Neurotensin receptor 1 (NTSR1), a member of the Class A G protein-coupled receptor superfamily, plays an important role in modulating dopaminergic neuronal activity and eliciting opioid-independent analgesia. Recent studies suggest that promoting \{beta}-arrestin-biased signaling in NTSR1 may diminish drugs of abuse, such as psychostimulants, thereby offering a potential avenue for treating human addiction-related disorders. In this study, we utilized a novel computational and experimental approach that combined nudged elastic band-based molecular dynamics simulations, Markov state models, temporal communication network analysis, site-directed mutagenesis, and conformational biosensors, to explore the intricate mechanisms underlying NTSR1 activation and biased signaling. Our study reveals a dynamic stepwise transition mechanism and activated transmission network associated with NTSR1 activation. It also yields valuable insights into the complex interplay between the unique polar network, non-conserved ion locks, and aromatic clusters in NTSR1 signaling. Moreover, we identified a cryptic allosteric site located in the intracellular region of the receptor that exists in an intermediate state within the activation pathway. Collectively, these findings contribute to a more profound understanding of NTSR1 activation and biased signaling at the atomic level, thereby providing a potential strategy for the development of NTSR1 allosteric modulators in the realm of G protein-coupled receptor biology, biophysics, and medicine.

本研究针对脑神经肽受体1(NTSR1)的激活及其偏向性信号这一问题进行了探讨，填补了现有研究的空白。通过创新的计算与实验结合方法，揭示了NTSR1激活过程中的动态过渡机制及其信号传递网络，识别了一个隐秘的别构位点，这些发现有助于深入理解NTSR1激活及其在药物开发中的潜在应用。

Deciphering the unique dynamic activation pathway in a G protein-coupled
  receptor enables unveiling biased signaling and identifying cryptic
  allosteric sites in conformational intermediates

解密G蛋白偶联受体中的独特动态激活途径揭示偏向性信号和隐秘别构位点