No abstract

Detailed experimental evidence is presented in supporting the previous report of the authors on the direct observation of d‐holes and Cu−Cu bonding in Cu2O (see figure). It is shown that the accuracy of X‐ray measurements of charge density is limited by the extinction effect, and that theoretical calculations of charge transfer are limited by the approximations made and the models used.

Sensing and responding to temperature is crucial in biology. The TRPV1 ion channel is a well-studied heat-sensing receptor that is also activated by vanilloid compounds including capsaicin. Despite significant interest, the molecular underpinnings of thermosensing have remained elusive. The TRPV1 S1-S4 membrane domain couples chemical ligand binding to the pore domain during channel gating.However, the role of the S1-S4 domain in thermosensing is unclear. Evaluation of the isolated human TRPV1 S1-S4 domain by solution NMR, Far-UV CD, and intrinsic fluorescence shows that this domain undergoes a non-denaturing temperature-dependent transition with a high thermosensitivity. Further NMR characterization of the temperature-dependent conformational changes suggests the contribution of the S1-S4 domain to thermosensing shares features with known coupling mechanisms between this domain with ligand and pH activation. Taken together, this study shows that the TRPV1 S1-S4 domain contributes to TRPV1 temperature-dependent activation.

Mit detaillierten experimentellen Argumenten wird der frühere Bericht der Autoren über die direkte Beobachtung von d‐Löchern und einer Cu‐Cu‐Bindung in Cu2O (siehe Bild) gestützt. Sie legen dar, dass die Genauigkeit der Ladungsdichtebestimmung bei der Verwendung von Röntgen‐Strahlen durch den Auslöschungseffekt und bei theoretischen Rechnungen durch die gemachten Annahmen und die verwendeten Modelle begrenzt wird.