Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-05T04:12:31.908Z Has data issue: false hasContentIssue false
  • English
  • Français

Suppression of ‘purple’ in Coprinus lagopus—an anomalous genetic situation

Published online by Cambridge University Press:  14 April 2009

D. H. Morgan
D. H. Morgan
Affiliation:
Department of Botany, University College London*

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.

The spontaneous reversion to white of three purple mutants of Coprinus lagopus has been demonstrated to be due to suppression. Forty-one of the fifty suppressed purples isolated were crossed to wild-type and all crosses gave fewer than 25% purple progeny, i.e. all the suppressors appeared to be linked to the gene suppressed. Values for the percentage of purples segregated from these crosses varied continuously from 0% to nearly 20%. The functional relationships of the fifty suppressors were investigated by the technique of complementation in dicaryons. The pattern of results formally indicate two suppressor loci with extensive inter-allelic complementation at one of them. The functional allelism indicated by the complementation results is not compatible, in conventional terms, with the apparent positional spread of the suppressors. Several possible explanations are discussed but more data are required before a choice can be made between them. It seems most probable that the same genetic entity is involved in each independent event of suppression and that the characteristic segregations of purples from crosses of suppressed purples with wild-type will have to be explained in terms other than of normal recombination.

Type
Research Article
Information
Genetics Research , Volume 7 , Issue 2 , April 1966 , pp. 195 - 206
Copyright
Copyright © Cambridge University Press 1966

References

REFERENCES

Brink, R. A. (1960). Paramutation and chromosome organization. Q. Rev. Biol. 35, 120–137.Google Scholar
Dawson, G. W. P. & Smith-Keary, P. F. (1963). Episomic control of mutation in Salmonella typhimurium. Heredity, Lond. 18, 1–20.CrossRefGoogle ScholarPubMed
Day, P. R. (1959). A cytoplasmically controlled abnormality of the tetrads of Coprinus lagopua. Heredity, Lond. 13, 81–87.Google Scholar
Fincham, J. R. S. (1965). Genetic Complementation New York: W. A. Benjamin Inc. (In press.)Google Scholar
Gibson, J. B. & Thoday, J. M. (1962). An apparent 20 map unit position effect. Nature, Lond. 196, 661–662.CrossRefGoogle Scholar
Jacob, F. & Monod, J. (1961). Genetic regulatory mechanisms in the synthesis of proteins. J. molec. Biol. 3, 318–365.CrossRefGoogle ScholarPubMed
Lewis, D. (1961). Genetic analysis of methionine suppressors in Coprinus lagopus. Genet. Res. 2, 141–155.CrossRefGoogle Scholar
Lewis, E. B. (1950). The phenomenon of position effect. Adv. Genet. 3, 73–115.Google Scholar
McClintock, B. (1956). Controlling elements and the gene. Cold Spring Harb. Symp. quant. Biol. 21, 197–216.CrossRefGoogle ScholarPubMed