Molecular and General Genetics MGG

, Volume 185, Issue 1, pp 132–135 | Cite as

Partial characterization of 5-fluoropyrimidine-resistant mutants of Neurospora crassa

  • Frank P. Buxton
  • Alan Radford


The primary lesion in a number of 5-fluoropyrimidine resistant mutants of Neurospora crassa has been identified. ud-1 mutants, previously designated fdu-2, are deficient in nucleoside uptake and show extensive intragenic complementation. uc-4 mutants lack uracil phosphoribosyl transferase with no complementation between 23 alleles. udk mutants lack uridine kinase activity. fdu-2 mutants affect the repression of the first two de novo pyrimidine biosynthetic enzymes, have no detectable uridine kinase activity and show decreased uridine uptake. Accordingly, fdu-2 may be involved in the regulation of pyrimidine uptake, salvage and de novo synthesis.


Enzyme Pyrimidine Nucleoside Uracil Uridine 
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Copyright information

© Springer-Verlag 1982

Authors and Affiliations

  • Frank P. Buxton
    • 1
  • Alan Radford
    • 1
  1. 1.Department of GeneticsLeeds UniversityLeedsUK

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