The crystal structure of TRPM2 MHR1/2 domain reveals a conserved Zn 2+ -binding domain essential for structural integrity and channel activity.
Sander, S., Pick, J., Gattkowski, E., Fliegert, R., Tidow, H.(2022) Protein Sci 31: e4320-e4320
- PubMed: 35634784 
- DOI: https://doi.org/10.1002/pro.4320
- Primary Citation of Related Structures:  
7AOV - PubMed Abstract: 
Transient receptor potential melastatin 2 (TRPM2) is a Ca 2+ -permeable, nonselective cation channel involved in diverse physiological processes such as immune response, apoptosis, and body temperature sensing. TRPM2 is activated by ADP-ribose (ADPR) and 2'-deoxy-ADPR in a Ca 2+ -dependent manner. While two distinct binding sites exist for ADPR that exert different functions dependent on the species, the involvement of either binding site regarding the superagonistic effect of 2'-deoxy-ADPR is not clear yet. Here, we report the crystal structure of the MHR1/2 domain of TRPM2 from zebrafish (Danio rerio), and show that both ligands bind to this domain and activate the channel. We identified a so far unrecognized Zn 2+ -binding domain that was not resolved in previous cryo-EM structures and that is conserved in most TRPM channels. In combination with patch clamp experiments we comprehensively characterize the effect of the Zn 2+ -binding domain on TRPM2 activation. Our results provide insight into a conserved motif essential for structural integrity and channel activity.
Organizational Affiliation: 
Hamburg Advanced Research Centre for Bioorganic Chemistry (HARBOR) & Department of Chemistry, Institute for Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany.