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Dilution of gene products in the cytoplasm of heterokaryons in Coprinus lagopus

Published online by Cambridge University Press:  14 April 2009

Lorna A. Casselton  and
D. Lewis
Lorna A. Casselton
Affiliation:
Department of Botany, University College London
D. Lewis
Affiliation:
Department of Botany, University College London
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(a) Coprinus lagopus has in nature both a monokaryon with one haploid nucleus per cell and a dikaryon with two haploid nuclei per cell. It also has in experiment both a heterokaryon with two types of nuclei distributed irregularly in the mycelium and a diploid monokaryon with one diploid nucleus per cell.

(b) Two pairs of linked recessive auxotrophic mutants, me-5 ad-8 and adhis-1 chol-1 have been combined in two different sets of multiple heterogenotes so that in the dikaryon and heterokaryon the + (active) alleles of the four genes are distributed equally in the two component nuclei. In one combination the linked genes are in trans and in the other they are in cis arrangement in diploid, dikaryon and heterokaryon.

(c) Complementation between the + genes, as measured by growth on minimal and complete media, was complete in the diploid and dikaryon but was only partial in the heterokaryon.

(d) A similar comparison of a recessive suppressor of the mutant me-1 revealed that the recessive gene was not expressed and therefore was fully recessive in the diploid and dikaryon but was only partially recessive in the heterokaryon.

(e) The exact similarity of complementation of the structural genes of the auxotrophic mutants and the recessiveness of the me-1 suppressor in diploids and dikaryons exclude a localization of gene interaction in the nucleus. In a heterokaryon cytoplasmic dilution of the product of a dominant gene can occur and has the effect of producing a phenotypic difference between heterokaryons and diploids.

Type
Research Article
Information
Genetics Research , Volume 9 , Issue 1 , February 1967 , pp. 63 - 71
Copyright
Copyright © Cambridge University Press 1967

References

REFERENCES

Apirion, D. (1966). Recessive mutants at unlinked loci which complement in diploids but not in heterokaryons of Aspergillus nidulans. Genetics, 53, 935–941.CrossRefGoogle Scholar
Ayling, P. D., (1965). Genetics of suppressors of methionine mutants in Aspergillus nidulans. Ph.D. Thesis, University of London.Google Scholar
Casselton, L. A. (1965). The production and behaviour of diploids of Coprinus lagopus. Genet. Res. 6, 190–208.CrossRefGoogle ScholarPubMed
Clutterbuck, A. J. & Roper, J. A. (1966). A direct determination of nuclear distribution in heterokaryons of Aspergillus nidulans. Genet. Res. 7, 185–194.CrossRefGoogle Scholar
Jinks, J. L. (1952). Heterokaryosis: a system of adaptation in wild fungi. Proc. R. Soc. B, 140, 83–99.Google ScholarPubMed
Lewis, D. (1961). Genetical analysis of methionine suppressors in Coprinus. Genet. Res. 2, 141–155.CrossRefGoogle Scholar
Luig, N. H. (1962). Recessive suppressors in A. nidulans closely linked to an auxotrophic mutant which they suppress. Genet. Res. 3, 331–332, see also Pontecorvo (1963).CrossRefGoogle Scholar
Pontecorvo, G. (1952). Genetical analysis of cell organization. Symp. Soc. exp. Biol. 6, 218–229.Google Scholar
Pontecorvo, G. (1963). Microbial genetics; retrospect and prospect. Proc. R. Soc. B, 158, 1–23.Google Scholar
Roberts, C. F. (1964). Complementation in balanced heterokaryons and heterozygous diploids of Aspergillus nidulans. Genet. Res. 5, 211–229.CrossRefGoogle Scholar
Swiezynski, K. M. & Day, P. R. (1960). Migration of nuclei in Coprinus lagopus. Genet. Res. 1, 129–139.CrossRefGoogle Scholar
Warr, J. R. & Roper, J. A. (1965). Resistance to various inhibitors in Aspergillus nidulans. J. gen. Microbiol. 40, 273–281.CrossRefGoogle ScholarPubMed