8JMI

The cryo-EM structure of insect gustatory receptor Gr64a from Drosophila melanogaster in complex with maltose

Summary for 8JMI

• Entry DOI: 10.2210/pdb8jmi/pdb
• EMDB information: 36422
• Related PRD ID: PRD_900018
• Descriptor: Gustatory receptor for sugar taste 64a, alpha-D-glucopyranose-(1-4)-beta-D-glucopyranose (2 entities in total)
• Functional Keywords: gustatory receptor, gr64a, maltose, ligand-gated ion channel, membrane protein
• Biological source: Drosophila melanogaster (fruit fly)
• Total number of polymer chains: 4
• Total formula weight: 220042.19

Authors

Ma, D.,Guo, J. (deposition date: 2023-06-04, release date: 2024-02-07, Last modification date: 2024-03-06)

Primary citation

Ma, D.,Hu, M.,Yang, X.,Liu, Q.,Ye, F.,Cai, W.,Wang, Y.,Xu, X.,Chang, S.,Wang, R.,Yang, W.,Ye, S.,Su, N.,Fan, M.,Xu, H.,Guo, J.
Structural basis for sugar perception by Drosophila gustatory receptors.
Science, 383:eadj2609-eadj2609, 2024

PubMed Abstract: Insects rely on a family of seven transmembrane proteins called gustatory receptors (GRs) to encode different taste modalities, such as sweet and bitter. We report structures of sweet taste receptors GR43a and GR64a in the apo and sugar-bound states. Both GRs form tetrameric sugar-gated cation channels composed of one central pore domain (PD) and four peripheral ligand-binding domains (LBDs). Whereas GR43a is specifically activated by the monosaccharide fructose that binds to a narrow pocket in LBDs, disaccharides sucrose and maltose selectively activate GR64a by binding to a larger and flatter pocket in LBDs. Sugar binding to LBDs induces local conformational changes, which are subsequently transferred to the PD to cause channel opening. Our studies reveal a structural basis for sugar recognition and activation of GRs.

PubMed: 38305684
DOI: 10.1126/science.adj2609

Experimental method

ELECTRON MICROSCOPY (2.6 Å)