Function of coated membranes and multivesicular bodies during membrane regulation in stimulated exocrine pancreas cells

Geuze, J. J.; Kramer, M. F.

doi:10.1007/bf00220098

Cited by 69 publications

(19 citation statements)

References 33 publications

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“…Cell corpses from these cells were made by electric perforation of the cellular membranes so that most of the soluble cytoplasmic proteins were allowed to leak through (Gorden and Seglen 1986). Rat pancreas was obtained from secretion-stimulated rats (Geuze and Kramer 1974). ML1, an EBV-transformed human B-cell line, was provided by Dr.…”

Section: Methodsmentioning

confidence: 99%

Improving structural integrity of cryosections for immunogold labeling

Liou

Geuze

Slot

1996

Histochem Cell Biol

489

335

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Cryosections of aldehyde-fixed material prepared according to Tokuyasu are a good substrate for immunocytochemistry. However, structural defects occur that limit the resolution of this approach. We found that the step during which sections are thawed and transferred from the cryochamber to the supporting film on an EM grid is most critical for structural preservation. Surface tension of the transfer medium, on which sections are spread during thawing, can easily damage their structure by overstretching. By substituting a mixture of methylcellulose and sucrose for the conventional sucrose transfer medium, we were able to alleviate the problem of overstretching, thus improving greatly the structural integrity of thin cryosections. Also, material extraction from the sections after thawing causes structural damage, particularly when cross-linking is deficient. Incorporation of uranyl acetate in the transfer medium can then further help to maintain the structural integrity of the sections during the immunolabeling procedure. Excellent ultrastructure was featured in sections picked up and dried directly in methylcellulose/uranyl acetate mixtures. Such preparations can provide new insight into subcellular details and is an efficient back-up for immunolabeled sections in respect of their morphology. Cryosections from fresh frozen tissue can be preserved for immunolabeling by using transfer media that contain fixatives. This approach may have advantages if chemical fixation of tissue is thought to induce morphological artifacts or antigen redistribution.

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Section: Methodsmentioning

confidence: 99%

Improving structural integrity of cryosections for immunogold labeling

Liou

Geuze

Slot

1996

Histochem Cell Biol

489

335

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“…Previously, cytochemical tracers such as hor eradish peroxidase or particulate tracers such as ferritin or deitran have been used to study membrane retrieval in a variety of cells (4)(5)(6)(7)(8)(9)(10)(21)(22)(23)(24)(25)(26)(27)(28). In all cases uptake of tracer by endocytosis has been noted, but only in anterior pituitary cells and neurons (11) has the marker been traced to the Golgi complex t where it was usually found to be limited to a single cisterna located along the trans-side of the Golgi stacks (9,10 earlier results, our new findings demonstrate a considerably more extensive labeling which involves practically all cisternae of the Golgi stacks.…”

Section: Resultsmentioning

confidence: 99%

“…Previous morphological studies using various electron-opaque tracers clearly indicate that some membrane is retrieved by endocytosis in secretory cells. However, there has been no agreement concerning the distribution of the retrieved membrane that has been variously claimed to fuse with lysosomes (4)(5)(6)(7), GERL (8), and the innermost (trans) Golgi cisterna (9)(10)(11).…”

mentioning

confidence: 99%

Luminal membrane retrieved after exocytosis reaches most Golgi cisternae in secretory cells

Herzog

Farquhar

1977

Proc. Natl. Acad. Sci. U.S.A.

192

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Dextran was used to trace membrane retrieved from the luminal surface after induced exocytosis in secretory cells of rat lacrimal and parotid glands. Two different approaches were used: (a) isolated acini were incubated in vitro with dextran followed by stimulation with carbamylcholine (lacrimal) or isoproterenol (parotid) and (b) rats were injected with isoproterenol followed by dextran infusion into the parotid duct in vivo. The main findings were the same regardless of the gland source or experimental approach. Dextran was taken up initially via coated pits into smooth-surfaced apical vesicles. Shortly thereafter it was found in multiple cell compartments: within the stacked Golgi cisternae, in condensing vacuoles, and in lysosomes. Uptake was more rapid and uniform in vivo; dextran was seen in multiple cisternae of numerous Golgi complexes within 5 min after infusion. In acini incubated in vitro uptake into Golgi cisternae was more delayed and occurred with increasing frequency up to 60 min; also, more dextran was taken up into Iysosomes, which were more numerous in vitro than in vivo. The results demonstrate that, after exocytosis, membrane is removed from the cell surface via vesicles that fuse with multiple cell compartments. The two novel findings are: (a) the demonstration that the tracer can reach most of the Golgi cisternae in a given stack and (b) the demonstration of the rapidity with which the process takes place (i.e., within 5 min). The findings imply that at least some membrane retrieved from the cell surface after exocytosis fuses with the stacked Golgi cisternae. Release of macromolecular secretory products from glandular cells occurs primarily, if not exclusively, by exocytosis. During this process the limiting membranes of secretion granules are inserted into the plasmalemma. This implies that a comparable amount of membrane must be removed from the cell surface since under normal conditions the distribution of membranes among participating compartments, including the plasmalemma, remains constant (1). Little is known concerning the nature or fate of the membrane removed from the surface of glandular cells. Available biochemical data indicate that in acinar cells of the pancreas (2) and of the parotid gland (3), the proteins of granule membranes are synthesized at a much slower rate than secretory proteins, suggesting that granule membrane components may be recovered and used for packaging of successive waves of secretion granules (1-3). Previous morphological studies using various electron-opaque tracers clearly indicate that some membrane is retrieved by endocytosis in secretory cells. However, there has been no agreement concerning the distribution of the retrieved membrane that has been variously claimed to fuse with lysosomes (4-7), GERL (8), and the innermost (trans) Golgi cisterna (9-11).In this study we have used dextran to trace the route taken by internalized plasma membrane in acinar cells of rat lacrimal and parotid glands after stimulation of exocytosis, and we Prepara...

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“…Geuze et al [1977] point out that the coated, budding areas seen in the pancreatic acinar cell condensing vacuoles possibly will form coated microvesicles, representing zones of membrane elimination. The flask shaped connection between the coated vesi cles and the condensing vacuole as noted b\ Geuze and Kramer' [1974] suggests that the coated vesicles are 'pinching-off from the condensing vacuole rather than merging with it. The bulging coated areas ('fusionpinching off' images) we observed in the type II condensing vacuoles ( fig.…”

Section: Decrease In Condensing Vacuole Sizementioning

confidence: 99%

Freeze-fracture and thin-section study of condensing vacuoles in rat pancreatic acinar cells

Sesso

Assis

Kuwajima

et al. 1980

Cells Tissues Organs

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Early and late developmental forms of condensing vacuoles are prominent in the relatively low rate secreting acinar cells of suckling rat pancreas. These vacuoles, when studied in freeze-fracture replicas and ultrathin sections under standard processing conditions, showed a biphasic evolution. During the first stage the condensing vacuoles (referred to as CVj) enlarge, accumulating contents of rather low electron density. Fracture faces with irregular patterns, possibly the result of fusion (pinching off) of microvesicles with (from) the condensing vacuoles, were occasionally encountered. The infrequency of such images indicates that fusion-fission during the growth stage must be a very rapid event. One common type of surface irregularity is gibbosities (or convexities) in the P fracture face with complementary images in the E fracture face. The significance of these irregularities, which are in apparent discordance with the theory of microvesicular transport, is unclear. By the end of the growing period the condensing vacuoles are large and smooth-surfaced (referred to as CV₂) with contents of intermediate electron density (between that of the initial growing stage and that of the mature zymogen granule). The number of intercalated particles on both the large irregularly surfacec CV_1·) and large smooth-surfaced condensing vacuoles (CV₂) membranes is high and comparable to that of the Golgi saccule and endoplasmic reticulum membranes. During the second stage, the smooth-surfaced condensing vacuoles undergo volume reduction associated with progressive increase in the electron density of their contents, thus becoming zymogen granules. Concomitant with size reduction, the number of intercalated particles in the membranes with CV₂ diminishes markedly. The process of membrane retrieval appears to be accomplished selectively by pinching off coated microvesicles heavily studded with intercalated particles.

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Function of coated membranes and multivesicular bodies during membrane regulation in stimulated exocrine pancreas cells

Cited by 69 publications

References 33 publications

Improving structural integrity of cryosections for immunogold labeling

Improving structural integrity of cryosections for immunogold labeling

Luminal membrane retrieved after exocytosis reaches most Golgi cisternae in secretory cells

Freeze-fracture and thin-section study of condensing vacuoles in rat pancreatic acinar cells

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