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Neuromedin U receptors (NMURs), including NMUR1 and NMUR2, are a group of Gq/11-coupled G protein-coupled receptors (GPCRs). NMUR1 and NMUR2 play distinct, pleiotropic physiological functions in peripheral tissues and in the central nervous system (CNS), respectively, according to their distinct tissue distributions. These receptors are stimulated by two endogenous neuropeptides, neuromedin U and S (NMU and NMS) with similar binding affinities. NMURs have gathered attention as potential drug targets for obesity and inflammatory disorders. Specifically, selective agonists for NMUR2 in peripheral tissue show promising long-term anti-obesity effects with fewer CNS-related side effects. However, the mechanisms of peptide binding specificity and receptor activation remain elusive. Here, we report four cryo-electron microscopy structures of Gq chimera-coupled NMUR1 and NMUR2 in complexes with NMU and NMS. These structures reveal the conserved overall peptide-binding mode and the mechanism of peptide selectivity for specific NMURs, as well as the common activation mechanism of the NMUR subfamily. Together, these findings provide insights into the molecular basis of the peptide recognition and offer an opportunity for the design of the selective drugs targeting NMURs.

Motilin is an endogenous peptide hormone almost exclusively expressed in the human gastrointestinal (GI) tract. It activates the motilin receptor (MTLR), a class A G protein–coupled receptor (GPCR), and stimulates GI motility. To our knowledge, MTLR is the first GPCR reported to be activated by macrolide antibiotics, such as erythromycin. It has attracted extensive attention as a potential drug target for GI disorders. We report two structures of G q -coupled human MTLR bound to motilin and erythromycin. Our structures reveal the recognition mechanism of both ligands and explain the specificity of motilin and ghrelin, a related gut peptide hormone, for their respective receptors. These structures also provide the basis for understanding the different recognition modes of erythromycin by MTLR and ribosome. These findings provide a framework for understanding the physiological regulation of MTLR and guiding drug design targeting MTLR for the treatment of GI motility disorders.

Taking the leaves of five Machilus species as a research object, they are Machilus oreophila, Machilus chinensis, Machilus microcarpa, Machilus lichuanensis and Machilus suaveolens. By measuring leaf surface area, cell length and width , the total dust retention, pH value of retention fluid and the content of Pb, Cr, Fe, Cu and Cd of metallic elements were measured, and compare the dust retention of five plant seedling leaves ability. The results showed that: the leaves of different kinds of Machilus have different dust abilities. Comprehensive analysis can be obtained from five kinds of Machilus dust ability in descending order of M. suaveolens > M. lichuanensis > M. chinensis > M. microcarpa > M. oreophila.   ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 4, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

Migraine headache has become global pandemics and is the number one reason of work day loss. The most common drugs for anti-migraine are the triptan class of drugs that are agonists for serotonin receptors 5-HT1B and 5-HT1D. However, these drugs have side effects related to vasoconstriction that could have fatal consequences of ischemic heart disease and myocardial infarction. Lasmiditan is a new generation of anti-migraine drug that selectively binds to the serotonin receptor 5-HT1F due to its advantage over the tripan class of anti-migraine drugs. Here we report the cryo-EM structure of the 5-HT1F in complex with Lasmiditan and the inhibitory G protein heterotrimer. The structure reveals the mechanism of 5-HT1F-selective activation by Lasmiditan and provides a template for rational design of anti-migraine drugs.

Neuromedin U receptors (NMURs), including NMUR1 and NMUR2, are a group of Gq/11-coupled G protein-coupled receptors (GPCRs) related to pleiotropic physiological functions. Upon stimulation by two endogenous neuropeptides, neuromedin U and S (NMU and NMS) with similar binding affinities, NMUR1 and NMUR2 primarily display distinct peripheral tissue and central nervous system (CNS) functions, respectively, due to their distinct tissue distributions. These NMU receptors have triggered extensive attention as drug targets for obesity and immune inflammation. Specifically, selective agonists for NMUR1 in peripheral tissue show promising long-term anti-obesity effects with fewer CNS-related side effects. However, the mechanisms of peptide binding specificity and receptor activation remain elusive due to the lack of NMU receptor structures, which hamper drug design targeting NMU receptors. Here, we report four cryo-electron microscopy structures of Gq chimera-coupled NMUR1 and NMUR2 bound with NMU and NMS. These structures present the conserved overall peptide-binding mode and reveal the mechanism of peptide selectivity for specific NMURs, as well as the common activation mechanism of the NMUR subfamily. Together, these findings provide insights into the molecular basis of the peptide recognition selectivity and offer a new opportunity for designing selective drugs targeting NMURs.

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