Redistribution of material labelled with [3H]mannose in amoebae induced to undergo pinocytosis

1982 ◽  
Vol 58 (1) ◽  
pp. 79-93
Author(s):  
C.J. Flickinger
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Cell Surface ◽  
Rough Endoplasmic Reticulum ◽  
Lysosomal Enzymes ◽  
Surface Material ◽  
Albumin Solution ◽  
Electron Microscopic ◽  
Normal Medium ◽  
Electron Microscopic Radioautography

The synthesis, transport, and disposition of material labelled with [3H]mannose were studied by electron microscopic radioautography in normal amoebae and in cells that had internalized cell surface as a result of being induced to undergo pinocytosis. Control amoebae were injected with the precursor and placed in normal medium. The Golgi apparatus and rough endoplasmic reticulum were heavily labelled at the earliest intervals, while radioactivity of the cell surface peaked 12 h after injection of precursor. The experimental cells were injected, placed in bovine serum albumin solution from 15 to 60 min after injection, and then removed to normal medium until fixation. Incorporation of the precursor into the rough endoplasmic reticulum was near normal, but the proportions of grains associated with the Golgi apparatus and the cell surface were greatly reduced. The percentage of grains overlying vacuoles increased 12 h after injection, notably in the case of polymorphous vacuoles and dense vacuoles, both of which were identified as lysosomes with the acid phosphatase reaction. The results suggest that addition to the surface of components labelled with [3H]mannose was diminished following induction of pinocytosis. Incorporation of the precursor appeared to be shifted from cell surface material to lysosomal contents, possibly lysosomal enzymes. It is thought that this shift occurred in response to the need for the cell to digest unusually large amounts of endocytosed protein. Recycling of cell surface under these conditions is considered possible.

scholarly journals IN VIVO INCORPORATION OF 3H-GALACTOSE BY THYROID FOLLICULAR CELLS OF THE RAT, AS SHOWN BY ELECTRON MICROSCOPIC RADIOAUTOGRAPHY

1972 ◽  
Vol 20 (3) ◽  
pp. 220-224 ◽  
Author(s):  
A. HADDAD
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Rough Endoplasmic Reticulum ◽  
Side Chains ◽  
Follicular Cells ◽  
Electron Microscopic ◽  
Thyroid Follicular Cells ◽  
Apical Vesicles ◽  
Electron Microscopic Radioautography

Radioactive galactose was injected intravenously into rats and localized in thyroid follicular cells by electron microscopic radioautography at intervals ranging from 2.5 to 30 min after injection. The galactose label was mostly present in the Golgi apparatus at 2.5 min, with some of it in the adjacent rough endoplasmic reticulum. By 30 min, the label was found in apical vesicles and colloid. It was concluded that galactose is added to the carbohydrate side chains of incomplete thyroglobulin molecules during their travel through the cisternae of the endoplasmic reticulum into the Golgi apparatus; the uptake begins as this organelle is approached, but predominates within it. The thyroglobulin molecule which has thus been labeled is transported by the apical vesicles to the colloid.

Altered labelling of the cell surface and intracellular organelles with [3H]mannose in enucleated amoebae

1984 ◽  
Vol 68 (1) ◽  
pp. 83-94
Author(s):  
C.J. Flickinger
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Cell Surface ◽  
Rough Endoplasmic Reticulum ◽  
Intracellular Transport ◽  
Cell Organelles ◽  
Intracellular Organelles ◽  
And Control ◽  
Kinetics Of ◽  
Heavy Labelling

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.

scholarly journals The amounts and rates of export of polysaccharides found within the membrane system of maize root cells

1974 ◽  
Vol 142 (1) ◽  
pp. 139-144 ◽  
Author(s):  
Dianna J. Bowles ◽  
D. H. Northcote
Keyword(s):  
Endoplasmic Reticulum ◽  
Cell Wall ◽  
Golgi Apparatus ◽  
Cell Surface ◽  
Rough Endoplasmic Reticulum ◽  
Membrane System ◽  
Maize Root ◽  
Wall Material ◽  
Cell Wall Material ◽  
Root Cells

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.

scholarly journals ELECTRON MICROSCOPIC RADIOAUTOGRAPHIC DETECTION OF SITES OF PROTEIN SYNTHESIS AND MIGRATION IN LIVER

1969 ◽  
Vol 43 (2) ◽  
pp. 237-249 ◽  
Author(s):  
Charles A. Ashley ◽  
Theodore Peters
Keyword(s):  
Endoplasmic Reticulum ◽  
Protein Synthesis ◽  
Rough Endoplasmic Reticulum ◽  
Plasma Proteins ◽  
Liver Slice ◽  
Cell Periphery ◽  
Electron Microscopic ◽  
Golgi Bodies ◽  
And Migration ◽  
Electron Microscopic Radioautography

The sites of synthesis of proteins and their subsequent migration in rat liver have been studied during a 75 min period after labeling of liver-slice proteins by exposure to leucine-H3 for 2 min. Incorporation of the label into protein began after 1 min and was maximal by 4 min. Electron microscopic radioautography showed that synthesis of proteins in hepatocytes occurs mainly on ribosomes, particularly those in rough endoplasmic reticulum and, to some extent, in nuclei and mitochondria. Most of the newly formed proteins leave the endoplasmic reticulum in the course of 40 min, and concurrently labeled proteins appear in Golgi bodies, smooth membranes, microbodies, and lysosomes. A likely pathway for the secretion of some or all plasma proteins is from typical rough endoplasmic reticulum to a zone of reticulum which is partially coated with ribosomes, to the Golgi apparatus, and thence to the cell periphery. The formation of protein by reticuloendothelial cells was measured and found to be about 5% of the total protein formed by the liver.

Changes of organelles associated with the differentiation of epidermal melanocytes in the mouse

Development ◽  
1978 ◽  
Vol 43 (1) ◽  
pp. 107-121
Author(s):  
Tomohisa Hirobe ◽  
Takuji Takeuchi
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Rough Endoplasmic Reticulum ◽  
Smooth Endoplasmic Reticulum ◽  
Mouse Skin ◽  
Newborn Mouse ◽  
Electron Microscopic ◽  
Induced Differentiation ◽  
Newborn Mice ◽  
Old Mice

Electron microscopic observations on normally differentiating and α-MSH (melanocytestimulating hormone)-treated epidermal melanocytes of newborn mouse skin were carried out. The process of melanocyte differentiation from premelanosome-containing melanoblasts was investigated in detail with respect to melanosomes as markers. Melanoblasts containing unmelanized premelanosomes gradually decreased in number after birth, while the number of melanocytes rapidly increased. The epidermis of α-MSH-treated 3-day-old mice and normal 6-day-old mice contained melanocytes with numerous fully melanized melanosomes, and with no or only a few melanoblasts. Changes in other organelles in differentiating melanocytes were also noticeable. Golgi apparatus and RER (rough endoplasmic reticulum) decreased in number during the normal or α-MSH-induced differentiation of the epidermal melanocytes, though the number of mitochondria showed no notable change. The number of SER (smooth endoplasmic reticulum) per cell did not change in the cells of newborn mice, while in α-MSH-treated cells the number increased significantly. These results led us to an assumption that Golgi apparatus or RER transforms into other forms of organelles including melanosomes and SER during the differentiation of melanocytes.

Spermatogenesis in the Dragonfly with Particular Reference to the Cytoplasmic Organelles

1972 ◽  
Vol 30 ◽  
pp. 110-111
Author(s):  
Sant S. Sekhon
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Mature Sperm ◽  
Electron Microscopic ◽  
Cytoplasmic Organelles ◽  
Microscopic Studies ◽  
Insect Sperm ◽  
Large Round

Although there have been numerous studies concerning the morphogenetic changes accompanying the maturation of insect sperm, only a few deal with the sperm differentiation in the dragonflies. In two recent electron microscopic studies Kessel, has comprehensively treated the erlationship of microtubules to the nucleus and mid-piece structures during spermiogenesis in the dragonfly. The purpose of this study is to follow the sequential nuclear and cytoplasmic changes which accompany the differentiation of spermatogonium into a mature sperm during spermatogenesis in the dragonfly (Aeschna sp.).The dragonfly spermatogonia are characterized by large round nuclei. Loosely organized chromatin is usually unevenly distributed within the spermatogonial nuclei. The scant cytoplasm surrounding the nucleus contains mitochondria, the Golgi apparatus, elements of endoplasmic reticulum and numerous ribosomes (Fig. 1).

scholarly journals Immunocytochemical localization of Mullerian inhibiting substance in the rough endoplasmic reticulum and Golgi apparatus in Sertoli cells of the neonatal calf testis using a monoclonal antibody.

1984 ◽  
Vol 32 (6) ◽  
pp. 649-654 ◽  
Author(s):  
M Hayashi ◽  
H Shima ◽  
K Hayashi ◽  
R L Trelstad ◽  
P K Donahoe
Keyword(s):  
Monoclonal Antibody ◽  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Rough Endoplasmic Reticulum ◽  
Sertoli Cells ◽  
Neonatal Calf ◽  
Müllerian Inhibiting Substance ◽  
Pap Method ◽  
Unlabeled Antibody ◽  
Mullerian Inhibiting Substance

Mullerian Inhibiting Substance (MIS) has been localized in the Sertoli cells of the neonatal calf testis using preembedding immunoperoxidase techniques and a monoclonal antibody which almost completely blocks the biological activity of MIS. Both the peroxidase-labeled antibody method using a peroxidase-conjugated F(ab')2 fragment of IgG as a second antibody and the unlabeled antibody peroxidase-antiperoxidase (PAP) method using Fab fragments of the PAP complex were employed. With both methods, MIS was demonstrated within the cisternae of the rough endoplasmic reticulum (RER) and the Golgi apparatus. In the Golgi, MIS was concentrated in the transmost cisternae especially at their peripheral expansions. This study indicates that MIS is synthesized in the RER and transported to the Golgi apparatus, presumably for glycosidation, before secretion from Golgi derived vacuoles.

scholarly journals The pattern of appearance of enzymic activity during the development of the Golgi apparatus in amoebae

1978 ◽  
Vol 34 (1) ◽  
pp. 53-63
Author(s):  
C.J. Flickinger
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Rough Endoplasmic Reticulum ◽  
Enzymic Activity ◽  
Nuclear Transplantation ◽  
Similar Distribution ◽  
Cytochemical Staining ◽  
Light Reaction ◽  
Golgi Bodies ◽  
Golgi Membranes

The appearance of enzymic activity during the development of the Golgi apparatus was studied by cytochemical staining of renucleated amoebae. In cells enucleated for 4 days, there was a great decline in size and number of Golgi bodies, or dictyosomes. Subsequent renucleation by nuclear transplantation resulted in a regeneration of Golgi bodies. Samples of amoebae were fixed and incubated for cytochemical staining at intervals of 1, 6, or 24 h after renucleation. Enzymes selected for study were guanosine diphosphatase (GDPase), esterase, and thiamine pyrophosphatase (TPPase). All three were found in the Golgi apparatus of normal amoebae but they differed in their overall intracellular distribution. GDPase was normally present at the convex pole of the Golgi apparatus, in rough endoplasmic reticulum, and in the nuclear envelope. In amoebae renucleated for 1 h, light reaction product for GDPase was present throughout the small stacks of cisternae that represented the forming Golgi apparatus. By 6 h following the operation GDPase reaction product was concentrated at the convex pole of the Golgi apparatus. Esterase, which was distributed throughout the stacks of normal Golgi cisternae, displayed a similar distribution in the forming Golgi bodies as soon as they were visible. TPPase was normally present in the Golgi apparatus but was not found in the endoplasmic reticulum. In contrast to the other enzymes, TPPase reaction product was absent from the forming Golgi apparatus 1 and 6 h after renucleation, and did not appear in the Golgi apparatus until 24 h after operation. Thus, enzymes held in common between the rough endoplasmic reticulum and the Golgi apparatus were present in the forming Golgi apparatus as soon as it was detectable, but an enzyme cytochemically localized to the Golgi apparatus only appeared later in development of the organelle. It is suggested that Golgi membranes might be derived from the endoplasmic reticulum and thus immediately contain endoplasmic reticulum enzymes, while Golgi-specific enzymes are added later in development.

Sign in / Sign up

Export Citation Format

Share Document