HERG

The hERG channel ( Abbreviation for. Human ether -a -go-go related gene ) is a voltage- activated, inwardly rectifying potassium channel in cardiac myocytes.

Properties

The channel consists of four subunits, each with six transmembrane domains and is responsible for the partial repolarization by a rapid potassium efflux IKr during the action potential in the heart. The hERG channel has an effect on cell division and apoptosis.

Structure

The hERG potassium channels may be either homo-or heterotetramers of α - subunits or heterotetramers of α - and β - subunits. As α - unit, the proteins Kv11.1 ( Gen: KCNH2 ), Kv11.2 ( KCNH6 ) act Kv11.3 ( KCNH7 ) or Kv7.1 ( KCNQ1 ) and MinK ( KCNE1 ), MiRP1 ( KCNE2 ) and MiRP2 ( KCNE3 ) are potential β - units. Not all combinations are allowed.

Pathophysiology

Changes in the channel leading to long or short QT syndrome. Since the repolarization of the action potential is changed, dangerous heart rhythms (arrhythmias ) occur. After some pharmaceuticals have led to an unintended effect on the HERG channel requires the U.S. regulatory authority, that all new drugs be tested for HERG activity. The tremendous demand for these tests was one of the main driving forces behind the development of automated ion channel analysis.

Naming

The gene coding for the protein gene is located in the q35 - q36 locus Chr.7, ie on the q arm of human chromosome 7 in the section 35 and 36, the gene is related to the ether - O - go-go gene found in Drosophila. Mutations in this gene solved in the affected flies under ether from a Fußzucken, reminiscent of the famous dances from the legendary at the time rock club Whisky A Go-Go. The naming was made by William D. Kaplan in the 1960s.