 |
PDBsum entry 4hex
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Calcium binding protein
|
PDB id
|
|
|
|
4hex
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
A novel trans conformation of ligand-Free calmodulin.
|
|
|
Authors
|
|
V.Kumar,
V.P.Chichili,
X.Tang,
J.Sivaraman.
|
|
|
Ref.
|
|
Plos One, 2013,
8,
e54834.
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
Calmodulin (CaM) is a highly conserved eukaryotic protein that binds
specifically to more than 100 target proteins in response to calcium (Ca(2+))
signal. CaM adopts a considerable degree of structural plasticity to accomplish
this physiological role; however, the nature and extent of this plasticity
remain to be fully understood. Here, we report the crystal structure of a novel
trans conformation of ligand-free CaM where the relative disposition of two
lobes of CaM is different, a conformation to-date not reported. While no major
structural changes were observed in the independent N- and C-lobes as compared
with previously reported structures of Ca(2+)/CaM, the central helix was tilted
by ∼90° at Arg75. This is the first crystal structure of CaM to show a
drastic conformational change in the central helix, and reveals one of several
possible conformations of CaM to engage with its binding partner.
|
|
|
|
|
|
|
