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.

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 signal from fruiting body and conus tips of Dictyostelium discoideum

Development ◽  
1976 ◽  
Vol 36 (2) ◽  
pp. 261-271
Author(s):  
Jonathan Rubin
Keyword(s):  
Dictyostelium Discoideum ◽  
Fruiting Body ◽  
Beef Heart ◽  
Fruiting Bodies

Tips from fruiting bodies and conuses were transplanted into interphase fields of Dictyostelium discoideum amoebae. Progressively increasing concentrations of beef-heart phosphodiesterase added to the fields significantly decreased the chemotactic range of the responding amoebae. The findings suggest that the tip secretes c-AMP. We also find that the chemotactic range is independent of the size of the tip implying that the tip may produce a regulating gradient.

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.

A components study of competition in two cellular slime mold species: Dictyostelium discoideum and Polysphondylium pallidum

1971 ◽  
Vol 49 (8) ◽  
pp. 1163-1177 ◽  
Author(s):  
Donald J. McQueen
Keyword(s):  
Dictyostelium Discoideum ◽  
Computer Model ◽  
Fruiting Body ◽  
Slime Mold ◽  
Mixed Cultures ◽  
Cellular Slime Mold ◽  
Fruiting Bodies ◽  
Polysphondylium Pallidum ◽  
Cellular Slime ◽  
Time Required

The mechanics of a short-term interspecific competitive situation for two species of cellular slime mold, Dictyostelium discoideum and Polysphondylium pallidum, were assessed experimentally, modelled mathematically, and linked together to form a computer model, the predictions of which were tested. Five major components in the model were exploitation, toxic interference, effect of physical factors or external forces, availability of resources, and number of potential competitors engaged in exploitation and interference. The exploitation component depended upon time required for spore germination, rate and form of amoeba colony expansion, time required for fruiting body production, and rate and form of fruiting body colony expansion.Both species interfered with the other's ability to form fruiting bodies. In mixed cultures, D. discoideum amoebae divided and consumed food between 9° and 27 °C but did not produce fruiting bodies above 24 °C. In mixed cultures, P. pallidum amoebae divided and consumed food between 18° and 37 °C but did not produce fruiting bodies below 24 °C. Temperature altered the parameter values of all subcomponents contributing to exploitation and interference. Numbers altered interference ability. A computer model for predicting area occupied by fruiting bodies of both species was used to run 324 simulations and was accurate in 90.1% of the cases.

Cooperation induces other cooperation: Fruiting bodies promote the evolution of macrocysts in Dictyostelium discoideum

2017 ◽  
Vol 421 ◽  
pp. 136-145 ◽  
Author(s):  
Shota Shibasaki ◽  
Yuka Shirokawa ◽  
Masakazu Shimada
Keyword(s):  
Dictyostelium Discoideum ◽  
Fruiting Bodies

scholarly journals A Putative Ariadne-Like Ubiquitin Ligase Is Required for Dictyostelium discoideum Development

2006 ◽  
Vol 5 (10) ◽  
pp. 1820-1825 ◽  
Author(s):  
Nathaniel Whitney ◽  
Lacey J. Pearson ◽  
Ryan Lunsford ◽  
Lisa McGill ◽  
Richard H. Gomer ◽  
...  
Keyword(s):  
Dictyostelium Discoideum ◽  
Ubiquitin Ligase ◽  
Fruiting Bodies ◽  
Wild Type ◽  
Cell Numbers

ABSTRACT The Dictyostelium rbrA gene encodes a putative Ariadne ubiquitin ligase. rbrA − cells form defective slugs that cannot phototax. Prestalk cell numbers are reduced in rbrA − slugs, and these prestalk cells do not localize to the tip of slugs. Chimeric slugs containing wild-type cells could phototax and form fruiting bodies.

Cell movement within aggregates of the slime mould Dictyostelium discoideum revealed by surface markers

Development ◽  
1965 ◽  
Vol 13 (1) ◽  
pp. 97-117
Author(s):  
B. M. Shaffer
Keyword(s):  
Dictyostelium Discoideum ◽  
Cell Movement ◽  
Surface Markers ◽  
Slime Mould ◽  
Culture Plate ◽  
Multicellular Organisms

Earlier workers examined the behaviour of foreign particles placed as markers on aggregates of D. discoideum that were migrating over the surface of the culture plate (Bonner, 1959; Francis, 1959, 1962). Comparable observations, made on aggregates in other conditions and at other stages, have now provided further information about the movement of individual cells within the aggregates. Before reporting them, the course of development must be described in some detail. During aggregation on an ordinary culture plate, D. discoideum amoebae crawl towards centres, in which they pack themselves together, forming rounded aggregates of no fixed shape. Papillae develop on the side of the aggregates away from the agar, and by extension, roughly perpendicular to the substratum, transform them into cylindrical multicellular organisms with tapered tips (Text-fig. 1, A—E). Such an organism, which contains from a dozen to a few hundred thousand cells, has been named a grex (Shaffer, 1962) because ‘aggregation’ is derived from the Latin aggregare, to form a grex.

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.

scholarly journals Lessons on fruiting body morphogenesis from genomes and transcriptomes of Agaricomycetes

2021 ◽  
Author(s):  
Laszlo G Nagy ◽  
Peter Jan Vonk ◽  
Markus Kunzler ◽  
Csenge Foldi ◽  
Mate Viragh ◽  
...  
Keyword(s):  
Cell Wall ◽  
Fruiting Body ◽  
Expression Patterns ◽  
Schizophyllum Commune ◽  
Gene Families ◽  
Second Phase ◽  
Fruiting Bodies ◽  
Body Development ◽  
Fruiting Body Development

Fruiting bodies of mushroom-forming fungi (Agaricomycetes) are among the most complex structures produced by fungi. Unlike vegetative hyphae, fruiting bodies grow determinately and follow a genetically encoded developmental program that orchestrates tissue differentiation, growth and sexual sporulation. In spite of more than a century of research, our understanding of the molecular details of fruiting body morphogenesis is limited and a general synthesis on the genetics of this complex process is lacking. In this paper, we aim to comprehensively identify conserved genes related to fruiting body morphogenesis and distill novel functional hypotheses for functionally poorly characterized genes. As a result of this analysis, we report 921 conserved developmentally expressed gene families, only a few dozens of which have previously been reported in fruiting body development. Based on literature data, conserved expression patterns and functional annotations, we provide informed hypotheses on the potential role of these gene families in fruiting body development, yielding the most complete description of molecular processes in fruiting body morphogenesis to date. We discuss genes related to the initiation of fruiting, differentiation, growth, cell surface and cell wall, defense, transcriptional regulation as well as signal transduction. Based on these data we derive a general model of fruiting body development, which includes an early, proliferative phase that is mostly concerned with laying out the mushroom body plan (via cell division and differentiation), and a second phase of growth via cell expansion as well as meiotic events and sporulation. Altogether, our discussions cover 1480 genes of Coprinopsis cinerea, and their orthologs in Agaricus bisporus, Cyclocybe aegerita, Armillaria ostoyae, Auriculariopsis ampla, Laccaria bicolor, Lentinula edodes, Lentinus tigrinus, Mycena kentingensis, Phanerochaete chrysosporium, Pleurotus ostreatus, and Schizophyllum commune, providing functional hypotheses for ~10% of genes in the genomes of these species. Although experimental evidence for the role of these genes will need to be established in the future, our data provide a roadmap for guiding functional analyses of fruiting related genes in the Agaricomycetes. We anticipate that the gene compendium presented here, combined with developments in functional genomics approaches will contribute to uncovering the genetic bases of one of the most spectacular multicellular developmental processes in fungi. Key words: functional annotation; comparative genomics; cell wall remodeling; development; fruiting body morphogenesis; mushroom; transcriptome

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