Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-23T00:29:53.012Z Has data issue: false hasContentIssue false
  • English
  • Français

A stable duplication as an intermediate in the selection of deletion mutants of phage T4

Published online by Cambridge University Press:  14 April 2009

C. van de Vate  and
N. Symonds
C. van de Vate
Affiliation:
School of Biological Sciences, University of Sussex, Brighton, Sussex
N. Symonds
Affiliation:
School of Biological Sciences, University of Sussex, Brighton, Sussex
Rights & Permissions [Opens in a new window]

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.

A selective procedure is described for the isolation of deletions in phage T4. This is based on the properties of partial diploids which possess a tandem duplication covering the rII region. The starting-point of the procedure is a particular s1231/3157 diploid which has a high segregation frequency and so possesses a long duplication. The replacement in this diploid of the large deletion 3157 by the small one 196 further increases the length of this duplication and removes the terminal redundancy of the resulting phage which are then non-viable. New compensating deletions which restore the terminal redundancy and thus the viability to these diploids are thereby selected. Nine new independent T4 deletions have been isolated by this procedure. The length of three has been estimated by terminal redundancy measurements and each found to be appreciably longer than the rII region. While developing the isolation procedure a key diploid intermediate was identified with the property that is was completely stable; that is, unlike typical diploids which continually generate haploid segregants during phage multiplications, this diploid strain produced no viable haploid segregants. This unexpected finding led us to examine the general problem of how tandem duplications can be stabilized. The solution we propose here is a structural one involving new stabilizing deletions which penetrate into one arm of the duplication removing certain essential genes. These stabilizing deletions are located in such a way that all haploid segregants formed by recombination are necessarily non-viable. Further investigations of the original stable diploid, and others isolated subsequently, validated this model for these phage diploids. It also led to the recognition of several novel genetic structures involving repeated DNA sequences which, together with the concept of the stabilizing deletions, could be of general significance.

Type
Research Article
Information
Genetics Research , Volume 23 , Issue 1 , February 1974 , pp. 87 - 105
Copyright
Copyright © Cambridge University Press 1974

References

REFERENCES

Adelberg, E. A. & Bergquist, P. (1972). The stabilization of episomal integration by genetic inversion: a general hypothesis. Proceedings of the National Academy of Sciences, U.S.A. 69, 2061–2065.Google Scholar
Benzer, S. (1962). On the topography of the genetic fine structure. Proceedings of the National Academy of Sciences, U.S.A. 47, 403–415.CrossRefGoogle Scholar
Bujard, H., Mazaitis, A. J. & Bautz, E. K. F. (1970). The size of the rII region of bacteriophage T4. Virology 42, 717–723.CrossRefGoogle ScholarPubMed
Dove, W. F. (1968). The extent of rII deletions in phage T4. Genetical Research 11, 215–219.Google Scholar
Drake, J. W. (1963). Mutational activation of a cistron fragment. Genetics 48, 767–773.Google Scholar
Edgar, R. S. & Wood, W. B. (1966). Morphogenesis of bacteriophage T4 in extracts of mutant-infected cells. Proceedings of the National Academy of Sciences, U.S.A. 55, 498–505.CrossRefGoogle ScholarPubMed
Fan, D. P. (1969). Deletions in limited homology recombination in Escherichia coli. Genetics 61, 351–361.CrossRefGoogle ScholarPubMed
Ohno, S. (1970). Evolution by Gene Duplication. Berlin, Heidelberg, New York: Springer-Verlag.CrossRefGoogle Scholar
Parma, D. H., Ingraham, L. J. & Snyder, M. (1972). Tandem duplications of the rII region of bacteriophage T4D. Genetics 74, 319–335.Google Scholar
Sederoff, R., Bolle, A. & Epstein, R. H. (1971). A method for the detection of specific T4 messenger RNAs by hybridization competition. Virology 45, 440–455.Google Scholar
Symonds, N., Van den Ende, P., Durston, A. & White, P. (1972). The structure of rII diploids of phage T4. Molecular and General Genetics 116, 223–238.CrossRefGoogle ScholarPubMed
Tessman, I. & Hall, D. H. (1967). Linkage of T4 genes controlling a series of steps in pyrimidine biosynthesis. Virology 31, 442–448.Google Scholar
Van den Ende, P. & Symonds, N. (1972). The isolation and characterization of a T4 mutant partially defective in recombination. Molecular and General Genetics 116, 239–247.CrossRefGoogle ScholarPubMed
Van de Vate, C. (1972). A stable duplication as an intermediate in selection for deletion mutants of phage T4. Report to the Royal Society.Google Scholar
Van de Vate, C, Van den Ende, P. & Symonds, N. (1974). A stable duplication of the rII region of bacteriophage T4. Genetical Research 23, 107–113.Google Scholar
Warner, H. R., Snustad, D. P., Jorgensen, S. E. & Koerner, J. F. (1970). Isolation of bacteriophage T4 mutants defective in the ability to degrade host deoxyribonucleic acid. Journal of Virology 5, 700–708.CrossRefGoogle ScholarPubMed
Warner, H. R., Snustad, D. P., Koerner, J. F. & Childs, J. D. (1972). Identification and genetic characterization of mutants of bacteriophage T4 defective in the ability to induce exonuclease. Virology 9, 399–407.Google Scholar
Weil, J. & Terzaghi, B. (1970). The correlated occurrence of duplications and deletions in phage T4. Virology 42, 234–237.Google Scholar
Weil, J., Terzaghi, B. & Crasemann, H. (1965). Partial diploidy in phage T4. Genetics 52, 683–693.Google Scholar