GrlJ, a Dictyostelium GABAB-like receptor with roles in post-aggregation development
Yogikala Prabhu1, Rolf Müller, Christophe Anjard
1Institute of Biochemistry I, Centre for Biochemistry, Medical Faculty, University of Cologne, Köln, Germany. prabhuyo@mail.nih.gov <prabhuyo@mail.nih.gov>
BMC Developmental Biology
|May 16, 2007
Summary
The G-protein-coupled receptor GrlJ negatively regulates Dictyostelium discoideum development. Its inactivation causes accelerated development, affecting slug morphology and spore viability, indicating GrlJ
Area of Science:
- Cellular and Molecular Biology
- Developmental Biology
- Biochemistry
Background:
- G-protein-coupled receptors (GPCRs) are crucial cell surface receptors involved in signal transduction.
- Dictyostelium discoideum possesses diverse GPCR families, including Family 3 receptors, analogous to mammalian GABAB/glutamate receptors.
- GrlJ is identified as a novel Family 3 GPCR in D. discoideum.
Purpose of the Study:
- To investigate the function of GrlJ, a Family 3 GPCR, during Dictyostelium discoideum development.
- To characterize the developmental phenotype of a grlJ- mutant.
Main Methods:
- Gene knockout to create a grlJ- mutant strain.
- Green Fluorescent Protein (GFP) tagging to track GrlJ localization.
- Phenotypic analysis of mutant development, including slug formation and spore differentiation.
- Complementation of the mutant phenotype by expressing GFP-tagged GrlJ.
Main Results:
- GFP-tagged GrlJ localizes to the plasma membrane and internal membranes.
- Inactivation of grlJ results in precocious development, with mutants completing development approximately 6 hours earlier.
- grlJ- mutants exhibit altered slug morphology, including increased length and fragmentation, and produce malformed, less viable spores.
- Expression of full-length GFP-tagged GrlJ rescues the observed developmental defects.
Conclusions:
- GrlJ plays a significant role in regulating multiple stages of Dictyostelium development.
- GrlJ functions as a negative regulator of Dictyostelium development.
- GrlJ is essential for normal slug morphology and spore formation/viability.
More Related Videos
Related Concept Videos
01:15G Protein-coupled Receptors
G Protein-Coupled Receptors or GPCRs are membrane-bound receptors that transiently associate with heterotrimeric G proteins and induce an appropriate response to sensory stimuli such as light, odors, hormones, cytokines, or neurotransmitters.
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...
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...
01:15G Protein-coupled Receptors
G Protein-Coupled Receptors or GPCRs are membrane-bound receptors that transiently associate with heterotrimeric G proteins and induce an appropriate response to sensory stimuli such as light, odors, hormones, cytokines, or neurotransmitters.
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...
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...
01:22Activation and Inactivation of G Proteins
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...
01:21G-protein Coupled Receptors
G-protein coupled receptors are ligand binding receptors that indirectly affect changes in the cell. The actual receptor is a single polypeptide that transverses the cell membrane seven times creating intracellular and extracellular loops. The extracellular loops create a ligand specific pocket which binds to neurotransmitters or hormones. The intracellular loops holds onto the G-protein.
01:21G-protein Coupled Receptors
G-protein coupled receptors are ligand binding receptors that indirectly affect changes in the cell. The actual receptor is a single polypeptide that transverses the cell membrane seven times creating intracellular and extracellular loops. The extracellular loops create a ligand specific pocket which binds to neurotransmitters or hormones. The intracellular loops holds onto the G-protein.
01:24Small GTPases - Ras and Rho
Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
Three regulatory proteins control their activity: