2AMI

Solution Structure Of The Calcium-loaded N-Terminal Sensor Domain Of Centrin

Summary for 2AMI

• Entry DOI: 10.2210/pdb2ami/pdb
• NMR Information: BMRB: 6820
• Descriptor: Caltractin (1 entity in total)
• Functional Keywords: four-helix bundle, calcium sensor, ef-hand calcium binding protein, calmodulin, centrin, cell cycle
• Biological source: Chlamydomonas reinhardtii
• Total number of polymer chains: 1
• Total formula weight: 10817.40

Authors

Hu, H.T.,Fagan, P.A.,Bunick, C.G.,Sheehan, J.H.,Chazin, W.J. (deposition date: 2005-08-09, release date: 2005-08-23, Last modification date: 2024-05-01)

Primary citation

Sheehan, J.H.,Bunick, C.G.,Hu, H.,Fagan, P.A.,Meyn, S.M.,Chazin, W.J.
Structure of the N-terminal calcium sensor domain of centrin reveals the biochemical basis for domain-specific function.
J.Biol.Chem., 281:2876-2881, 2006

PubMed Abstract: Centrin is an essential component of microtubule-organizing centers in organisms ranging from algae and yeast to humans. It is an EF-hand calcium-binding protein with homology to calmodulin but distinct calcium binding properties. In a previously proposed model, the C-terminal domain of centrin serves as a constitutive anchor to target proteins, and the N-terminal domain serves as the sensor of calcium signals. The three-dimensional structure of the N-terminal domain of Chlamydomonas rheinhardtii centrin has been determined in the presence of calcium by solution NMR spectroscopy. The domain is found to occupy an open conformation typical of EF-hand calcium sensors. Comparison of the N- and C-terminal domains of centrin reveals a structural and biochemical basis for the domain specificity of interactions with its cellular targets and the distinct nature of centrin relative to other EF-hand proteins. An NMR titration of the centrin N-terminal domain with a fragment of the known centrin target Sfi1 reveals binding of the peptide to a discrete site on the protein, which supports the proposal that the N-terminal domain serves as a calcium sensor in centrin.

PubMed: 16317001
DOI: 10.1074/jbc.M509886200

Experimental method

SOLUTION NMR