Tethered Toxin (IMAGE) University of California - Irvine Caption The tethered toxin (T-HmK) is drawn free and bound to a potassium channel (blue) expressed in the cell membrane. The reaction volume that a T-HmK can visit (two-headed arrow) is determined by the combined lengths of the flexible peptide linker, the GPI anchor, and the diameter of HmK toxin. The lower panel shows the expression construct design. Credit UCI School of Medicine Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.