TY - JOUR
T1 - Chemical shift assignments of the connexin45 carboxyl terminal domain
T2 - Monomer and dimer conformations
AU - Kopanic, Jennifer L.
AU - Sorgen, Paul L.
N1 - Funding Information:
Acknowledgments This work is funded by the United States Public Health Sevice Grant, GM072631. Jennifer Kopanic is funded by the Graduate Assistance in Areas of National Need (GAANN) Fellowship. We would like to thank and acknowledge Ed Ezell manager of the Nuclear Magnetic Resonance Laboratory Manager at the University of Nebraska Medical Center for his assistance with DOSY analysis and Dr. Fabien Kieken for his invaluable NMR expertise.
PY - 2013/10
Y1 - 2013/10
N2 - Connexin45 (Cx45) is a gap junction protein involved in cell-to-cell communication in the heart and other tissues. Here we report the 1H, 15N, and 13C resonance assignments for the monomer and dimer conformations of the Cx45 carboxyl terminal (Cx45CT) domain and provide evidence of dimerization using diffusion ordered spectroscopy. The predicted secondary structure of the Cx45CT domain based on the chemical shifts identified one region of α-helical structure, which corresponds to the residues that broadened beyond detection in the dimer confirmation. Previous biophysical studies from our laboratory characterizing the CT domain from the other major cardiac connexins, Cx40 and Cx43, suggest that the amount of α-helical content may translate into the ability of a protein to dimerize. Even though the CT domain is thought to be the main regulatory domain of most connexins, the physiological role of CT dimerization is currently unknown. Therefore, these assignments will be useful for determining the intermolecular interactions that mediate Cx45CT dimerization, information that will be used to characterize dimerization in functional channels, as well as characterizing the binding sites for molecular partners involved in Cx45 regulation.
AB - Connexin45 (Cx45) is a gap junction protein involved in cell-to-cell communication in the heart and other tissues. Here we report the 1H, 15N, and 13C resonance assignments for the monomer and dimer conformations of the Cx45 carboxyl terminal (Cx45CT) domain and provide evidence of dimerization using diffusion ordered spectroscopy. The predicted secondary structure of the Cx45CT domain based on the chemical shifts identified one region of α-helical structure, which corresponds to the residues that broadened beyond detection in the dimer confirmation. Previous biophysical studies from our laboratory characterizing the CT domain from the other major cardiac connexins, Cx40 and Cx43, suggest that the amount of α-helical content may translate into the ability of a protein to dimerize. Even though the CT domain is thought to be the main regulatory domain of most connexins, the physiological role of CT dimerization is currently unknown. Therefore, these assignments will be useful for determining the intermolecular interactions that mediate Cx45CT dimerization, information that will be used to characterize dimerization in functional channels, as well as characterizing the binding sites for molecular partners involved in Cx45 regulation.
KW - Carboxyl terminus
KW - Cx45
KW - Dimerization
KW - Gap junction
KW - Intrinsically disordered protein
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U2 - 10.1007/s12104-012-9431-9
DO - 10.1007/s12104-012-9431-9
M3 - Article
C2 - 23070843
AN - SCOPUS:84883488024
SN - 1874-2718
VL - 7
SP - 293
EP - 297
JO - Biomolecular NMR Assignments
JF - Biomolecular NMR Assignments
IS - 2
ER -