Self-assembly of the isolated KCNQ2 subunit interaction domain.
Mutations in the KCNQ2 gene cause myokymia and neonatal epilepsy, indicating that this K(+) channel regulates the excitability of lower motoneurons and CNS neurons. Little is known about the parameters that direct the assembly of this multimeric molecule and other KCNQ subunits. Here, we show that the carboxy-terminal subunit interaction domain of KCNQ2 autonomously folds and assembles into tetramers. This domain contains a bipartite coiled-coil motif. Whereas structural integrity of the second coiled-coil motif is crucial for tetramer formation, that of the first motif is less important. These data suggest a crucial role of coiled-coil motifs in tetrameric KCNQ channel assembly.
Wehling
Christina
C
Institute of Biochemistry, Christian-Albrechts-University Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany.
Beimgraben
Christian
C
Gelhaus
Christoph
C
Friedrich
Thomas
T
Saftig
Paul
P
Grötzinger
Joachim
J
Schwake
Michael
M
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D006801:Humans; D051658:KCNQ2 Potassium Channel / Q000737:chemistry* / Q000235:genetics; D008969:Molecular Sequence Data; D017510:Protein Folding; D017434:Protein Structure, Tertiary / Q000235:genetics
D051658:KCNQ2 Potassium Channel