[Analysis of the Ca2+ response of mycelial fungi to external effects by the recombinant aequorin method].
Using the mutant strain Aspergillus awamori 66A producing a recombinant Ca2+-dependent photosensitive protein aequorin, the dynamics of Ca2+ was studied for the first time in the cytosol of the micromycetes exposed to stressful factors, such as an increase in extracellular Ca2+ to 50 mM, hypoosmotic shock, and mechanical shock. Cell response to stress proved to involve an increase in the Ca2+ concentration in the cytosol, which was determined from the amplitude of aequorin luminescence and the time of the amplitude enhancement and relaxation. The level of Ca2+ response depended on the physiological stimulus. Inhibitory analysis with various agents that block Ca2+ channels and with agonists that specifically enhance the activity of the channels suggested that (1) the level of Ca2+ in the cytosol of micromycetes increases in response to stress because of the ion influx from both the growth medium and intracellular reservoirs and (2) the potential-dependent transport systems play the major role in the Ca2+ influx into the cytosol of the micromycete cells.
Kozlova
O V
OV
Egorov
S Iu
SIu
Kupriianova-Ashina
F G
FG
Read
N
N
El'-Registan
G I
GI
D000331:Aequorin / Q000096:biosynthesis / Q000235:genetics; D001230:Aspergillus / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015220:Calcium Channels / Q000378:metabolism; D002122:Calcium Chloride / Q000494:pharmacology; D003600:Cytosol / Q000378:metabolism; D009997:Osmotic Pressure; D011994:Recombinant Proteins / Q000096:biosynthesis
D015220:Calcium Channels; D011994:Recombinant Proteins; D000331:Aequorin; D002122:Calcium Chloride