Part:BBa_K2263001

Part K2263001 is a mammalian membrane protein gene, and is interesting for projects in the field of electrophysiology.

This part encodes the human Ether-à-go-go-Related Gene, also known as hERG and, alternatively, as KCNH2. Like HCN (see the related part: https://parts.igem.org/Part:BBa_K2263000 ), it is associated with the rhythm generated in natural sinus node cells. It encodes the K+-channel responsible for the repolarisation during the cardiac action potential. Furthermore, the hERG-encoded protein Kv11.1 is of great medical and pharmaceutical importance, as inhibition of this protein is associated with the dangerous long QT syndrome, which may result in fainting, seizures and even sudden death. (1) Therefore, hERG inhibition is a major antitarget in drug development, and all drugs have to be tested for hERG inhibition in early development.

In our project, we used hERG as a part of the system that creates oscillation in HEK cells. (Read more about that on our wiki: http://2017.igem.org/Team:KU_Leuven ) In this project, we used the hERG gene encoded by the wildtype sequence, and not the biobrick-compatible version we present here. However, we have made a great effort to introduce the silent mutations in a smart and codon-optimising way, and we hope other teams will use and characterise this part in the future.

For teams that want to use this biobrick, we suggest to clone the part into a mammalian expression vector, followed by an internal ribosome entry site (IRES) and a fluorescent marker. In this case, the part and the marker are transcribed at the same time, but translated independently. In such a system, the marker indicates that the part is transcribed in the cell, but they are not physically linked. This is beneficial, as a linked marker protein may affect or hinder the protein function.

IRES sequences and fluorescent markers can be found throughout the registry. Furthermore, many labs using mammalian expression vectors will own empty vectors containing an IRES and a marker. You could clone this part directly into such a vector.

(1) Michael C. Sanguinetti, Martin Tristani-Firouzi. hERG potassium channels and cardiac arrhythmia. (2006) Nature 440, 463-469