Control of Neurospora crassa morphology by cyclic adenosine 3',5' monophosphate and dibutyryl cyclic adenosine 3',5' monophosphate

Abstract

The role of cyclic adenosine 3',5' monophosphate (cyclic AMP) in the control of the Neurospora asexual life cycle was studied. Endogenous cyclic AMP levels were 10 to 20 times higher in strains having the wild type cr-1 allele than in those carrying the mutated allele. In a wild type strain these levels remained constant throughout the entire growth period in shaken liquid cultures, except during a short period at the beginning of the stationary growth phase. In this period a marked increase in the cyclic nucleotide level was observed. The culture of cr-1 mutant strains in the presence of cyclic AMP or its dibutyryl derivative restores some morphological properties characteristic of wild type strains. Specifically these cyclic nucleotides stimulated the rate of mycelial elongation, as well as the differentiation of aerial hyphae.