scholarly journals THE RELATIONSHIP OF CONCANAVALIN A BINDING TO LECTIN-INITIATED CELL AGGLUTINATION

1973 ◽  
Vol 59 (1) ◽  
pp. 134-142 ◽  
Author(s):  
Kenneth D. Noonan ◽  
Max M. Burger

We have investigated the relationship of concanavalin. A binding to the cell surface of normal and transformed cells and the subsequent agglutination of the transformed cells. At room temperature almost no differences could be detected in agglutinin binding between transformed and untransformed cells. At 0°C, however, where endocytosis was negligible, the transformed cells bound three times more agglutinin. However, transformed cells and trypsin-treated normal cells do not agglutinate at 0°C although the amounts of agglutinin bound at 0°C are sufficient to permit agglutination when such cells are shifted up to room temperature. Both transformed and trypsin-treated normal cells show a marked increase in agglutination at 15°C as compared to agglutination at 0°C. From this, as well as the observation that mild glutaraldehyde fixation of the cell surface inhibited agglutination but not agglutinin binding, it was concluded that concanavalin A-mediated cell agglutination requires free movement of the agglutinin receptor sites within the plane of the cell surface.

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Yu-An Chen ◽  
Yong-Da Sie ◽  
Tsung-Yun Liu ◽  
Hsiang-Ling Kuo ◽  
Pei-Yi Chou ◽  
...  

AbstractMetastatic cancer cells are frequently deficient in WWOX protein or express dysfunctional WWOX (designated WWOXd). Here, we determined that functional WWOX-expressing (WWOXf) cells migrate collectively and expel the individually migrating WWOXd cells. For return, WWOXd cells induces apoptosis of WWOXf cells from a remote distance. Survival of WWOXd from the cell-to-cell encounter is due to activation of the survival IκBα/ERK/WWOX signaling. Mechanistically, cell surface epitope WWOX286-299 (repl) in WWOXf repels the invading WWOXd to undergo retrograde migration. However, when epitope WWOX7-21 (gre) is exposed, WWOXf greets WWOXd to migrate forward for merge. WWOX binds membrane type II TGFβ receptor (TβRII), and TβRII IgG-pretreated WWOXf greet WWOXd to migrate forward and merge with each other. In contrast, TβRII IgG-pretreated WWOXd loses recognition by WWOXf, and WWOXf mediates apoptosis of WWOXd. The observatons suggest that normal cells can be activated to attack metastatic cancer cells. WWOXd cells are less efficient in generating Ca2+ influx and undergo non-apoptotic explosion in response to UV irradiation in room temperature. WWOXf cells exhibit bubbling cell death and Ca2+ influx effectively caused by UV or apoptotic stress. Together, membrane WWOX/TβRII complex is needed for cell-to-cell recognition, maintaining the efficacy of Ca2+ influx, and control of cell invasiveness.


1975 ◽  
Vol 19 (1) ◽  
pp. 11-20
Author(s):  
V.O. Sing ◽  
S. Bartnicki-Garcia

The binding of concanavalin A (Con A) to the cell surface of zoospores and cysts of Phytophthora palmivora was studied by radiometry (125I-Con A), ultraviolet microscopy (fluorescein-Con A) and electron microscopy peroxidase-diaminobenzidine technique). Zoospores were found to secrete during the early stages of encystment a Con A-binding material susceptible to trypsin digestion. This glycoprotein is contained in the so-called peripheral vesicles and is probably responsible for the adhesion of the encysting zoospores to solid surfaces.


2009 ◽  
Vol 187 (6) ◽  
pp. 831-845 ◽  
Author(s):  
George von Dassow ◽  
Koen J.C. Verbrugghe ◽  
Ann L. Miller ◽  
Jenny R. Sider ◽  
William M. Bement

Animal cells decide where to build the cytokinetic apparatus by sensing the position of the mitotic spindle. Reflecting a long-standing presumption that a furrow-inducing stimulus travels from spindle to cortex via microtubules, debate continues about which microtubules, and in what geometry, are essential for accurate cytokinesis. We used live imaging in urchin and frog embryos to evaluate the relationship between microtubule organization and cytokinetic furrow position. In normal cells, the cytokinetic apparatus forms in a region of lower cortical microtubule density. Remarkably, cells depleted of astral microtubules conduct accurate, complete cytokinesis. Conversely, in anucleate cells, asters alone can support furrow induction without a spindle, but only when sufficiently separated. Ablation of a single centrosome displaces furrows away from the remaining centrosome; ablation of both centrosomes causes broad, inefficient furrowing. We conclude that the asters confer accuracy and precision to a primary furrow-inducing signal that can reach the cell surface from the spindle without transport on microtubules.


2007 ◽  
Vol 546-549 ◽  
pp. 2097-2102
Author(s):  
Ting Luo ◽  
Yi Zhang ◽  
Qing Rong Feng

The relationship of the resistivity versus synthesizing temperature of sol-gel YBa2Cu3O7-x samples, with Tc 91K, was studied while synthesizing in flowing oxygen atmosphere. A set of high temperature -T curves were obtained for the whole process. After four rounds of synthesizing, the resistivity of the sample was =1.00×10-3cm at room temperature. The -T curve of the last round also showed that the orthorhombic to tetragonal phase transformation of the sample occurred around 600oC that is lower than the YBa2Cu3O7-x sample prepared in ambient atmosphere. Other measurements such as X-ray diffraction, SEM measurement, low temperature R-T and M-T measurement were also taken to get more information of these samples.


1974 ◽  
Vol 14 (1) ◽  
pp. 197-202
Author(s):  
M. INOUE

The binding of 131I-labelled concanavalin A (131I-Con A) to the cell surface has been studied in Ehrlich ascites tumour cells (EATC) and beef erythrocytes under various conditions. The binding of concanavalin A (Con A) to the cell surface was very specific and the available binding sites were saturated within a few minutes. The amount of 131I-Con A bound to EATC was 4.14 x 107 molecules/cell at 37 °C and 2.12 x 107 molecules/cell at 0 °C. Under these conditions, cell agglutination was observed only at 37 °C and not at 0 °C. However, the binding sites measured at 0 °C were also effective for agglutination at 37 °C. Beef erythrocytes were agglutinated by Con A only after treatment of cells with papain. The number of binding sites for Con A on the cell surface was decreased by this treatment to about half the number present on untreated cells. Various reagents such as colchicine, monoiodoacetic acid, dinitrophenol, rotenone, sodium azide and carboxyl cyanide-m-fluorophenylhydrazone (FCCP) had no effect on Con A-mediated cell agglutination. In contrast, periodate treatment produced a remarkable decrease in the agglutinability of cells. From these data, it is concluded that the cell agglutination induced by Con A was due to the topographical distribution of the surface receptors for the lectin, and not the result of energy-dependent or microtubule-dependent reaction processes. The number and the state of Con A receptors on the cell surface were in a dynamic condition, their conformation, orientation, and/or topographical distribution changing under different conditions.


2011 ◽  
Vol 189-193 ◽  
pp. 1184-1187 ◽  
Author(s):  
Jiu Xiao Sun ◽  
Yun Dong Ji ◽  
Yan Zi Yin ◽  
Ji Hui Wang

In this paper, effect of FBG coating in curing monitoring of composites was studied. In the experiment, three kinds of sensors were embedded in the composites. Excursion of the wavelength and temperature was tested in the whole curing process. 3-point bending test of composites which FBG was embedded in was done. Results showed that FBG could be exactly reflecting the relationship of stress and strain in bending state of composites. After cured, composites were heat up to 180°C for 1 hour. Sectional appearance of different optic fibers in room temperature and high temperature was got by optical microscope.


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