Chinese scholar NSMB published a paper: Molecular mechanism of selective recognition of kinin and activation of bradykinin receptor

On September 9, 2021, Jiang Yi/Xu Huaqiang's team from Shanghai Institute of Materia Medica, Chinese Academy of Sciences and Wang Mingwei's team published a study titled "Molecular basis for kinin selectivity and activation of the human bradykinin receptors" on Nature Structural & Molecular Biology .
Achievements, the first report of two types of kinins, Des-Arg ¹⁰ -kallidin and Bradykinin (Bradykinin), respectively, combined with two subtypes of bradykinin receptors B1R and B2R near-atomic resolution structure, revealing kinin selection The molecular mechanism of sexual recognition and its receptor activation
.

Kinin and its receptor are an important part of the Kallikrein-kinin system (Kallikrein-kinin system, KKS)
.

Bradykinin receptors belong to the A family of G protein-coupled receptors, including two subtypes, B1R and B2R

Although the amino acid sequence of each active kinin in the KKS system is similar, different kinins have obvious selectivity for B1R and B2R (Figure 1a)
.

For example, Bradykinin is more than 10,000 times more selective for B2R than B1R, while Des-Arg ^10- kallidin is more than 100,000 times more selective for B1R than B2R

In this study, the researchers used cryo-electron microscopy to analyze the three-dimensional structure of B1R and B2R that bind Des-Arg ^10- kallidin, bradykinin, and downstream G _q protein complexes, with a resolution of 3.
0 and 2.
9 angstroms (Figure 1b and 1c)
.

Combining the results of structural analysis and functional experiments, the research team revealed the molecular mechanism of selective recognition of bradykinin receptor subtypes by kinin (Figure 1d-f)

The cryo-electron microscopy data in this study were collected on the cryo-electron microscopy platform of Shanghai Institute of Medicine and Mizuki Future (Beijing) cryo-electron microscopy platform
.

Yin Yuling, a 2016 PhD student at Shanghai Institute of Materia Medica, and Ye Chenyu, a 2019 PhD student at Fudan University, are the co-first authors of the paper

Original link: https://　

Figure 1.
The cryo-EM structure of the complex of bradykinin receptors B1R and B2R and selective kinin
.

a, Pattern diagram of selective recognition of bradykinin receptors by kinin; b, Des-Arg ¹⁰ -kallidin-B1R-G _q complex structure; c, Bradykinin-B2R-G _q complex structure; d, Des -Arg ¹⁰ -The structural basis of kallidin-B1R-Gq for B1R selectivity; e, the structural basis for Bradykinin's selectivity to B2R; f, the mechanism model of kinin selective recognition of bradykinin receptors

　　(Contribution department: Xu Huaqiang's research group)