Orsolya Vörös and her colleagues under the supervision of Peter Hajdu studied the molecular background of the T lymphocyte’s Kv1.3 ion channel operation and targeting to the membrane. Their results showed that the C-terminal region of Kv1.3 right after the S6 helix (the HRET motif) plays crucial role in the activation gating and ion-conduction but not in trafficking to the plasma membrane. The presence of the C-terminus distal part had no impact on the trafficking to the plasma membrane and biophysical features of Kv1.3 unlike it was described before (Scientific Reports, 8:5937, https://www.nature.com/articles/s41598-018-24159-8)
The putative interaction between the HRET motif and activation-regulating S4-S5 linker activation based on the homology modeling in Kv1.2. (Left) Ribbon representation of two opposing Kv1.2 subunits. S4-S5 linker helical region is shown in blue (boxed with red rectangle) and HRET region is represented with orange helix (framed with green ellipse with dashed line). (Right) Predicted interaction between the S4-S5 linker and the HRET region via the possible coupling between Lys312 (330 in Kv1.3) and Glu420 (438 in Kv1.3) that is required for the Kv1.3 activation