Page 52 - Q. Neuroscience

[Q. Neuroscience-31]

The regulation of voltage-gated potassium channel by STK10

in hippocampal neurons

Sang Yeon Lee¹, Kang-Sik Park¹

¹Department of Physiology, Kyung Hee University College of Medicine, Seoul 02447, South Korea

The voltage-gated potassium channel Kv2.1 is localized in high density surface clusters on the soma, proximal
dendrites, and axon initial segment (AIS). The serine/threonine-protein kinase 10 (STK10) phosphorylates ezrin,
radixin, and moesin (the ERM proteins). The ERM proteins have a critical role in reorganizing the cytoskeleton. Here,

we show that Kv2.1 in the rat brain is associated with STK10 using mass spectrometry. The STK10 in neuron reveals

overall puncta form in the cytoplasm or column form on the cell surface. In neurons transfected with STK10, there
was an increase in the size and number of the somato-dendritic membrane clusters of Kv2.1. The knockdown of
STK10 demonstrated that Kv2.1 is not localized in the somato-dendritic membrane, but instead retains its clusters

in the AIS. Inhibition of ERM phosphorylation by rapamycin treatment suppressed membrane expression of Kv2.1
in neurons transfected with STK10. On the other hand, glutamate treatment inducing ERM phosphorylation in

neurons transfected with STK10 increased membrane expression of Kv2.1. Together our results indicate that the
membrane expression of Kv2.1 is regulated by STK10. This is done so through the method of phosphorylation of

ERM proteins, which results in the reorganization of the cytoskeleton.