Memoirs: The Cytology of Amoeba Proteus ‘Y’ and the Effects of Large and Small Centrifugal Forces

1938 ◽  
Vol s2-80 (320) ◽  
pp. 601-634
Author(s):  
B. N. SINGH

1. When Amoeba proteus is subjected to high centrifugal force most of the cytoplasmic bodies are thrown out of the cell, so this work was done with the ordinary electrical centrifuge. 2. The stratification of the various cytoplasmic components according to their specific gravity is as follows: the contractile vacuole and the fat, being the lightest, occupy the centripetal position; then there is a layer of cytoplasm followed by mitochondria, neutral-red bodies, crystals, and nutritive spheres. The nucleus occupies a position in between the crystals and the nutritive spheres (Text-fig. 2). 3. The redistribution of the various cytoplasmic components takes place within a few minutes after amoebae have been centrifuged by the electrical centrifuge. Ultra-centrifuged organisms kept in culture solution remain rounded for 10-15 days, and no cyst formation takes place. The crystals and nutritive spheres are reformed; the former seem to be the products of excretion formed by the metabolic activity of the cell. 4. The nutritive spheres contain glycogen as reserve food material, and give positive tests for glycogen with iodine and Best's carmine. 5. There is no evidence that the bodies which stain with neutral red are the homologue of the metazoan Golgi apparatus, although they are pre-existing bodies in Amoeba proteus . The contractile vacuole does not blacken even after prolonged osmication. No certain homologue of the Golgi apparatus was found in Amoeba proteus. 6. Fat and glycogen are two distinct types of storage material present in Amoeba proteus. The former is very well seen with osmic acid, Sudan IV, and Nile blue tests.

1938 ◽  
Vol s2-80 (320) ◽  
pp. 567-591
Author(s):  
J. BRONTË GATENBY ◽  
B. N. SINGH

1. In Copromonas subtilis , Dobell, and Euglena sp. there is a Golgi apparatus consisting of osmiophil material in the form of granules, which are associated with the osmoregulatory mechanism of the cell. 2. Inside the granules, water collects, so that they become spherical vacuoles, identical with what have in the past been called contractile vacuoles (Copromonas) or accessory contractile vacuoles (Euglena viridis). 3. In Euglena viridis, the Golgi apparatus is closely applied to the so-called contractile vacuole, and consists of numerous loaf-shaped osmiophil bodies which undergo a regular series of changes from systole to diastole, and vice versa. 4. In Copromonas, the osmiophil material may form a thick cortex surrounding what has been called the reservoir, it may be attached to the reservoir in fairly regular loafshaped bodies as in Euglena, or it may be completely detached from the reservoir. 5. The so-called contractile vacuoles of Copromonas are vesicles containing water, which are formed on the site of the osmiophil granules. 6. As far as we are able to say at present, the reservoir of Copromonas is indistinguishable from an enlarged contractile vacuole, and new reservoirs probably arise from swollen contractile vacuoles. It is difficult to believe that the reservoir divides into two, as has been claimed by Dobell. 7. During division of Copromonas, two reservoirs can nearly always be found in the early stages before the nucleus becomes dumb-bell shaped. These seem to have originated from the osmiophil vacuoles. 8. The remaining osmiophil material, when present, moves slightly down the cell, occupying a place in the mid-line. When the new cell-wall between the two organisms has passed down, about one-third the length of the dividing monad, the osmiophil material splits into two sub-equal groups and is so divided between the two organisms. There is therefore a definite dictyokinesis to be found in Copromonas. 9. Just at or after this period, the osmiophil material may become scattered about the upper middle and upper region of the dividing monads, but finally becomes situated in the region of the reservoir. 10. The osmiophil material (Golgi apparatus) persists throughout conjugation and encystment, even when a reservoir cannot be found. 11. There is a rhizoplast joining the basal granule of the flagellum with the intra-nuclear nucleolo-centrosome, and an axostyle is present, passing from the basal granule to the posterior end of the organism. 12. During cell division, the basal granule divides into two and appears to lose its connexion with the two nucleolo-centrosomes of the dividing nucleus. The axostyle appears to be absorbed in the early stages of division and cannot be stained at this epoch, but reappears in each moiety of the dividing organism, when the nucleus is dumb-bell shaped. It appears to reform when the two basal granules have taken their definitive position at the anterior end of the cells. 13. We agree with Wenyon that one flagellum passes over intact to one of the daughter cells at division, the other flagellum arises from the other basal granule. 14. Numerous fat granules are found throughout the organism; what have been called volutin granules in other Protozoa are present in Copromonas, and stain in neutral red. 15. Mitochondria are present mainly in the posterior region of the organism.


1940 ◽  
Vol s2-81 (324) ◽  
pp. 595-617
Author(s):  
J. BRONTÉ GATENBY ◽  
J. D. SMYTH

1. In Chilomonas paramecium the contractile vacuole is surrounded by a cortical substance (Golgi apparatus) which has the power of reducing osmium tetroxide solution and thus impregnating black (Nassonow). 2. This cortex blackens thus in over 99 per cent, of individuals in a culture which has not been dividing. In a culture in which the individuals have been rapidly dividing, the percentage of unimpregnated contractile vacnoles increases considerably, up to about 5 per cent. 3. During division of Chilomonas in about 70 per cent. of cases the osmiophile substance is very equally divided between the daughter cells. The dividing cortex comes away from the contractile vacuole, which eventually collapses, new contractile vacuoles arising in the site of the divided osmiophile material. In about 25 per cent, of division stages osmication of the cortex fails to a greater or lesser degree. There is always a very distinct tendency for this failure to take place even in the best of preparations. 4. In some cases (about 3 per cent.), during division, the entire contractile vacuole and its cortex goes over whole to one individual. A new vaeuole, apparently without cortex, arises spontaneously in the other individual. It is unlikely that all of these cases are due to failure of impregnation in one of the individuals, though this possibility cannot be roled out completely. 5. The behaviour of the original contractile vacuole cavity before separation of the daughter cells is as follows. The lipoid, having partially retreated from the vacuole, becomes separated into two parts, and the centrally placed vacuole disappears (figs. 4 and 6, Pl. 36; figs. 10 and 15, Pl. 37). New vacuoles appear in the site of the lipoid bodies in each daughter cell (fig. 5, Pl. 36). 6. Two ellipsoidal accessory bodies or pyrenoids lie on a level with the vestibule. In older cultures the two bodies are often exactly the same size and colour (corrosive osmic followed by neutral red or haematoxylin), but in rapidly dividing cultures, one body may be of normal size, whereas the other may be absent or much smaller. During cell division, one body is carried across to each daughter. No exception to this was ever found. 7. Identification of the smaller Peranemidae is in a confused state. Probably several species, and possibly even genera, have been described by various authors as Scytomonas (Copromonas) subtilis.


1930 ◽  
Vol s2-73 (291) ◽  
pp. 477-506
Author(s):  
VISHWA NATH

1. Observations on the living ovary. The earthworm ovary, as also that of the medicinal leech, is surprisingly favourable material for the study of the Golgi apparatus and the mitochondria in the living condition. The Golgi elements stand out very prominently in all stages of oogenesis as highly refractile spherules of a dark-greyish colour, performing a dancing movement in the cell. In the earliest oogonia situated near the septal insertion of the ovary there is a single Golgi spherule lying near the nuclear membrane. It probably divides at first into two and then into four, till in advanced oocytes there is a large number of Golgi elements distributed uniformly in the cytoplasm. The mitochondria in the earliest oogonia cannot be detected. Soon, however, they arise in the form of either a horseshoe closely fitting the nuclear membrane or a roundish mass, consisting of whitish granules, much less refractile than the Golgi elements. Gradually they spread out in the cytoplasm and perform a dancing movement. The Golgi elements and the mitochondria remain unaltered for a long time after the death of the cell. Attention is drawn to the excellent work of Foot and Strobell (1901), who described in the fresh egg of Allolobophora only two types of granules, namely, the ‘deutoplasmic’ or ‘osmiophile’ granules (Golgi elements) and the ‘archoplasmic’ or ‘yolk-nucleus’ granules (mitochondria). They have also shown only one osmiophile granule in their photographs of the earliest oogonia. 2. Observations on the living stained ovary. Neutral red and janus green B do not in any way improve the visibility of the inclusions, if indeed any improvement were desired. The Golgi elements do not at all stain with neutral red. The mitochondria may appear slightly blue with janus green. 3. Observations on fresh ovaries treated with osmic acid. The importance of this technique is greatly emphasized. After five to ten minutes' osmication the Golgi elements become copper-coloured, but they still appear solid. After half an hour's osmication they become slightly black and each element now shows very clearly a dark peripheral rim and a clear central area. The element is therefore not a solid or a semi-solid body, but a vesicle with a definite osmiophilic rim and a hollow interior. After two hours' osmication the vesicles become still blacker. 4. Experiments with the Centrifuge. The centrifuge very clearly reveals the existence of only two types of inclusions, namely, the Golgi elements and the mitochondria. There is neither yolk nor any other type of inclusion. 5. Observations on Fixed Preparations. If a Champy-fixed ovary is mounted whole, the Golgi elements appear as black granules. Within a month or so, however, they are decolorized by xylol. This proves the existence of fat inside the Golgi vesicle. In Champy-fixed sections, however, the vesicles are decolorized immediately after immersion in xylol. Kolatschev preparations demonstrate very satisfactorily the vesicular shape of the Golgi element. 6. The morphology of the Golgi apparatus in general is discussed in detail in the light of the recent work of Gatenby, Hirschler, Bowen, and others.


1936 ◽  
Vol s2-78 (311) ◽  
pp. 513-531
Author(s):  
J. A. MULIYIL

1. Recent researches have established that the Y-granules exist as a fundamental part of the constitution of the male germ-cells of many animals, vertebrates as well as invertebrates. 2. Prior to the application of vital staining techniques to cytological problems, Saccocirrus was the only animal in which these granules were known to exist. 3. The fixatives generally used by cytologists, especially those containing acetic acid and other fat solvents, are not indicated for studying the Y-granules. Vital staining techniques offer the best method for their study. 4. Underfeeding and starvation of the larvae of Agrotis segetum and Abraxas grossulariata revealed that these granules are products of normal metabolic activity, and that their appearance and disappearance depend on the general physiological status of the animal. 5. In normally fed larvae the Y-granules were invariably present, and responded to the vital dye within a few minutes of its application. The germ-cells of underfed larvae showed a steady decrease in their Y-granule contents, as did starved larvae up to a certain stage. When starvation was prolonged the granules disappeared from the cell. 6. The changes produced by underfeeding and starvation in the cell, both in the Y-granule content and the colloidal state of the cytoplasm, were decidedly more pronounced in the spermatocytes than in the spermatids. In very advanced stages of the cell scarcely any change was perceptible. 7. The chemical composition of the granules was determined by studying their reactions to certain vital dyes and fixatives. Neutral red, brilliant Cresyl blue, and Nile-blue sulphate were successfully used to stain the granules, Nile-blue sulphate being particularly satisfactory. This stain is specific for fats and substances chemically allied to fats. 8. Y-granules are composed of either fatty acids or a mixture of fatty acids and neutral fat, because they always stain blue with Nile-blue sulphate. 9. Fixatives containing osmic acid failed to stain the granules except in rare cases when they appeared brown in the preparations. As a rule they appeared a shade of pale grey. As this is a reaction for saturated fatty acids it is believed that in the majority of cases where in fixed preparations the granules are seldom visible, they are composed of saturated fatty acids. 10. The fatty nature of the material was confirmed by fixing testis smears in formalin vapour, and staining them with Herxheimer's solution of acetone and scarlet B. If the preparations are counterstained in methylene blue the Y-granules are clearly seen stained pink--a reaction indicating the fatty acid nature of the granules. 11. An examination of the ovaries of Abraxas grossul ariata, Gryllus domesticus, and Lithobius forficatus, supra vitally stained in neutral red, revealed in everycase a juxtanuclear aggregate of neutral red staining granules. With the growth of the oocytes the granules wandered into the cytoplasm and gradually developed into small spheres; their substance simultaneously underwent a chemical change. By the aid of Nile-blue sulphate it was possible to ascertain that the fatty acid contents of the granules gradually changed into fat, or rather into fatty yolk. 12. The behaviour of the granules in the oocytes suggest that the Y-granules in the spermatocytes are only abortive yolk granules having no function under normal conditions. But a gradual reduction in their number, observed in several spermatocytes when the animals were starved, suggests that under exceptional circumstances there is a possibility of the granules exercising some sort of storage function.


1963 ◽  
Vol s3-104 (68) ◽  
pp. 445-458
Author(s):  
JENNIFER M. BYRNE

The effect of keeping Amoeba proteus in dilute basic dye solutions was studied. It was found that Nile blue, neutral red, and neutral violet in particular, and also brilliant cresyl blue, methylene blue, Bismarck brown, thionin, toluidine blue, and azures A and B act as vital dyes, while at comparable molarities crystal violet, dahlia, safranin, methyl green, Janus green, and Victoria blue are lethal, and do not produce any staining until after death. Azure C, basic fuchsin, and particularly pyronine G are relatively harmless, but produce no vital staining. All the vital dyes stain the food vacuoles, and all produce small, darkly stained granules in colourless vacuoles in the cytoplasm. The latter do not exist in the unstained amoeba. Some of the dyes colour vacuoles around the crystals. These crystal vacuoles also seem to be induced. A few of the dyes colour the spherical refractive bodies, which are at least in part phospholipid. All the basic dyes used with the possible exception of azure C, methyl green, and pyronine G attach to the external membrane of A. proteus in an orientated manner, as shown by the increase in birefringence of the external membrane induced by these dyes. It is particularly those dyes that act as vital dyes that produce a very pronounced increase in the birefringence of the external membrane.


The formation of mucus in goblet cells and its relation to the Golgi apparatus has been studied by various workers. Nassanow (1923) showed clearly that the mucin granules in the goblet cells of Triton originated in the Golgi apparatus, and so brought secretion in these cells into line with his theory of the bound secretion. More recently Clara (1926) has shown in the goblet cells of birds that the mucin first appears in the region next to the nucleus, between it and the gland lumen. Florey (1932, a, b ) has considered this more extensively in two recent papers, and for a number of mammals has shown that the mucin granules of goblet cells first form in the meshes of the Golgi network. In epithelial cells of the mouse vagina, undergoing conversion into mucous cells, he has found that the same process occurs. In a recent investigation of secretory formation in the salivary glands and pancreas it was found by the present author that in every cell type examined the young secretory granules first appeared in the basal region of the cell in relation to the mitochondria. Subsequent emigration occurred into the Golgi zone, where they underwent conversion into mature secretory granules. In the mucous cells of the salivary glands it was shown that these newly formed granules might be stained intravitam by Janus green or neutral red, and that in fixed preparations they stained selectively with acid fuchsin as described by Noll (1902), In the light of this work it appeared probable that while mucin formation might occur in the Golgi zone of the goblet cells as described by these authors, the origin of the granules might lie in the basal region of the cell.


2004 ◽  
Vol 29 (4) ◽  
pp. 85-90 ◽  
Author(s):  
Eri Nishihara ◽  
Teruo Shimmen ◽  
Seiji Sonobe

2008 ◽  
Vol 100 (3) ◽  
pp. 179-188 ◽  
Author(s):  
Eri Nishihara ◽  
Etsuo Yokota ◽  
Akira Tazaki ◽  
Hidefumi Orii ◽  
Maki Katsuhara ◽  
...  

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