Extrachromosomal Mu

  • Venkatesan Sundaresan
Part of the Basic Life Sciences book series (BLSC, volume 47)


Maize lines known as Robertson’s Mutator (Mu) lines generate unstable recessive mutations at high rates. These lines carry actively transposing copies of the elements Mu1 and Mu1.7. We have discovered extrachromosomal forms of the Mu1 and Mu1.7 transposons. We have shown that these molecules are most likely covalently closed circular DNA (ccDNA). Further, we find that their occurrence is correlated with Mu transposition so that they are probably generated during Mu transposition as transposition intermediates, abortive intermediates, or excision products. Our data suggest that Mu1 and Mu1.7 circles account for a significant fraction of the total ccDNA found in Mutator lines, but that other Mu-homologous circles are also present in these lines.


Maize Line Barley Stripe Mosaic Virus Tn10 Transposase Excision Product Circular Fraction 
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  1. 1.
    Alleman, M., and M. Freeling (1986) Genetics 112:107–119.PubMedGoogle Scholar
  2. 2.
    Barker, R.F., D.V. Thompson, D.R. Talbot, J. Swanson, and J. Bennetzen (1984) Nucl. Acids Res. 12:5955–5967.PubMedCrossRefGoogle Scholar
  3. 3.
    Bender, J., and N. Kleckner (1986) Cell 45:801–815.PubMedCrossRefGoogle Scholar
  4. 4.
    Bennetzen, J.L. (1985) In Plant Genetics: UCLA Symposia in Molecular Biology, New Series, M. Freeling, ed. Liss, New York, Vol. 35, pp. 343–354.Google Scholar
  5. 5.
    Cappello, J., K. Handelsman, and H.F. Lodish (1985) Cell 43:105–115.PubMedCrossRefGoogle Scholar
  6. 6.
    Chandler, V.L., and V. Walbot (1986) Proc. Natl. Acad. Sci., USA 83:1767–1771.PubMedCrossRefGoogle Scholar
  7. 7.
    Chen, C.H., K.K. Oishi, B. Kloeckener-Gruissem, and M. Freeling (1987) Genetics 116:469–477.PubMedGoogle Scholar
  8. 8.
    Flavell, A.J., and C. Brierley (1986) Nucl. Acids Res. 14:3659–3669.PubMedCrossRefGoogle Scholar
  9. 9.
    Flavell, A.J., and D. Isch-Horowicz (1981) Nature, London 292:591–595.CrossRefGoogle Scholar
  10. 10.
    Freeling, M. (1984) An. Rev. Plant Physiol. 35:277–298.CrossRefGoogle Scholar
  11. 11.
    Johns, M.A., J. Mottinger, and M. Freeling (1985) EMBO J. 4:1093–1102.PubMedGoogle Scholar
  12. 12.
    Kemble, R.J., and J.R. Bedbrook (1980) Nature London 284:565–566.CrossRefGoogle Scholar
  13. 13.
    Levings, C.S., III, D.M. Shah, W.W.L. Hu, D.R. Pring, and D.H. Timothy (1979) In Extrachromosomal DNA, ICN-UCLA Symposium on Molecular and Cellular Biology, D.J. Cummings, P. Borst, I.G. David, and S.M. Weissman, eds. Academic Press, New York, Vol. 16, pp. 63–73.Google Scholar
  14. 14.
    Lillis, M., and M. Freeling (1986) Trends in Genet. 2:183–188.CrossRefGoogle Scholar
  15. 15.
    Morisato, D., and N. Kleckner (1984) Cell 39:181–190.PubMedCrossRefGoogle Scholar
  16. 16.
    Morisato, D., and N. Kleckner (1987) Cell (in press).Google Scholar
  17. 17.
    Mossie, K.G., M.W. Young, and H.E. Varmus (1985) J. Molec. Biol. 182:31–48.PubMedCrossRefGoogle Scholar
  18. 18.
    Robertson, D.S. (1978) Mutat. Res. 51:21–28.CrossRefGoogle Scholar
  19. 19.
    Robertson, D.S. (1980) Genetics 94:969–978.PubMedGoogle Scholar
  20. 20.
    Robertson, D.S. (1983) Molec. Gen. Genet. 191:86–90.CrossRefGoogle Scholar
  21. 21.
    Robertson, D.S. (1986) Genetics 113:765–773.PubMedGoogle Scholar
  22. 22.
    Rose, A.M., and T.P. Snutch (1984) Nature, London 311:485–486.CrossRefGoogle Scholar
  23. 23.
    Ruan, K.S., and S.W. Emmons (1984) Proc. Natl. Acad. Sci., USA 81:4018–4022.PubMedCrossRefGoogle Scholar
  24. 24.
    Saedler, H., and P. Nevers (1985) EMBO J. 4:585–590.PubMedGoogle Scholar
  25. 25.
    Shapiro, J.A. (1979) Proc. Natl. Acad. Sci., USA 76:1933–1937.PubMedCrossRefGoogle Scholar
  26. 26.
    Strommer, J.N., S. Hake, J. Bennetzen, W.C. Taylor, and M. Freeling (1982) Nature, London 300:542–544.CrossRefGoogle Scholar
  27. 27.
    Sundaresan, V., and M. Freeling (1987) Proc. Natl. Acad. Sci., USA 84:4924–4928.PubMedCrossRefGoogle Scholar
  28. 28.
    Taylor, L.P., V.L. Chandler, and V. Walbot (1986) Maydica 31:31–45.Google Scholar
  29. 29.
    Walbot, V., and C.A. Cullis (1985) An. Rev. Plant Physiol. 36:367–396.CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1988

Authors and Affiliations

  • Venkatesan Sundaresan
    • 1
  1. 1.Cold Spring Harbor LaboratoryCold Spring HarborUSA

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