Establishment of a tagged variant of Lgr4 receptor suitable for functional and expression studies in the mouse

Area of Science:

• Molecular Biology
• Genetics
• Cell Biology

Background:

• Leucine-rich repeat-containing G-protein-coupled receptor 4 (LGR4) is crucial during development, with deficiency causing lethality.
• LGR4's primary known role involves potentiating Wnt signaling, but emerging evidence suggests involvement in other pathways.
• Studying LGR4's diverse signaling roles requires effective tools for its detection and analysis.

Purpose of the Study:

• To generate a genetically modified mouse model expressing a tagged LGR4 receptor.
• To create a tool for tracking LGR4 expression and analyzing its function in vivo.
• To facilitate the biochemical characterization and identification of LGR4 binding partners.

Main Methods:

• Gene targeting in mouse oocytes to create a Lgr4 allele fused with a triple hemagglutinin (3HA) tag.
• Utilizing the 3HA tag for surface labeling and isolation of LGR4-positive cells from mouse small intestinal crypts.
• Employing HA tag-specific antibodies for biochemical analysis of LGR4.

Main Results:

• A fully functional LGR4 receptor tagged with 3HA was successfully generated in mice.
• The 3HA tag enables tracking of LGR4 expression across various mouse tissues.
• LGR4-positive cells from small intestinal crypts can be isolated and analyzed using surface labeling.
• The HA tag facilitates biochemical characterization and potential identification of LGR4 binding partners.

Conclusions:

• The generated 3HA-tagged LGR4 mouse model is a valuable tool for studying LGR4 expression and signaling.
• This model allows for the isolation and analysis of specific LGR4-expressing cell populations.
• The tagged receptor provides a means to investigate LGR4's biochemical properties and interactions.