Related Experiment Video
Updated: Aug 9, 2025

Detection of G Protein-coupled Receptor Expression in Mouse Vagal Afferent Neurons using Multiplex In Situ Hybridization
Published on: September 20, 2021
Genome-Wide Identification of G Protein-Coupled Receptors in Ciliated Eukaryotes
Shuai Luo1, Peng Zhang1, Wei Miao1
1Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
Abstract:
G protein-coupled receptors (GPCRs) are the largest family of transmembrane receptors and play important roles in many physiological processes. As a representative group of protozoa, ciliates represent the highest stage of eukaryotic cell differentiation and evolution in terms of their reproductive mode, two-state karyotype, and extremely diverse cytogenesis patterns. GPCRs have been poorly reported in ciliates. In this study, we identified 492 GPCRs in 24 ciliates. Using the existing classification system for animals, GPCRs in ciliates can be assigned to four families, including families A, B, E, and F. Most (377 members) belong to family A. The number of GPCRs is extremely different in different ciliates; the Heterotrichea ciliates usually have more GPCRs than other ciliates. Parasitic or symbiotic ciliates usually have only a few GPCRs. Gene/genome duplication events seem to play important roles in the expansion of the GPCR superfamily in ciliates. GPCRs in ciliates displayed seven typical domain organizations. GPCRs in an ortholog group are common and conserved in all ciliates. The gene expression analysis of the members in this conserved ortholog group in the model ciliate, Tetrahymena thermophila, suggested that these GPCRs play important roles in the life cycle of ciliates. In summary, this study provides the first comprehensive genome-wide identification of GPCRs in ciliates, improving our understanding of the evolution and function of GPCR in ciliates.
Related Concept Videos
G Protein-coupled Receptors
GPCRs are also called heptahelical, 7TM, or serpentine receptors, and consist of seven (H1-H7) transmembrane alpha-helices that span the bilayer to form a cylindrical core. The transmembrane helices are connected by three extracellular loops and three...
Transducer Mechanism: G Protein–Coupled Receptors
GPCRs are also called heptahelical,...
G-protein Coupled Receptors
Activation and Inactivation of G Proteins
G-Protein Gated Ion Channels
Sensory...
GPCRs Regulate Adenylyl Cylase Activity

