Abstract
Connexin37 (Cx37) is a gap junction protein involved in cell-to-cell communication in the vasculature and other tissues. Cx37 suppresses proliferation of vascular cells involved in tissue development and repair in vivo, as well as tumor cells. Global deletion of Cx37 in mice leads to enhanced vasculogenesis in development, as well as collateralgenesis and angiogenesis in response to injury, which together support improved tissue remodeling and recovery following ischemic injury. Here we report the 1H, 15N, and 13C resonance assignments for an important regulatory domain of Cx37, the carboxyl terminus (CT; C233-V333). The predicted secondary structure of the Cx37CT domain based on the chemical shifts is that of an intrinsically disordered protein. In the 1H–15N HSQC, N-terminal residues S254-Y259 displayed a second weaker peak and residues E261-Y266 had significant line broadening. These residues are flanked by prolines (P250, P258, P260, and P268), suggesting proline cis–trans isomerization. Overall, these assignments will be useful for identifying the binding sites for intra- and inter-molecular interactions that affect Cx37 channel activity.
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Acknowledgements
This work is funded by the United States Public Health Service Grants, GM072631, HL131712, CA036727, and GM103427. We would like to thank Ed Ezell, manager of the Nuclear Magnetic Resonance Laboratory at the University of Nebraska Medical Center, for his assistance with collection of the NMR data.
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Li, H., Spagnol, G., Pontifex, T.K. et al. Chemical shift assignments of the connexin37 carboxyl terminal domain. Biomol NMR Assign 11, 137–141 (2017). https://doi.org/10.1007/s12104-017-9735-x
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DOI: https://doi.org/10.1007/s12104-017-9735-x