Protein-protein interactions of KChIP proteins and Kv4.2.
To prove heteromeric assembly of KChIP proteins, the present study is carried out. The results of chemical crosslinking and pull down assay revealed that KChIP1, KChIP2.1, and KChIP2.2 could form homo- as well as hetero-oligomer, and this oligomerization exhibited a Ca(2+)-dependent manner. Moreover, homomeric and heteromeric assembly of KChIPs did not perturb their interaction with Kv4.2 K(+) channel, indicating that the region associated with oligomerization of KChIPs was distinct from that for binding with Kv4.2. Together with previous findings that the net effects of KChIP proteins on the molecular properties and trafficking of Kv channel were different, these observations open a fascinating possibility that the electrophysiological properties of Kv channel may be differently regulated by homomeric and heteromeric assembly of KChIPs.
Lin
Ya-Ling
YL
Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan, ROC.
Chen
Chia-Yi
CY
Cheng
Ching-Ping
CP
Chang
Long-Sen
LS
D002118:Calcium / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D002942:Circular Dichroism; D006801:Humans; D051605:Kv Channel-Interacting Proteins; D015221:Potassium Channels / Q000235:genetics / Q000378:metabolism*; D024642:Potassium Channels, Voltage-Gated; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D017433:Protein Structure, Secondary; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism*; D051672:Shal Potassium Channels
D002135:Calcium-Binding Proteins; C497018:KCND2 protein, human; C496750:KCNIP1 protein, human; C496752:KCNIP2 protein, human; D051605:Kv Channel-Interacting Proteins; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D021122:Protein Subunits; D051672:Shal Potassium Channels; D002118:Calcium