by such blastomeres in the induction of the nervous system. The results have been the following. 1 — The nervous system is not yet determined at the 64-cell stage. 2 — A neurali induction can be exerted even by a few blastomeres of the 64-ccll stage, containing cither entodermic or chordal material. 3 — Such inducing blastomeres arc those which give rise to the archenteron roof of the gastrula.
In Vitro Release of Lectins From Phallusia mamillata Hemocytes After Their Fractionation on a Density Gradient
1993
Hemocytes were fractionated by centrifugation on a discontinuous Percoll density gradient from the hemolymph of Phallusia mamillata. Results obtained from microcultures of the fractionated hemocytes, sugar-inhibition experiments, SDS-PAGE, and immunoblotting indicate that “compartment cells” release cellular-type (CL) lectins that are specific for α-lactose and lactulose. The released lectins have the same properties as the CL lectins that were previously isolated from sonicated unfractionated hemocytes, but they differ in terms of some molecular and immunological properties from the lectins (SL) purified from the serum. SLs were never found in the supernatants from microcultures of the fra…
Erythrocyte agglutinins in the blood of certain Ascidians
1975
Plasma from Ciona intestinalis, Phallusia mamillata and Ascidia malaca possess hemagglutinin for a variety of erythrocytes. Results obtained by physical and chemical treatments suggest that hemagglutinin for Phallusia mamillata and Ascidia malaca may be a protein or a protein-like substance.