Hostname: page-component-848d4c4894-sjtt6 Total loading time: 0 Render date: 2024-06-19T23:27:16.614Z Has data issue: false hasContentIssue false

Genetic regulation of differentiation in Physarum polycephalum

Published online by Cambridge University Press:  14 April 2009

N. K. Honey
Affiliation:
Department of Biochemistry, University of Otago, Dunedin, New Zealand
R. T. M. Poulter
Affiliation:
Department of Biochemistry, University of Otago, Dunedin, New Zealand
D. M. Teale
Affiliation:
Department of Zoology, University of Otago, Dunedin, New Zealand

Summary

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.

Plasmodial formation in the Myxomycete Physarum polycephalum is controlled by a mating type (mt) locus. There are a number of different heterothallic mt alleles; and also a variant, mth, that allows plasmodial formation in pure clones. This paper reports an analysis of this differentiation system. The strain CL (mth) forms plasmodia in pure clones (i.e. it selfs). CL was mutagenized with NMG and 21 mutants unable to differentiate into amoebae were isolated. The mutants, together with CLd, fell into two complementation groups, twelve in difA and ten in difB. Both complementation groups are closely linked or allelic to the mt locus. difA represents a gene essential for plasmoclial formation, but it is suggested that difB represents a class of revertants to the mt2 heterothallic state. A model of the control of plasmodial formation is proposed in which the mt locus is suggested to code for the repressor of the difA gene. Genetic control is explained in terms of the dilution of allele-specific repressors.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1979

References

REFERENCES

Adler, P. N. & Holt, C. E. (1974). Genetic analysis in the Colonia strain of Physarum polycephalum: heterothallic strains that mate with and are partially isogenic to the Colonia strain. Genetics 78, 10511062.Google Scholar
Adler, P. N. & Holt, C. E. (1975). Mating type and the differentiated state in Physarum polycephalum. Developmental Biology 43, 240253.Google Scholar
Adler, P. N. & Holt, C. E. (1977). Mutations increasing asexual plasmodium formation in Physarum polycephalum. Genetics 87, 401420.Google Scholar
Anderson, R. W., Cooke, D. J. & Dee, J. (1976). Apogamic development of plasmodia in the Myxomycete Physarum polycephalum: a cinematographic analysis. Protoplasma 89, 2940.Google Scholar
Anderson, R. W. & Dee, J. (1977). Isolation and analysis of amoebal–plasmodial transition mutants in the Myxomycete Physarum polycephalum. Genetical Research 29, 2134.Google Scholar
Aston, R. J. (1978). Genetic Analysis of a Mycetozoan: Physarum polycephalum. B.Sc.(Hons) thesis, University of Otago.Google Scholar
Cabello, F., Timmis, K. & Cohen, S. N. (1976). Replication control in a composite plasmid constructed by in vitro linkage of two distinct replicons. Nature 259, 285290.Google Scholar
Collins, O. R. & Haskins, E. F. (1972). Genetics of somatic fusion in Physarum polycephalum: the PpII strain. Genetics 71, 6371.Google Scholar
Cooke, D. J. & Dee, J. (1974). Plasmodium formation without change in nuclear DNA content in Physarum po lycephalum. Genetical Research 23, 307317.Google Scholar
Cooke, D. J. & Dee, J. (1975). Methods for the isolation and analysis of plasmodial mutants in Physarum polycephalum. Genetical Research 24, 175187.Google Scholar
Davidow, L. S. & Holt, C. E. (1977). Mutants with decreased differentiation to plasmodia in Physarum polycephalum. Molecular and General Genetics 155, 291300.Google Scholar
Dee, J. (1966). Multiple alleles and other factors affecting plasmodium formation in the true slime mould, Physarum polycephalum. Schw. Journal of Protozoology 13, 610616.Google Scholar
Dee, J. (1973). Aims and techniques of genetic analysis in Physarum polycephalum. Berichte der Deutschen Botanischen Gesellschaft 86, 93121.Google Scholar
Dee, J. (1975). Slime moulds in biological research. Science Progress 62, 523542.Google Scholar
Dee, J. (1978). A gene unlinked to mating-type affecting crossing between strains of Physarum polycephalum. Genetical Research 31, 8592.Google Scholar
Dee, J. & Poulter, R. T. M. (1970). A gene conferring actidione resistance and abnormal morphology on Physarum polycephalum plasmodia. Genetical Research 15, 3541.Google Scholar
Honey, N. K., Poulter, R. T. M. & Teale, D. M. (1976). Evidence for an operon controlling differentiation in the eukaryotic slime-mould, Physarum polycephalum. Proceedings of the University of Otago Medical School 54, 1819.Google Scholar
Mohberg, J. (1977). Nuclear DNA content and chromosome numbers throughout the life cycle of the Colonia strain of the Myxomycete, Physarum polycephalum. Journal of Cell Science 24, 95108.CrossRefGoogle ScholarPubMed
Novick, R. P. & Hoppensteadt, F. C. (1978). On plasmid incompatibility. Plasmid 1, 421434.Google Scholar
Poulter, R. T. M. (1969). Senescence in the myxomycete Physarum polycephalum. Ph.D. thesis, University of Leicester.Google Scholar
Poulter, R. T. M. & Dee, J. (1968). Segregation of factors controlling fusion between plasmodia of the true slime mould Physarum polycephalum. Genetical Research 12, 7179.Google Scholar
Poulter, R. T. M. & Honey, N. K. (1977). Genetic analysis of a cross between two homothallic strains of Physarum polycephalum. Genetical Research 29, 5563.Google Scholar
Poulter, R. T. M., Honey, N. K. & Teale, D. M. (1977). The role of the self-sterile mating locus in the repressor-regulated control of differentiation of Physarum polycephalum. Heredity 39, 185. Abstract.Google Scholar
Pritchard, R. H., Barth, P. T. & Collins, J. (1969). Control of DNA synthesis in bacteria. Symposia of the Society for General Microbiology 19, 263297.Google Scholar
Uhlin, B. E. & Nordström, K. (1975). Plasmid incompatibility and control of replication: copy mutants of the R-factor R1 in Escherichia coli K12. Journal of Bacteriology 124, 641649.Google Scholar
Wheals, A. E. (1970). A homothallic strain of the Myxomycete Physarum polycephalum. Genetics 66, 623633.Google Scholar
Wheals, A. E. (1973). Developmental mutants in a homothallic strain of Physarum polycephalum. Genetical Research 21, 7986.Google Scholar