The Golgi complex of the early spermatid in guinea pig

1986 ◽  
Vol 216 (2) ◽  
pp. 139-145 ◽  
Author(s):  
M. H. Burgos ◽  
L. S. Gutiérrez
Author(s):  
J. J. Geuze ◽  
J. W. Slot

The precise localization of secretory proteins in exocrine pancreatic cells has not yet been elucidated. Especially the role of the Golgi complex in protein processing remains a matter of controversy. Based on morphological and autoradiographical work with the frog pancreas, we described proteins moving from the peripheral elements at the cis (immature) side of the Golgi complex across the stack of Golgi cisternae towards the condensing vacuoles at the trans (mature) side of the Golgi complex. Jamieson and Palade described a similar pathway in the stimulated Guinae pig pancreas, but suggested that in unstimulated cells the Golgi cisternae are bypassed and that vesicles carry proteins directly from the RER to the condensing vacuoles. Novikoff et al. postulate from their study on pancreatic cells of 4 mammalian species including Guinea pig and rat that condensing vacuoles can originate directly from specialized regions of the ER (so-called GERL) at the trans side of the Golgi complex. This makes the role of the peripheral elements and the Golgi cisternae in protein processing even more doubtful.


1971 ◽  
Vol 50 (2) ◽  
pp. 498-515 ◽  
Author(s):  
Barbara A. Nichols ◽  
Dorothy Ford Bainton ◽  
Marilyn G. Farquhar

The origin, content, and fate of azurophil granules of blood monocytes were investigated in several species (rabbit, guinea pig, human) by electron microscopy and cytochemistry. The life cycle of monocytes consists of maturation in bone marrow, transit in blood, and migration into tissues where they function as macrophages. Cells were examined from all three phases. It was found that: azurophil granules originate in the Golgi complex of the developing monocyte of bone marrow and blood, and ultimately fuse with phagosomes during phagocytosis upon arrival of monocytes in the tissues. They contain lysosomal enzymes in all species studied and peroxidase in the guinea pig and human. These enzymes are produced by the same pathway as other secretory products (i.e., they are segregated in the rough ER and packaged into granules in the Golgi complex). The findings demonstrate that the azurophil granules of monocytes are primary lysosomes or storage granules comparable to the azurophils of polymorphonuclear leukocytes and the specific granules of eosinophils. Macrophages from peritoneal exudates (72–96 hr after endotoxin injection) contain large quantities of lysosomal enzymes throughout the secretory apparatus (rough ER and Golgi complex), in digestive vacuoles, and in numerous coated vesicles; however, they lack forming or mature azurophil granules. Hence it appears that the monocyte produces two types of primary lysosomes during different phases of its life cycle—azurophil granules made by developing monocytes in bone marrow or blood, and coated vesicles made by macrophages in tissues and body cavities.


1960 ◽  
Vol 8 (3) ◽  
pp. 761-775 ◽  
Author(s):  
Hilton H. Mollenhauer ◽  
William Zebrun

Observations on the fine structure of KMnO4-fixed testes of small mammals (guinea pig, rat, and mouse) reveal certain morphological differences between the spermatogenic and Sertoli cells which have not been demonstrated in the same tissue fixed with OsO4. Aggregates of minute circular profiles, much smaller than the spherical Golgi vesicles, are described in close association with the Golgi complex of developing spermatids. Groups of dense flattened vesicles, individually surrounded by a membrane of different dimensions than that which bounds most of the other cell organelles, appear dispersed within the cytoplasm of some spermatogenic cells. Flattened vesicles of greater density than those belonging to the Golgi complex are reported confined to the inner Golgi zone of developing guinea pig spermatids between the Golgi cisternae and the head cap. The profiles of endoplasmic reticulum within spermatocytes appear shorter, wider, and more tortuous than those of Sertoli cells. Minute cytoplasmic particles approximately 300 A in diameter and of high electron opacity appear randomly disposed in some Sertoli cells. Groups of irregular-shaped ovoid bodies within the developing spermatids are described as resembling portions of cytoplasm from closely adjacent spermatids. Interpretation is presented regarding the fine structure of KMnO4-fixed testes in view of what has already been reported for mammalian testes fixed in OsO4.


1968 ◽  
Vol 3 (1) ◽  
pp. 95-104
Author(s):  
MURIEL WALKER ◽  
H. C. MACGREGOR

The testis of Nucella consists of numerous tubules, all directed inwards and joining to form a common testicular duct. In a single tubule the spermatogonia lie round the periphery. Mature sperm line the lumen of the tubule. Cells in the same stage of spermatogenesis are grouped together and all members of a group pass through spermatogenesis in phase. Staining with fast green before and after treatment with Van Slyke reagent indicates a change from lysine-rich to arginine-rich histone in the maturing spermatid. Sperm of Nucella are motile throughout their length. The sperm are thread-like and about 80 µ long. The head is Feulgen-positive and about 40 µ long. The mid-piece lies behind the head and is about 8 µ long. The flagellum runs from the front end of the head to the tip of the tail; in the head it is completely surrounded by the nucleus. The spermatogonia contain two centrioles situated near the nucleus and a conspicuous Golgi complex. There are synaptinemal complexes in spermatocyte nuclei in the synapsis stage. In the early spermatid the centriole pushes a tube through the nucleus. This tube is lined by nuclear membrane and is occupied by the anterior portion of the flagellar shaft. The nucleus elongates and the nucleoprotein condenses into strands arranged helically along the long axis of the nucleus. These strands fuse to form lamellae, which disappear in the mature sperm. Mitochondria aggregate at the base of the early spermatid nucleus and form a loose spiral around the flagellar shaft. The outer mitochondrial membranes fuse. The mid-piece of the mature sperm consists of a large tubular mitochondrion enclosing a portion of the flagellar shaft. At the early spermatid stage a pro-acrosomal granule is formed from a large Golgi complex. From this the acrosome develops; it consists of a cone and an acrosome granule. There are two sets of microtubules associated with the acrosome, one lying within the cone, the other outside the cone and separated from it by a ‘ragged membrane’. The microtubules of the outer set extend backwards along the head for two-thirds of its length. The centriole which gives rise to the flagellar shaft lies at the anterior end of the head and is separated from the acrosome by a thin layer of nucleoprotein and a double layer of nuclear envelope. There is no second centriole or derivative thereof in the mature sperm. In the tail groups of coiled fibres are associated with each pair of the peripheral flagellar fibrils.


1967 ◽  
Vol 34 (2) ◽  
pp. 577-596 ◽  
Author(s):  
James D. Jamieson ◽  
George E. Palade

It has been established by electron microscopic radioautography of guinea pig pancreatic exocrine cells (Caro and Palade, 1964) that secretory proteins are transported from the elements of the rough-surfaced endoplasmic reticulum (ER) to condensing vacuoles of the Golgi complex possibly via small vesicles located in the periphery of the complex. To define more clearly the role of these vesicles in the intracellular transport of secretory proteins, we have investigated the secretory cycle of the guinea pig pancreas by cell fractionation procedures applied to pancreatic slices incubated in vitro. Such slices remain viable for 3 hr and incur minimal structural damage in this time. Their secretory proteins can be labeled with radioactive amino acids in short, well defined pulses which, followed by cell fractionation, makes possible a kinetic analysis of transport. To determine the kinetics of transport, we pulse-labeled sets of slices for 3 min with leucine-14C and incubated them for further +7, +17, and +57 min in chase medium. At each time, smooth microsomes ( = peripheral elements of the Golgi complex) and rough microsomes ( = elements of the rough ER) were isolated from the slices by density gradient centrifugation of the total microsomal fraction. Labeled proteins appeared initially (end of pulse) in the rough microsomes and were subsequently transferred during incubation in chase medium to the smooth microsomes, reaching a maximal concentration in this fraction after +7 min chase incubation. Later, labeled proteins left the smooth microsomes to appear in the zymogen granule fraction. These data provide direct evidence that secretory proteins are transported from the cisternae of the rough ER to condensing vacuoles via the small vesicles of the Golgi complex.


1978 ◽  
Vol 79 (1) ◽  
pp. 45-58 ◽  
Author(s):  
L G Paavola

This study characterizes the cytochemical properties of the Golgi complex, the structure which corresponds to Golgi complex-endoplasmic reticulum-lysosomes (GERL), and the granule population in luteal cells of guinea pigs at the time of maximum progesterone secretion, in material fixed by vascular perfusion, a method particularly suited for preserving both fine structure and enzyme activity. The distribution of several marker enzymes was determined by electron microscope cytochemistry. Acid phosphatase (ACPase) and arylsulfatase were used to identify structures containing lysosomal proteins. To resolve specific problems, additional cytochemical markers were employed: localization of thiamine pyrophosphatase (TPPase) (in the Golgi complex) and alkaline phosphatase (ALPase) (a plasma membrane marker), and prolonged osmication (a generally accepted method of marking the outer cisterna of the Golgi complex). The results demonstrate that at the time of peak steroid secretion the Golgi complex in luteal cells, in marked contrast to that of most other cell types, typically displays intense ACPase activity in all of its cisternae. Similarly, all Golgi cisternae stain after prolonged osmication and may show TPPase activity. On the other hand, GERL in luteal cells of this age, unlike that in most cells, commonly shows low levels of, or lacks, ACPase activity. However, GERL resembles that of other cell types in being TPPase-negative and in being unstained by treatment with aqueous OsO4. GERL and some Golgi cisternae are reactive for ALPase. The granule population in luteal cells of this stage consists of lysosomes, multivesicular bodies, electrontransparent vacuoles, and microperoxisome-like bodies. These results form a base line with which luteolytic changes described in the companion study (Paavola, L.G. 1978. The corpus luteum of the guinea pig. III. Cytochemical studies on the Golgi complex and GERL during normal postpartum regression of luteal cells, emphasizing the origin of lysosomes and autophagic vacuoles. J. Cell. Biol. 79:59--73.) can be compared.


1961 ◽  
Vol 10 (1) ◽  
pp. 37-45 ◽  
Author(s):  
Lucien G. Caro

Electron microscopic radioautographs of guinea pig pancreatic exocrine cells were obtained by covering thin sections (∼ 600 A) of OsO4-fixed, methacrylate-embedded tissue with thin layers of Ilford K-5 nuclear research emulsion. After an exposure of 13 days at 4°C., the preparations were photographically processed, stained with uranyl acetate, and examined in an electron microscope. The label used was leucine-H3 injected intravenously 20 minutes before collection of the specimens. Conventional radioautographs of thicker sections (0.4 micron) were also examined in a phase contrast microscope. The advantages obtained from electron microscopic radioautography are: the higher radioautographic resolution (of the order of 0.3 micron) due to the thinness of the emulsion and the specimen, and a high optical resolution permitting a clear identification of the labeled structure. In the guinea pig pancreas this technique demonstrated that, at the time studied, newly synthesized proteins were concentrated in the structures of the Golgi complex and especially in large vacuoles partially filled with a dense material. The vacuoles are probably a precursor to the secretion granules (zymogen granules) in which the label becomes segregated at a later time. These observations demonstrate directly the role of the Golgi complex in the secretion process. They also illustrate the possibilities of this method for radioautography at the intracellular level.


1978 ◽  
Vol 79 (1) ◽  
pp. 59-73 ◽  
Author(s):  
L G Paavola

The postpartum involution of corpora lutea was examined by electron microscope cytochemistry of guinea pig ovaries previously fixed by vascular perfusion, a method which produces optimal preservation of steroid-secreting cells and yet maintains enzyme activity. The intracellular digestive apparatus was identified through the localization of two acid hydrolases, acid phosphatase (ACPase) and arylsulfatase. Other marker enzymes localized were thiamine pyrophosphatase (in Golgi cisternae) and alkaline phosphatase (along plasma membranes). Prolonged osmication was used to mark the outer Golgi cisterna. The results demonstrate that luteal cell regression is characterized by a striking increase in the number of lysosomes and the appearance of numerous, double-walled autophagic vacuoles. Both lysosomes and the space between the double walls of autophagic vacuoles exhibit ACPase and arylsulfatase activity. In contrast to earlier periods, just before and during regression, Golgi complex-endoplasmic reticulum-lysosomes (GERL) is markedly hypertrophied, displaying intense acid hydrolase activity. On the basis of various criteria, GERL is proposed to function in the formation of lysosomes and autophagic vacuoles. Lysosomes seem to develop from GERL as focal protuberances of varying size and shape, which detach from the parent structure. Double-walled autophagic vacuoles, often large and complex in structure, initially are produced as GERL cisternae envelop small areas of cytoplasm. Lytic enzymes, perhaps furnished by the engulfing membranes and trapped lysosomes, presumably bring about digestion of the contents of these vacuoles, producing first aggregate-type inclusions, then, as the contents are further degraded, myelin figure-filled residual bodies. ACPase activity occasionally appears within smooth endoplasmic reticulum tubules and cisternae in advanced regression, possibly suggesting that lytic enzymes utilize this membrane system as an access route to GERL. These data indicate that cellular autophagy is a prominent mechanism underlying luteal cell involution during normal postpartum degeneration of guinea pig corpora lutea. Furthermore they suggest that in regressing luteal cells GERL is responsible for packaging acid hydrolases into lytic bodies.


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