Ca. De Pinho et al., Mobilisation of trehalose in mutants of the cyclic AMP signalling pathway,cr-1 (CRISP-1) and mcb (microcycle conidiation), of Neurospora crassa, FEMS MICROB, 199(1), 2001, pp. 85-89
The influence of the cAMP-signalling pathway on the metabolism of trehalose
in Neurospora crassa was investigated. The changes in intracellular trehal
ose concentration were measured in two mutants affected in components of th
e cAMP-signalling pathway. tr-l (crisp-l), deficient in adenylyl cyclase ac
tivity, and, mch (microcyclic conidiation), deficient in the regulatory sub
unit of PKA. Rapid mobilisation of intracellular trehalose in the wild-type
occurred, either at the onset of germination, or after a heat shock, and b
y carbon starvation. Mutant cr-I failed to mobilise trehalose at germinatio
n, but behaved almost normally after a heat shock, or during carbon starvat
ion. On the other hand, the levels of trehalose in mcb fell to values much
lower than in the wild-type at germination, but accumulated trehalose norma
lly during a heat shock. These results are consistent with the involvement
of cAMP in the activation of the neutral trehalase at the onset of germinat
ion. However, the control of the enzyme under the other physiological condi
tions which also promote mobilisation of intracellular trehalose was appare
ntly independent of cAMP-signalling. (C) 2001 Published by Elsevier Science
B.V. on behalf of the Federation of European Microbiological Societies.