Two distinct calcium‐calmodulin interactions with N‐terminal regions of the olfactory and rod cyclic nucleotide‐gated channels characterized by NMR spectroscopy

FEBS Letters

Andreotti, Giuseppina³  Contessa, Gian Marco⁴  Orsale, Maria⁴  Motta, Andrea³  Melino, Sonia⁴  Desideri, Alessandro²  Torre, Vincent¹  Cicero, Daniel O⁴  Paci, Maurizio⁴ 

[1] INFM and SISSA, Settore di Biofisica, Trieste, Italy;INFM, University of Rome ‘Tor Vergata’, via della Ricerca Scientifica, 00133 Rome, Italy;Istituto di Chimica Biomolecolare del CNR, Pozzuoli, University of Naples, Naples, Italy;Department of Chemical Sciences and Technologies, University of Rome ‘Tor Vergata’, via della Ricerca Scientifica, 00133 Rome, Italy

关键词: Cyclic nucleotide-gated channel;    Calmodulin modulation;    Protein–protein interaction;    Molecular recognition;    Nuclear magnetic resonance;   

DOI  :  10.1016/S0014-5793(03)00716-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The interactions of calcium-calmodulin with two fragments of the N-terminal domains of the olfactory α-subunit and rod β-subunit cyclic nucleotide-gated channels have been investigated using nuclear magnetic resonance spectroscopy. The results indicate that in the two cases both the N-terminal and the C-terminal calmodulin lobes are involved in the interaction. The olfactory cyclic nucleotide-gated channel segment forms a 1:1 complex with calmodulin, whereas the rod fragment forms a 2:1 complex. The correlation times of the two complexes, as estimated by ¹⁵N relaxation studies, are compatible with the observed stoichiometries. These results indicate differences in the mode of action by which calmodulin modulates the activity of both channels, and suggest either that the rod channel is modulated through a simultaneous interaction of two β-subunits with calmodulin or that other regions of the N-terminus are necessarily implicated in the binding.

【 授权许可】

Unknown