Current Genetics

, Volume 34, Issue 6, pp 478–485

Functional characterization of SOR1, a gene required for resistance to photosensitizing toxins in the fungus Cercospora nicotianae

  • Marilyn Ehrenshaft
  • Kuang-Ren Chung
  • Anne E. Jenns
  • M. E. Daub
ORIGINAL PAPER

DOI: 10.1007/s002940050423

Cite this article as:
Ehrenshaft, M., Chung, KR., Jenns, A. et al. Curr Genet (1999) 34: 478. doi:10.1007/s002940050423

Abstract

The Cercospora nicotianae SOR1 gene is required for resistance to singlet oxygen-generating photosensitizers. SOR1 was characterized in the wild-type and in five photosensitizer-sensitive mutant strains which are complemented to photosensitizer resistance by transformation with SOR1. Sequence analysis determined that three of the mutants contain SOR1 copies with mutations encoding substitutions in the protein-coding sequence; however, two other mutants had wild-type SOR1 protein and promoter sequences. All five mutants accumulate SOR1 mRNA at levels comparable to that of the wild-type strain. In the wild-type strain, SOR1 accumulation is enhanced two-fold by light, but is unaffected by the presence of cercosporin, the photosensitizer synthesized by C. nicotianae. Southern analysis indicates that SOR1 is present in other fungi that synthesize structurally related perylenequinone photosensitizers.

Key words Photosensitizer resistanceSinglet oxygen resistanceCercospora spp.Cercosporin

Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Marilyn Ehrenshaft
    • 1
  • Kuang-Ren Chung
    • 1
  • Anne E. Jenns
    • 1
  • M. E. Daub
    • 1
  1. 1.Department of Plant Pathology, North Carolina State University, Raleigh, NC 27695-7616, USA e-mail: margaret daub@ncsu.edu Fax: +1-919-515 7716US