title: Confinement Alters the Structure and Function of Calmodulin.
abstract: Many cellular reactions involving proteins, including their biosynthesis, misfolding, and transport, occur in confined compartments. Despite its importance, a structural basis of understanding of how confined environments alter protein function is still lacking. Herein, we explore structure-function correlations of calmodulin (CaM), a multidomain protein involved in many calcium-mediated signaling pathways, in reverse micelles. Confinement dramatically alters CaM structure and function. The protein forms an extended structure in bulk water, but becomes compacted in reverse micelles. In addition, confinement changes the function of CaM. Specifically, the protein binds the MLCK, AcN19, and somatostatin peptides in dilute buffer, but binds only the MLCK and AcN19 peptides in reverse micelles. In summary, we determined a new CaM structure in reverse micelles and demonstrate that confinement can modulate both protein structure and function.
authors.affiliation: Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Collaborative Innovation Center of Chemistry for Life Sciences, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P.R. China.
authors.forename: Guohua
authors.initials: G
authors.lastname: Xu
authors.affiliation: Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Collaborative Innovation Center of Chemistry for Life Sciences, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P.R. China.|Graduate University of Chinese Academy of Sciences, Beijing, 100029, P.R. China.
authors.forename: Kai
authors.initials: K
authors.lastname: Cheng
authors.affiliation: Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Collaborative Innovation Center of Chemistry for Life Sciences, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P.R. China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Wu
authors.affiliation: Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Collaborative Innovation Center of Chemistry for Life Sciences, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P.R. China.
authors.forename: Maili
authors.initials: M
authors.lastname: Liu
authors.affiliation: Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Collaborative Innovation Center of Chemistry for Life Sciences, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P.R. China.
authors.forename: Conggang
authors.identifier: 0000-0002-5798-1722
authors.initials: C
authors.lastname: Li
mesh_terms: D002147:Calmodulin / Q000737:chemistry* / Q000378:metabolism*; D008823:Micelles; D008958:Models, Molecular; D011487:Protein Conformation
chemical_list: D002147:Calmodulin; D008823:Micelles
keywords: NMR spectroscopy; calmodulin; confinement; protein structures; reverse micelles