PDBsum entry 2jc2

Metal binding protein

PDB id: 2jc2

Contents

Protein chain

166 a.a. *

Ligands

SO4 ×6

Waters ×140

* Residue conservation analysis

PDB id:

2jc2

Name:

Metal binding protein

Title:

The crystal structure of the natural f112l human sorcin mutant

Structure:

Sorcin. Chain: a, b, c, d. Synonym: 22 kda protein, cp-22, v19, f112l human sorcin mutant. Engineered: yes. Mutation: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Organ: heart, muscle, brain and adrenal medulla. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

2.50Å R-factor: 0.254 R-free: 0.289

Authors:

S.Franceschini,A.Ilari,G.Colotti,E.Chiancone

Key ref:

S.Franceschini et al. (2008). Molecular basis for the impaired function of the natural F112L sorcin mutant: X-ray crystal structure, calcium affinity, and interaction with annexin VII and the ryanodine receptor. Faseb J, 22, 295-306. PubMed id: 17699613

Date:

19-Dec-06 Release date: 28-Aug-07

Protein chains

P30626  (SORCN_HUMAN) -  Sorcin from Homo sapiens

Seq: 198 a.a.

Struc: 166 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Faseb J 22:295-306 (2008)

PubMed id: 17699613

Molecular basis for the impaired function of the natural F112L sorcin mutant: X-ray crystal structure, calcium affinity, and interaction with annexin VII and the ryanodine receptor.

S.Franceschini, A.Ilari, D.Verzili, C.Zamparelli, A.Antaramian, A.Rueda, H.H.Valdivia, E.Chiancone, G.Colotti.

ABSTRACT

The penta-EF hand protein sorcin participates in the modulation of Ca2+-induced calcium-release in the heart through the interaction with several Ca2+ channels such as the ryanodine receptor. The modulating activity is impaired in the recently described natural F112L mutant. The F112 residue is located at the end of the D helix next to Asp113, one of the calcium ligands in the EF3 hand endowed with the highest affinity for the metal. The F112L-sorcin X-ray crystal structure at 2.5 A resolution displays marked alterations in the EF3 hand, where the hydrogen bonding network established by Phe112 is disrupted, and in the EF1 region, which is tilted in both monomers that give rise to the dimer, the stable form of the molecule. In turn, the observed tilt is indicative of an increased flexibility of the N-terminal part of the molecule. The structural alterations result in a 6-fold decrease in calcium affinity with respect to the wild-type protein and to an even larger impairment of the interaction with annexin VII and of the ability of sorcin to interact with and inhibit ryanodine receptors. These results provide a plausible structural and functional framework that helps elucidate the phenotypic alterations of mice overexpressing F112L-sorcin.