Cyclic AMP-induced changes in protein synthesis in a cellular slime mould, Polysphondylium pallidum

Nature ◽  
1975 ◽  
Vol 258 (5537) ◽  
pp. 763-765 ◽  
Author(s):  
DAVID FRANCIS
Keyword(s):  
Protein Synthesis ◽  
Cyclic Amp ◽  
Cellular Slime Mould ◽  
Slime Mould ◽  
Polysphondylium Pallidum ◽  
Cellular Slime ◽  
Induced Changes

Spots and stripes: the patterning spectrum in the cellular slime mould Polysphondylium pallidum

Development ◽  
1989 ◽  
Vol 105 (2) ◽  
pp. 323-333
Author(s):  
J.G. McNally ◽  
E.C. Cox
Keyword(s):  
Pattern Formation ◽  
Specific Antigen ◽  
Spherical Cell ◽  
The Novel ◽  
Cellular Slime Mould ◽  
Slime Mould ◽  
Size And Shape ◽  
Polysphondylium Pallidum ◽  
Cellular Slime ◽  
Pattern Determination

Whorls of the cellular slime mould Polysphondylium pallidum originate as spherical cell masses that during normal morphogenesis produce tips only at equidistant positions around their equator. We have observed a series of new patterns in whorls that differ from normal whorls only in that they are larger or more elongated. Among the novel patterns found were arrays of tips distributed fairly regularly over the whole whorl surface, as well as striped patterns detected at earlier stages with a tip-specific antigen. These altered patterns demonstrate that a whorl's size and shape are by themselves important factors in pattern determination. We have compared the range of observed patterns to those predicted by a variety of different theories. We find that while no one theory can account in detail for all of our observations, predictions based on Turing's scheme of pattern formation come the closest.

RNA and protein synthetic patterns during germination of Polysphondylium pallidum microcysts

1978 ◽  
Vol 24 (4) ◽  
pp. 480-486 ◽  
Author(s):  
David I. Gwynne ◽  
Danton H. O'Day
Keyword(s):  
Molecular Weight ◽  
Protein Synthesis ◽  
Amino Acid ◽  
Rna Synthesis ◽  
Leucine Incorporation ◽  
Small Molecular Weight ◽  
Cellular Slime Mould ◽  
Low Level ◽  
Polysphondylium Pallidum ◽  
Cellular Slime

During microcyst germination in the cellular slime mould Polysphondylium pallidum, an immediate rapid increase in the rate of protein synthesis ([3H]leucine incorporation) is observed within 15 min after the initiation of germination. The data, corrected for amino acid pool changes, reveal that the rate of protein synthesis reaches its peak at [Formula: see text], after which it decreases. A low level of RNA synthesis ([3H]uridine incorporation) is observed after 1 h and this rate increases markedly after 2 h. Analysis of the RNA species shows a low level of synthesis of all ribosomal RNA's which begins between 1 and 2 h and increases after 2 h. The synthesis of a heterogeneously distributed, poly(A)-containingfraction of RNA (presumptive mRNA) is initiated some time after 2 h and the synthesis of a small molecular weight species in the 4–5S region is observed after 3 h. Thus, it seems that Polysphondylium microcysts show sequentially initiated synthesis of RNA during germination.

Ultrastructural Changes During Formation and Germination of Microcysts in Polysphondylium Pallidum, a Cellular Slime Mould

1970 ◽  
Vol 7 (1) ◽  
pp. 285-305
Author(s):  
H. R. HOHL ◽  
L. Y. MIURA-SANTO ◽  
D. A. COTTER
Keyword(s):  
Cyst Wall ◽  
Ultrastructural Changes ◽  
Cell Periphery ◽  
Cytoplasmic Matrix ◽  
Cellular Slime Mould ◽  
Slime Mould ◽  
Fibrillar Material ◽  
Polysphondylium Pallidum ◽  
Cellular Slime ◽  
Mature Cyst

Ultrastructural changes during encystation of Polysphondylium pallidum, a cellular slime mould, include an increase in fibrillar material in the cytoplasmic matrix, the formation of cytoplasmic microprojections at the cell periphery and the occurrence of tiny vesicles and some larger vacuoles near the cell periphery. The cyst wall appears first as a fluffy, loose network of fibrils. In the mature cyst it consists of a dense inner and a somewhat looser outer layer. It contains inclusions of apparently cytoplasmic origin. Electron-dense material lines the cell periphery beneath the plasma membrane. Excystment of the myxamoeba is accompanied by a swelling of aggregated vacuoles and polyvesicular bodies, the disappearance of the peripheral cytoplasmic lining, and a general loosening of the wall texture. For a limited period the cisternae of the rough endoplasmic reticulum appear highly dilated. The loosened wall eventually breaks and the myxamoeba emerges by extending pseudopodia through the rupture, leaving the entire cyst wall behind.

Differentiation in roller tube cultures of wild-type and two cyclic AMP mutant strains of the cellular slime mould Polysphondylium pallidum

1982 ◽  
Vol 28 (10) ◽  
pp. 1143-1149
Author(s):  
Gary D. Paterno ◽  
Danton H. O'Day
Keyword(s):  
Cyclic Amp ◽  
Fruiting Body ◽  
Weight Fraction ◽  
Stalk Cell ◽  
Wild Type ◽  
Submerged Cultures ◽  
Slime Mould ◽  
Polysphondylium Pallidum ◽  
Exogenous Agents ◽  
Cellular Slime

Submerged cultures of wild-type Polysphondylium pallidum (WS320) undergo a developmental sequence in which cells agglutinate and form tight aggregates within which extensive stalk and some spore differentiation occurs. Development of submerged cultures of P. pallidum bears many similarities to fruiting body cultures except that differentiation occurs in the absence of morphogenesis. Here we extend the results of an earlier study of submerged cultures of P. pallidum WS320 (Paterno and O'Day. 1981. Can. J. Microbiol. 27: 924–936) by showing that these cultures respond to several exogenous agents (cyclic AMP, lithium chloride, ammonium chloride, colchicine, and concanavalin A) in the same way as slime mould fruiting body cultures. However, two mutants abnormal in cyclic AMP production which complement to form fruiting bodies on agar plates could not form normal submerged culture aggregates when mixed together. Complementation tests with mutant and wild-type cells also failed. The inability of the mutants (PN507 and PN518) to complement in submerged cultures suggests that their fruiting complementarity may be based on a morphogenetic event. A low molecular weight fraction from wild-type cells could enhance development and stalk cell differentiation in WS320 and one mutant, PN507, but not in PN518. Together these data reveal that submerged cultures can be utilized to test the effects of extracellular factors on development and used as a source for the isolation of factors that regulate cellular differentiation.

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