PUBLICATIONS

Chercher par auteur :
Tous les AuteursAlcaraz GAmendola JAnkri NAziz AAzzaz FBaudot PBialowas ABoudkkazi SBoumedine NBrechet ACaillard OCampanac ECarlier EChahinian HCoq JOCudmore RHDaoudal GDe San Feliciano MDebanne DDebreux KDenis DDesplantes RDi Giovanni JDubruc FDufour MDuménieu MDéglise PEl Far OExtrémet JFantini JFormisano-Treziny CFronzaroli-Molinieres LFékété AGabert JGasselin CGastrein PGiraud PGoaillard JMHaddjeri-Hopkins AIborra CIncontro SInglebert YLEVEQUE CLopez CLévêque CMarcaggi PMarqueze BMarra VMaulet YMoubarak EMoutot NRama SRamirez-Franco JJRussier MSammari MSangiardi MSeagar MSourdet VTapia MTell FTemporal SUsseglio FWakade AWoodhouse AYahi NYoussouf FZanin EZbili M

Chercher par année de publication :
Toutes les Années2023202220212020201920182017201620152014201320122011201020092008200720062005200420032002200120001999199819971996199519941993199219911990198919881987198619841983198219811980197919781974

Chercher par mot-clé :

	PUBLICATIONS
ACCUEIL   |  PUBLICATIONS

ANNEE : 2001

Interactions of calmodulin with two peptides derived from the c-terminal cytoplasmic domain of the Ca(v)1.2 Ca2+ channel provide evidence for a molecular switch involved in Ca2+-induced inactivation.

AUTEURS : Mouton J, Feltz A, Maulet Y.

REVUE : J Biol Chem
N° Pubmed : 11294864
When opened by depolarization, L-type calcium channels are rapidly inactivated by the elevation of Ca(2+) concentration on the cytoplasmic side. Recent studies have shown that the interaction of calmodulin with the proximal part of the cytoplasmic C-terminal tail of the channel plays a prominent role in this modulation. Two motifs interacting with calmodulin in a Ca(2+)-dependent manner have been described: the IQ sequence and more recently the neighboring CB sequence. Here, using synthetic peptides and fusion proteins derived from the Ca(v)1.2 channel combined with biochemical techniques, we show that these two peptides are the only motifs of the cytoplasmic tail susceptible to interact with calmodulin. We determined the K(d) of the CB interaction with calmodulin to be 12 nm, i.e. below the K(d) of IQ-calmodulin, thereby precluding a competitive displacement of CB by IQ in the presence of Ca(2+). In place, we demonstrated that a ternary complex is formed at high Ca(2+) concentration, provided that calmodulin and the peptides are initially allowed to interact at a low Ca(2+) concentration. These results provide evidence that CB and IQ motifs interacting together with calmodulin constitute a minimal molecular switch leading to Ca(2+)-induced inactivation. In addition, we suggest that they could also be the tethering site of calmodulin.