Figure 7.
Figure 7: Two architectures for ion-channel proteins. a, The
antiparallel architecture of ClC Cl- channels contains
structurally similar halves with opposite orientations in the
membrane (arrows). This architecture permits like ends (same
dipole sense) of -helices
to point at the membrane centre from opposite sides of the
membrane (180° separation). b, The parallel or barrel stave
architecture of K+ channels contains structurally similar or
identical subunits with the same membrane orientation (arrows).
Helices point at the membrane centre from the same side of the
membrane. Helices are depicted as dipoles with blue (positive)
and red (negative) ends.
The above figure is reprinted
by permission from Macmillan Publishers Ltd:
Nature
(2002,
415,
287-294)
copyright 2002.
-helices
to point at the membrane centre from opposite sides of the
membrane (180° separation). b, The parallel or barrel stave
architecture of K+ channels contains structurally similar or
identical subunits with the same membrane orientation (arrows).
Helices point at the membrane centre from the same side of the
membrane. Helices are depicted as dipoles with blue (positive)
and red (negative) ends.