Cyclic AMP-dependent, constitutive thermotolerance in the adenylate cyclase-deficient cr-1 (crisp) mutant of Neurospora crassa

Curr Genet. 1988 May;13(5):451-4. doi: 10.1007/BF00365668.


We investigated the heat shock response of the adenylate cyclase deficient mutant cr-1 (crisp) of Neurospora crassa. This strain was observed to be much more resistant to a lethal temperature of 50 degrees C than the wild type. This constitutive thermotolerance was absent in cr-1 conidiospores raised on cyclic AMP (cAMP, 2.5 mM) supplemented solid medium, but was partially restored when the conidiospores were germinated at 30 degrees C, a temperature which fails to induce thermotolerance in the wild-type strain. Two other crisp-like Neurospora mutants, cr-2 and cr-3 which, in contrast to cr-1, contain normal levels of cAMP, did not exhibit the thermotolerance phenomenon observed for cr-1. A cr-1, pe, fl (crisp-microconidial) strain also lacked the ability to tolerate a lethal heat treatment. Our results demonstrate that the adenylate cyclase deficient cr-1 mutant of Neurospora crassa expresses a constitutive thermotolerant phenotype as a consequence of its primary genetic defect: low levels of cAMP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenylyl Cyclases / genetics*
  • Chromosome Deletion
  • Cyclic AMP / pharmacology*
  • Genes
  • Genes, Fungal
  • Kinetics
  • Mutation*
  • Neurospora / genetics*
  • Neurospora crassa / drug effects
  • Neurospora crassa / genetics*
  • Neurospora crassa / growth & development
  • Temperature


  • Cyclic AMP
  • Adenylyl Cyclases