scholarly journals Immunocytochemical demonstration of intracytoplasmic alkaline phosphatase in HeLa TCRC-1 cells.

1981 ◽  
Vol 29 (9) ◽  
pp. 1080-1087 ◽  
Author(s):  
S Tokumitsu ◽  
K Tokumitsu ◽  
W H Fishman

The ultrastructural localization of alkaline phosphatase has been examined in cells of a HeLa subline (TCRC-1) that are monophenotypic for Regan isoenzyme expression. Enzyme activity was demonstrated at the cell surface plasma membrane and in certain lysosomes as revealed by the lead citrate method. The regular direct immunoperoxidase procedure utilizing antibodies in IgG or Fab' form showed the same distribution patterns of alkaline phosphatase. However, when the cell surface antigen was blocked in advance with specific unlabeled antibodies and direct immunocytochemistry performed in the presence of saponin, intracellular alkaline phosphatase antigen was observed in the perinuclear space, endoplasmic reticulum, and Golgi apparatus. The results appeared to be concordant with the current concept that membrane glycoproteins are formed in the endoplasmic reticulum, modified in the Golgi apparatus and then transported to the cell surface. Intracellular alkaline phosphatase was observed predominantly in some cell populations especially mitotic cells, suggesting that the enzyme protein was synthesized in and around the mitotic phase. Accordingly, this technique of differential membrane immunocytochemistry appears to provide an opportunity to follow ectopic gene expression as a function of cell cycle and enzyme induction.

1980 ◽  
Vol 87 (3) ◽  
pp. 783-791 ◽  
Author(s):  
L Kaariainen ◽  
K Hashimoto ◽  
J Saraste ◽  
I Virtanen ◽  
K Penttinen

Temperature-sensitive mutants of semliki forest virus (SFV) and sindbis virus (SIN) were used to study the intracellular transport of virus membrane glycoproteins in infected chicken embryo fibroblasts. When antisera against purified glycoproteins and (125)I- labeled protein A from staphylococcus aureus were used only small amounts of virus glycoproteins were detected at the surface of SFV ts-1 and SIN Ts-10 infected cells incubated at the restrictive temperature (39 degrees C). When the mutant-infected cells were shifted to the permissive temperature (28 degrees C), in the presence of cycloheximide, increasing amounts of virus glycoproteins appeared at the cell surface from 20 to 80 min after the shift. Both monensin (10muM) and carbonylcyanide-p- trifluoromethoxyphenylhydrazone (FCCP; 10-20 muM) inhibited the appearance of virus membrane glycoproteins at the cell surface. Vinblastine sulfate (10 μg/ml) inhibited the transport by approximately 50 percent, whereas cytochalasin B (1 μg/ml) had only a marginal effect. Intracellular distribution of virus glycoproteins in the mutant-infected cells was visualized in double-fluorescence studies using lectins as markers for endoplasmic reticulum and Golgi apparatus. At 39 degrees C, the virus membrane glycoproteins were located at the endoplasmic reticulum, whereas after shift to 28 degrees C, a bright juxtanuclear reticular fluorescence was seen in the location of the Golgi apparatus. In the presence of monensin, the virus glycoproteins could migrate to the Golgi apparatus, although transport to the cell surface did not take place. When the shift was carried out in the presence of FCCP, negligible fluorescence was seen in the Golgi apparatus and the glycoproteins apparently remained in the rough endoplasmic reticulum. A rapid inhibition in the accumulation of virus glycoproteins at the cell surface was obtained when FCCP was added during the active transport period, whereas with monensin there was a delay of approximately 10 min. These results suggest a similar intracellular pathway in the maturation of both plasma membrane and secretory glycoproteins.


1984 ◽  
Vol 68 (1) ◽  
pp. 83-94
Author(s):  
C.J. Flickinger

The production, transport, and disposition of material labelled with [3H]mannose were studied in microsurgically enucleated and control amoebae. Cells were injected with the precursor and samples were prepared for electron-microscope radioautography at intervals, up to 24 h later. Control cells showed heavy labelling of the rough endoplasmic reticulum and the Golgi apparatus at early intervals after injection. Later, labelling of groups of small vesicles increased, and the percentage of grains over the cell surface peaked 12 h after administration of the precursor. Two major changes were detected in enucleate amoebae. First, the kinetics of labelling of cell organelles with [3H]mannose were altered in the absence of the nucleus. The Golgi apparatus and cell surface both displayed maximal labelling at later intervals in enucleates, and the percentage of grains over the rough endoplasmic reticulum varied less with time in enucleated than in control cells. Second, the distribution of radioactivity was altered. A greater percentage of grains was associated with lysosomes in enucleates than in control cells. The change in the kinetics of labelling of the endoplasmic reticulum, Golgi apparatus and cell surface indicates that intracellular transport of surface material was slower in the absence of the nucleus. It is suggested that this is related to the decreased motility of enucleate cells.


Blood ◽  
1982 ◽  
Vol 59 (6) ◽  
pp. 1132-1140 ◽  
Author(s):  
MF Gourdin ◽  
JP Farcet ◽  
F Reyes

Abstract The cellular distribution of immunoglobulins in human malignant and normal B cells was investigated by immunoelectron microscopy by direct incubation of fixed cells with electron microscopy by direct incubation of fixed cells with peroxidase-coupled antibody. These conjugates penetrated into the cell, resulting in the simultaneous detection of surface and cytoplasmic immunoglobulins. The latter were seen as specific intracisternal staining of the perinuclear space and endoplasmic reticulum and occasionally of the Golgi complex. Plasma cells were frequently characterized by a heterogeneity of reactivity of the endoplasmic reticulum. Minute amounts of cytoplasmic immunoglobulin were demonstrated in cells without developed secretory organelles, such as lymphoma cells and lymphocytes from chronic lymphocytic leukemia (CLL). The method allowed us to define several subsets of cells according to the expression of surface and cytoplasmic immunoglobulins and thus to determine the stage of maturation of cells involved in monoclonal proliferation.


2000 ◽  
Vol 148 (1) ◽  
pp. 17-28 ◽  
Author(s):  
Thomas Machleidt ◽  
Wei-Ping Li ◽  
Pingsheng Liu ◽  
Richard G.W. Anderson

Caveolin-1 is an integral membrane protein of caveolae that is thought to play an important role in both the traffic of cholesterol to caveolae and modulating the activity of multiple signaling molecules at this site. The molecule is synthesized in the endoplasmic reticulum, transported to the cell surface, and undergoes a poorly understood recycling itinerary. We have used mutagenesis to determine the parts of the molecule that control traffic of caveolin-1 from its site of synthesis to the cell surface. We identified four regions of the molecule that appear to influence caveolin-1 traffic. A region between amino acids 66 and 70, which is in the most conserved region of the molecule, is necessary for exit from the endoplasmic reticulum. The region between amino acids 71 and 80 controls incorporation of caveolin-1 oligomers into detergent-resistant regions of the Golgi apparatus. Amino acids 91–100 and 134–154 both control oligomerization and exit from the Golgi apparatus. Removal of other portions of the molecule has no effect on targeting of newly synthesized caveolin-1 to caveolae. The results suggest that movement of caveolin-1 among various endomembrane compartments is controlled at multiple steps.


1984 ◽  
Vol 99 (6) ◽  
pp. 2011-2023 ◽  
Author(s):  
J W Wills ◽  
R V Srinivas ◽  
E Hunter

The envelope glycoproteins of Rous sarcoma virus (RSV), gp85 and gp37, are anchored in the membrane by a 27-amino acid, hydrophobic domain that lies adjacent to a 22-amino acid, cytoplasmic domain at the carboxy terminus of gp37. We have altered these cytoplasmic and transmembrane domains by introducing deletion mutations into the molecularly cloned sequences of a proviral env gene. The effects of the mutations on the transport and subcellular localization of the Rous sarcoma virus glycoproteins were examined in monkey (CV-1) cells using an SV40 expression vector. We found, on the one hand, that replacement of the nonconserved region of the cytoplasmic domain with a longer, unrelated sequence of amino acids (mutant C1) did not alter the rate of transport to the Golgi apparatus nor the appearance of the glycoprotein on the cell surface. Larger deletions, extending into the conserved region of the cytoplasmic domain (mutant C2), resulted in a slower rate of transport to the Golgi apparatus, but did not prevent transport to the cell surface. On the other hand, removal of the entire cytoplasmic and transmembrane domains (mutant C3) did block transport and therefore did not result in secretion of the truncated protein. Our results demonstrate that the C3 polypeptide was not transported to the Golgi apparatus, although it apparently remained in a soluble, nonanchored form in the lumen of the rough endoplasmic reticulum; therefore, it appears that this mutant protein lacks a functional sorting signal. Surprisingly, subcellular localization by internal immunofluorescence revealed that the C3 protein (unlike the wild type) did not accumulate on the nuclear membrane but rather in vesicles distributed throughout the cytoplasm. This observation suggests that the wild-type glycoproteins (and perhaps other membrane-bound or secreted proteins) are specifically transported to the nuclear membrane after their biosynthesis elsewhere in the rough endoplasmic reticulum.


1974 ◽  
Vol 142 (1) ◽  
pp. 139-144 ◽  
Author(s):  
Dianna J. Bowles ◽  
D. H. Northcote

1. Maize seedling roots were incubated in vivo with d-[U-14C]glucose for 2, 5, 10, 15, 30 and 45min. The total incorporation of radioactivity into polysaccharide components in isolated fractions was investigated, and the pattern of incorporation into different polysaccharide components within the rough endoplasmic reticulum, Golgi apparatus and exported material was analysed. 2. The membrane compartments reached a saturation value of radioactivity in polysaccharide components by 30min incubation. Radioactivity in exported polysaccharide continued to increase after that time. The latter was formed and maintained by a steady-state turnover of polysaccharide synthesis and transport from the membrane system. 3. If the only access of the slime polysaccharide to the cell surface is via dictyosome-derived vesicles, the amount of slime components in the Golgi apparatus would have to be displaced every 0.3min in order to maintain the observed rates of increase in slime. This is in contrast with a displacement time of about 2.5min that is necessary for polysaccharide components in the Golgi apparatus to produce the observed increase in cell-wall material. The activity of the membrane system in the production of maize root slime is 8 times as great as that of the membrane system involved in cell-wall synthesis. 4. If the amount of polysaccharide material in the Golgi apparatus is maintained only by inflow of polymeric material from the rough endoplasmic reticulum the total amount of slime components in the rough endoplasmic reticulum would have to be displaced every 7min to maintain a constant amount in the Golgi apparatus. If the endoplasmic reticulum contributed directly to the cell surface in the synthesis of cell-wall material, displacement times necessary to maintain the observed rate of polymer production would be very slow.


Blood ◽  
1982 ◽  
Vol 59 (6) ◽  
pp. 1132-1140
Author(s):  
MF Gourdin ◽  
JP Farcet ◽  
F Reyes

The cellular distribution of immunoglobulins in human malignant and normal B cells was investigated by immunoelectron microscopy by direct incubation of fixed cells with electron microscopy by direct incubation of fixed cells with peroxidase-coupled antibody. These conjugates penetrated into the cell, resulting in the simultaneous detection of surface and cytoplasmic immunoglobulins. The latter were seen as specific intracisternal staining of the perinuclear space and endoplasmic reticulum and occasionally of the Golgi complex. Plasma cells were frequently characterized by a heterogeneity of reactivity of the endoplasmic reticulum. Minute amounts of cytoplasmic immunoglobulin were demonstrated in cells without developed secretory organelles, such as lymphoma cells and lymphocytes from chronic lymphocytic leukemia (CLL). The method allowed us to define several subsets of cells according to the expression of surface and cytoplasmic immunoglobulins and thus to determine the stage of maturation of cells involved in monoclonal proliferation.


1970 ◽  
Vol 6 (3) ◽  
pp. 701-719
Author(s):  
G. F. LEEDALE ◽  
B. S. C. LEADBEATER ◽  
A. MASSALSKI

Cells of the chrysophycean flagellate Olisthodiscus luteus contain bundles of aligned tubes and fibres within membrane-limited vesicles. Each element in a vesicle consists of a tapering portion 0.25µm long, a shaft 1.5µm long and a terminal fibre 0.25µm long; the shaft is approximately 15nm in diameter and has a helical cross-banding with a periodicity of 8nm. The flagellar hairs of Olisthodiscus have identical morphology and dimensions to these internal elements. Zoospores of the filamentous xanthophycean algae Bumilleria sicula, Heterococcus spp. and Tribonema spp. have similar internal vesicles containing aligned tubes and fibres with precisely the same morphology and dimensions as the flagellar hairs: base plus shaft, 1-2µm long, two terminal fibres per hair, 0.5-0.8µm long, shaft diameter of approximately 15nm and a helical periodicity of the shaft of 8nm. The aligned tubes are absent from the vegetative xanthophycean cell, appear during zoosporogenesis and disappear during early stages of zoospore settlement. It is suggested that the aligned tubes and fibres are potential flagellar hairs which are formed in the perinuclear space (and possibly other regions of the endoplasmic reticulum) and are then transported to the cell surface in vesicles of the ER for deposition on the flagella. A review of information available on the Chrysophyceae, Xanthophyceae, Phaeophyceae and Bacillariophyceae indicates that internal formation of flagellar hairs is probably the rule in the heterokont algal groups, and a similar process apparently occurs in at least the dinoflagellates, the cryptomonads and some aquatic fungi among other groups of organisms with hairy flagella.


Sign in / Sign up

Export Citation Format

Share Document