Tom Sandbox: Difference between revisions
From Proteopedia
Jump to navigationJump to search
No edit summary |
No edit summary |
||
| Line 19: | Line 19: | ||
GCN4 is said to have a heptad repeat, or seven unit repeated sequence. Here the heptad repeat is a leucine, every seven units. When the structure of the alpha helices is taken into account, it is clear that each leucine is being stacked on top of the last one, every seven units. This creates the zipper-like repeated projections from the two polypeptide chains. Below we see a pictorial representation of the sequence of amino acids as we look down the length of the coiled coil structure. | GCN4 is said to have a heptad repeat, or seven unit repeated sequence. Here the heptad repeat is a leucine, every seven units. When the structure of the alpha helices is taken into account, it is clear that each leucine is being stacked on top of the last one, every seven units. This creates the zipper-like repeated projections from the two polypeptide chains. Below we see a pictorial representation of the sequence of amino acids as we look down the length of the coiled coil structure. | ||
[[Image:Coiledcoil-wheelcartoon.gif|300px]] | [[Image:Coiledcoil-wheelcartoon.gif|center|300px]] | ||
'''Image 1:A pictorial representation of the heptad repeat. By following through the wheels alphabetically, it is clear how the leucines will stack every 7 units. The apostrophe denotes the other subunit.'''(from Kgutwin in Wikipedia Commons http://commons.wikimedia.org/wiki/File:Coiledcoil-wheelcartoon.gif) | '''Image 1:A pictorial representation of the heptad repeat. By following through the wheels alphabetically, it is clear how the leucines will stack every 7 units. The apostrophe denotes the other subunit.'''(from Kgutwin in Wikipedia Commons http://commons.wikimedia.org/wiki/File:Coiledcoil-wheelcartoon.gif) | ||
At every a and a' we have a Leucine, while at the d and d' locations we typically see valine. <ref name="Voet" /> | At every a and a' we have a Leucine, while at the d and d' locations we typically see valine. <ref name="Voet" /> | ||
===Binding=== | ===Binding=== | ||
