Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-11-20T06:25:04.533Z Has data issue: false hasContentIssue false

Recombination in a Myxomycete, Physarum polycephalum Schw.

Published online by Cambridge University Press:  14 April 2009

Jennifer Dee
Affiliation:
Department of Genetics, University of Glasgow
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

1. Techniques were developed to facilitate genetic analysis of a Myxomycete, Physarum polycephalum. The uninucleate cells that form part of the life-cycle (the ‘amoebae’), in two-membered culture with Pseudomonas fluorescens, were found to be suitable for handling by some of the standard techniques of microbial genetics, including plating.

2. As reported previously, a single-factor (+/−) mating-type system was discovered in P. polycephalum controlling the formation of plasmodia by the amoebae. Plasmodia are formed only when amoebae of different mating-type are mixed together. A single spore gives a culture of amoebae of one mating-type only, which may be assumed to be a clone.

3. A strain of amoebae resistant to emetine hydrochloride was isolated and was found to maintain its resistance through many subcultures in the absence of the drug.

4. A cross was made between the emetine-resistant strain (mating-type −) and an emetine-sensitive strain (mating-type +). Spores obtained from the hybrid plasmodium were plated and four sets of isolates of amoebae were made from these spores, and separately tested for mating-type and for emetine resistance.

5. The results of testing these isolates agree with the hypothesis that mating-type and emetine resistance are determined by pairs of alleles at two unlinked loci provided that factors disturbing the segregation for emetine resistance are assumed to be present.

6. Consideration of factors that could have disturbed the segregation for emetine resistance shows that selfing did not occur in the cross but that some misclassification for emetine resistance probably did occur.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1962

References

REFERENCES

Daniel, J. W. & Rusch, H. P. (1961). The pure culture of Physarum polycephalum on a partially defined soluble medium. J. gen. Microbiol. 25, 4759.CrossRefGoogle ScholarPubMed
Dee, J. (1960 a). A mating-type system in an acellular slime mould. Nature, Lond., 185, 780781.CrossRefGoogle Scholar
Dee, J. (1960 b). Genetic Analysis of a Myxomycete. Ph.D. thesis. (University of Glasgow).Google Scholar
Howard, F. L. (1931 a). The life history of Physarum polycephalum. Amer. J. Bot. 18, 116133.CrossRefGoogle Scholar
Howard, F. L. (1931 b). Laboratory cultivation of myxomycete plasmodia. Amer. J. Bot. 18, 624628.CrossRefGoogle Scholar
Kerr, N. S. & Sussman, M. (1958). Clonal development of the true slime mould, Didymium nigripes. J. gen. Microbiol. 19, 173177.CrossRefGoogle ScholarPubMed
Martin, G. W. (1940). The Myxomycetes. Bot. Rev. 6, 356388.CrossRefGoogle Scholar
Martin, G. W. (1949). The Myxomycetes. N. Amer. Flora, I, 1, 1190.Google Scholar
Nygaard, O. F., Guttes, S. & Rusch, H. P. (1960). Nucleic acid metabolism in. a slime mould with synchronous mitosis. Biochim. biophys. Acta, 38, 298306.CrossRefGoogle Scholar
Ross, I. K. (1957). Syngamy and plasmodium formation in the Myxogastres. Amer. J. Bot. 44, 843850.CrossRefGoogle Scholar
Ross, I. K. (1961). Further studies on meiosis in the Myxomycetes. Amer. J. Bot. 48, 244248.CrossRefGoogle Scholar
Rusch, H. P. (1959). Organization of growth processes. UNESCO Symposium on Biological Organization (Pergamon Press), pp. 263274.Google Scholar
Stosch, H. A. von (1935). Untersuchungen über die Entwicklungsgeschichte der Myxomyceten. Sexualität und Apogamie bei Didymiaceen. Planta, 23, 623656.CrossRefGoogle Scholar
Wilson, C. M. & Ross, I. K. (1955). Meiosis in the Myxomycetes. Amer. J. Bot. 42, 743749.CrossRefGoogle Scholar