• SyncroPatch 384

    Next level versatility and flexibility
  • SyncroPatch 384

    True HTS and GigaOhm seals
  • SyncroPatch 384

    Your multi purpose instrument
  • SyncroPatch 384

    Powerful analysis software
  • SyncroPatch 384

    Assay flexibility via high tech
  • SyncroPatch 384

    Heating and cooling of solutions, cells and patch clamp sites

2020 - High-throughput discovery of trafficking-deficient variants in the cardiac potassium channel KCNH2: Deep mutational scan of KCNH2 trafficking

 icon sp96   SyncroPatch 384PE (a predecessor model of the SyncroPatch 384i instrument) Pre-publication in bioRxiv Biology (2020)

Kozek K.A., Glazer A.M., Ng C.-A., Blackwell D., Egly C.L., Vanags L.R., Blair M., Mitchell D., Matreyek K.A., Fowler D.M., Knollmann B.C., Vandenberg J., Roden D.M., Kroncke B.M.

bioRxiv Biology (2020) doi.org/10.1101/2020.02.17.952606


KCHN2 encodes the KV11.1 potassium channel responsible for IKr, a major repolarization current during the cardiomyocyte action potential. Variants in KCNH2 that decrease IKr can cause Type 2 Long QT syndrome, usually due to mistrafficking to the cell surface. Accurately discriminating between variants with normal and abnormal trafficking would help clinicians identify and treat individuals at risk of a major cardiac event. The volume of reported non-synonymous KCNH2 variants preclude the use of conventional electrophysiologic methods for functional study.

To report a high-throughput, multiplexed screening method for KCNH2 genetic variants capable of measuring the cell surface abundance of hundreds of missense variants in KCNH2.

We develop a method to quantitate KCNH2 variant trafficking on a pilot region of 11 residues in the S5 helix, and generate trafficking scores for 220/231 missense variants in this region.

For 5/5 variants, high-throughput trafficking scores validated when tested in single variant flow cytometry and confocal microscopy experiments. We additionally compare our results with planar patch electrophysiology and find that loss-of-trafficking variants do not produce IKr, but that some variants which traffic normally may still be functionally compromised.

Here, we describe a new method for detecting trafficking-deficient variants in KCNH2 in a multiplexed assay. This new method accurately generates trafficking data for variants in KCNH2 and can be readily extended to all residues in Kv11.1 and to other cell surface proteins.

Clinical Implications:
Hundreds of KCNH2 variants have been observed to date, and thousands more will be found as clinical and population sequencing efforts become increasingly widespread. The major mechanism of KV11.1 loss of function is misfolding and failure to traffic to the cell surface. Deep mutational scanning of KCNH2 trafficking is a scalable, high-throughput method that can help identify new loss of function variants and decipher the large number of KCNH2 variants being found in the population.

Download here

Back to Overview

We use cookies on our website. Some of them are essential for the operation of the site, while others help us to improve this site and the user experience (tracking cookies). You can decide for yourself whether you want to allow cookies or not. Please note that if you reject them, you may not be able to use all the functionalities of the site.