TY  - JOUR
A1  - Dindas, Julian
A1  - Dreyer, Ingo
A1  - Huang, Shouguang
A1  - Hedrich, Rainer
A1  - Roelfsema, M. Rob G.
T1  - A voltage-dependent Ca\(^{2+}\) homeostat operates in the plant vacuolar membrane
JF  - New Phytologist
N2  - Cytosolic calcium signals are evoked by a large variety of biotic and abiotic stimuli and play an important role in cellular and long distance signalling in plants. While the function of the plasma membrane in cytosolic Ca\(^{2+}\) signalling has been intensively studied, the role of the vacuolar membrane remains elusive.
A newly developed vacuolar voltage clamp technique was used in combination with live-cell imaging, to study the role of the vacuolar membrane in Ca\(^{2+}\) and pH homeostasis of bulging root hair cells of Arabidopsis.
Depolarisation of the vacuolar membrane caused a rapid increase in the Ca\(^{2+}\) concentration and alkalised the cytosol, while hyperpolarisation led to the opposite responses.
The relationship between the vacuolar membrane potential, the cytosolic pH and Ca2+ concentration suggests that a vacuolar H\(^{+}\)/Ca\(^{2+}\) exchange mechanism plays a central role in cytosolic Ca2+ homeostasis. Mathematical modelling further suggests that the voltage-dependent vacuolar Ca\(^{2+}\) homeostat could contribute to calcium signalling when coupled to a recently discovered K\(^{+}\) channel-dependent module for electrical excitability of the vacuolar membrane.
KW  - voltage clamp
KW  - Arabidopsis thaliana
KW  - calcium signalling
KW  - computational cell biology
KW  - cpYFP cytosolic pH reporter
KW  - R-GECO1 cytosolic Ca\(^{2+}\) reporter
KW  - TPC1 channel
KW  - vacuolar membrane
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259627
VL  - 230
IS  - 4
ER  -