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1m39
From Proteopedia
Solution structure of the C-terminal fragment (F86-I165) of the human centrin 2 in calcium saturated form
Overview
Human centrin 2 (HsCen2) is an EF-hand protein that plays a critical role in the centrosome duplication and separation during cell division. We studied the structural and Ca(2+)-binding properties of two C-terminal fragments of this protein: SC-HsCen2 (T94-Y172), covering two EF-hands, and LC-HsCen2 (M84-Y172), having 10 additional residues. Both fragments are highly disordered in the apo state but become better structured (although not conformationally homogeneous) in the presence of Ca(2+) and depending on the nature of the cations (K(+) or Na(+)) in the buffer. Only the longer C-terminal domain, in the Ca(2+)-saturated state and in the presence of Na(+) ions, was amenable to structure determination by nuclear magnetic resonance. The solution structure of LC-HsCen2 reveals an open two EF-hand structure, similar to the conformation of related Ca(2+)-saturated regulatory domains. Unexpectedly, the N-terminal helix segment (F86-T94) lies over the exposed hydrophobic cavity. This unusual intramolecular interaction increases considerably the Ca(2+) affinity and constitutes a useful model for the target binding.
About this Structure
1M39 is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
C-terminal half of human centrin 2 behaves like a regulatory EF-hand domain., Matei E, Miron S, Blouquit Y, Duchambon P, Durussel I, Cox JA, Craescu CT, Biochemistry. 2003 Feb 18;42(6):1439-50. PMID:12578356 Page seeded by OCA on Sat May 3 00:34:50 2008
