Effect of growth conditions on development of the cellular slime mould, Dictyostelium discoideum

Development ◽  
1972 ◽  
Vol 28 (2) ◽  
pp. 463-479
Author(s):  
D. R. Garrod ◽  
J. M. Ashworth
Keyword(s):  
Dictyostelium Discoideum ◽  
Fruiting Body ◽  
Physiological Mechanism ◽  
Growth Conditions ◽  
Fruiting Bodies ◽  
Body Proportions ◽  
Cellular Slime Mould ◽  
Slime Mould ◽  
Cellular Slime ◽  
The Difference

The effect of growth in the presence and absence of 86 mM glucose on fruiting-body number and size, fruiting-body proportions and morphogenesis in the slime mould Dictyostelium discoideum, strain Ax-2, has been investigated. Cells grown in the absence of glucose (n.s. cells) formed 2·1 times more fruiting bodies than glucose-grown cells allowed to differentiate under the same conditions and at the same cell density. Glucose fruiting bodies were 2·6 times larger than n.s. fruiting bodies. During aggregation, n.s. aggregation streams generally broke up into numerous secondary aggregation centres. Glucose streams generally did not break up but moved into the initial aggregation centre. Each secondary centre formed one small grex, whereas initial centres fragmented into several grexes which were larger than those formed from secondary centres. The preponderance of secondary centres in n.s. aggregation and of initial centres in glucose aggregation accounts for the difference in size and number of fruiting bodies. We speculate about the mechanism giving rise to the morphogenetic difference. The spore: stalk ratio was 3·95:1 in glucose fruiting bodies and 2·70:1 in n.s. fruiting bodies. This difference is not related to the difference in fruiting-body size because proportions are size invariant for both fruiting-body types. Some difference in the physiological mechanism which determines proportions is suspected.

The effect of chymotrypsin on the development of Dictyostelium discoideum

Development ◽  
1980 ◽  
Vol 57 (1) ◽  
pp. 189-201
Author(s):  
David C. Kilpatrick ◽  
Jerzy A. Schmidt ◽  
John L. Stirling ◽  
John Pacy ◽  
Gareth E. Jones
Keyword(s):  
Electron Microscopy ◽  
Dictyostelium Discoideum ◽  
Normal Development ◽  
Fruiting Bodies ◽  
Con A ◽  
Cellular Slime Mould ◽  
Slime Mould ◽  
Spore Walls ◽  
Cellular Slime ◽  
Vacuolated Cells

Development of the cellular slime mould Dictyostelium discoideum strain NC4, in the presence of α-chymotrypsin (3 mg/ml) is reversibly arrested at the tight aggregate stage (10/12 h). Pronase has a similar effect, but trypsin only retards normal development by about five hours. Normally developing cells are susceptible to α-chymotrypsin if they are transferred into its presence at any time up to the tight aggregate stage (10–12 h). Transfer after this stage does not affect the appearance of fruiting body structures in the normal time (24 h). Electron microscopy showed the ultrastructure of α-chymotrypsin-blocked aggregates after starvation for 24 h to be consistent with a block at 10–12 h of normal development. Poorly developed prespore vacuoles, having thin incomplete walls and a paucity of electrondense material, are present in some cells. No angular vacuolated cells characteristic of stalk cells are visible. Fruiting bodies formed in the presence of a α-chymotrypsin, either as minority structures when the enzyme is added before 10–12 h of normal development, or as the majority structures on later enzyme addition, were found to be abnormal. Normal stalks were formed but the spores were immature. Prespore vacuoles were present, though disrupted, and the cells were not encapsulated by spore walls. The electronegativity of intact slime mould amoebae was significantly reduced, and material containing L-[6-3H]-fucose and [l-14C]leucine was removed from the cell surface on α-chymotrypsin treatment. Few plasma membrane proteins were affected, however, and staining of polyacrylamide gels for glycopeptides using Con A-peroxide binding also showed little change.

Temperature-sensitive DNA repair mutations in the cellular slime mould Dictyostelium discoideum

1981 ◽  
Vol 3 (3) ◽  
pp. 167-171 ◽  
Author(s):  
Dennis L. Welker ◽  
Keith L. Williams
Keyword(s):  
Dna Repair ◽  
Dictyostelium Discoideum ◽  
Temperature Sensitive ◽  
Cellular Slime Mould ◽  
Slime Mould ◽  
Cellular Slime

Electrical properties of the slime mould grex

Development ◽  
1970 ◽  
Vol 23 (2) ◽  
pp. 311-322
Author(s):  
D. R. Garrod ◽  
J. F. Palmer ◽  
L. Wolpert
Keyword(s):  
Electrical Properties ◽  
Dictyostelium Discoideum ◽  
Fruiting Body ◽  
Fruiting Bodies ◽  
Electrophysiological Investigation ◽  
Slime Mould ◽  
Cellular Pattern ◽  
Electric Potentials

An electrophysiological investigation of the migrating grex of the slime mould, Dictyostelium discoideum, has been carried out with two aims in view. It was hoped to obtain information which would be relevant to, first, the formation and regulation of cellular pattern in the grex, and secondly, the problem of grex movement. During migration the grex develops a simple, linear cellular pattern. The cells at the front become the so-called ‘prestalk’ cells which will form the stalk of the fruiting body while those at the back become ‘prespore’ cells and form spores at culmination (Raper, 1940; Bonner, 1944; Bonner & Slifkin, 1949). Moreover, this cellular pattern is capable of polarized regulation. Raper (1940) has shown that portions isolated from the front or back of the grex are capable of forming normally proportioned fruiting bodies. A number of workers have suggested that bio-electric potentials may be involved in regulation of linear cellular pattern.

scholarly journals Growth of myxamoebae of the cellular slime mould Dictyostelium discoideum in axenic culture

1970 ◽  
Vol 119 (2) ◽  
pp. 171-174 ◽  
Author(s):  
D. J. Watts ◽  
J. M. Ashworth
Keyword(s):  
Cell Differentiation ◽  
Dictyostelium Discoideum ◽  
Axenic Culture ◽  
Axenic Medium ◽  
Cellular Slime Mould ◽  
Slime Mould ◽  
Solid Media ◽  
Cellular Slime

1. A simple axenic medium suitable for the growth of the myxamoebae of a strain of the cellular slime mould Dictyostelium discoideum is described. 2. Procedures suitable for the growth of this strain in liquid and on solid media are described. 3. Conditions suitable for initiating the cell differentiation of myxamoebae grown axenically are described.

Control of cellular differentiation by temperature in the cellular slime mould Dictyostelium discoideum

1984 ◽  
Vol 69 (1) ◽  
pp. 159-165
Author(s):  
M. Maeda
Keyword(s):  
Low Temperature ◽  
Dictyostelium Discoideum ◽  
Cellular Differentiation ◽  
Cellular Slime Mould ◽  
Slime Mould ◽  
Cellular Slime

The effects of low temperature on morphogenesis and cellular differentiation of Dictyostelium discoideum were examined. During incubation at 5 degrees C, the vegetative and preaggregation cells never developed, but cell masses at the aggregation or slug stage developed to form hemispherical, or dumbbell-shaped multicellular structures. By staining with FITC-antispore IgG, the structures formed after 10 days of incubation of tipped aggregates at 5 degrees C were found to be composed of 90% spores, 5% prespore cells and 5% non-stained cells. Since only 20% of the total cells constituting the tipped aggregate had been prespore cells at the beginning of incubation, this showed that spore differentiation proceeded even at low temperature, while stalk differentiation was completely inhibited. Similar results were obtained when the cells were incubated at 3 degrees C. However, at 0 degree C, morphogenesis and cellular differentiation did not occur, although most of the prespore cells at the late culmination stage differentiated incompletely into spores. Possible reasons for the high proportion of spores being induced by low temperature are discussed.

Sign in / Sign up

Export Citation Format

Share Document