Referenced in: none

Automatically associated channels: Kv1.1 , Kv1.8 , Slo1

Title: Molecular cloning and partial functional characterization of Tsha3--a novel modulatory potassium channel alpha-subunit of trout CNS.

Authors: Tanja Piwowarski, Frank Panofen, Gunnar Jeserich

Journal, date & volume: Brain Res. Mol. Brain Res., 2004 May 19 , 124, 124-33

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/15135220

Abstract
A novel Shaker-related potassium channel subunit termed Tsha3 that is widely expressed in the CNS of trout was PCR-cloned and sequenced: its deduced amino acid sequence showed an extended N-terminal domain with a high proportion of negatively charged residues and possessed highest similarity with KCNA10, a human epithelial potassium channel. Upon heterologous expression in Sf21 cells, homomeric Tsha3 did not yield voltage-activated potassium channels but produced only ohmic currents that reversed at -15 mV. After co-expression with Tsha1, a novel outward rectifier current was generated that differed from homomeric Tsha1 by its slower kinetics of activation, its partial current inactivation, and its partial blockade by 5 mM TEA as well as 1 microM DTX. Co-immunoprecipitation studies using anti-Tsha3 antibodies confirmed that Tsha3 tightly bound with Tsha1 in co-infected Sf21 cells. As revealed from GFP- and DsRed-labeling studies, the pattern of distribution of Tsha1 was profoundly altered after co-infection with Tsha3 subunits.