Voltage-Dependent K+ Channels as Targets of Osmosensing in Guard Cells
Year: 1998
Type: article
Abstract: Guard cell turgor responds to the osmogradient across the plasma membrane and controls the stomatal aperture. Here, we report that guard cells utilize voltage-dependent K+ channels as targets of the osmosensing pathway, providing a positive feedback mechanism for stomatal regulation. When exposed to a hypotonic condition, the inward K+ current (IKin) was highly activated, whereas the outward K+ current (IKout) was inactivated. In contrast, hypertonic conditions inactivated the IKin while activating IKout. Single-channel recording analyses indicated that an alteration in channel opening frequency was responsible for regulating IKin and IKout under different osmotic conditions. Further studies correlate osmoregulation of IKin with the pattern of organization of actin filaments, which may be a critical component in the osmosensing pathway in plant cells.
Source: The Plant Cell
Authors: Kun Liu, Sheng Luan
Institution: University of California, Berkeley
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2128293952