Characterization of cell lines stably expressing human normal or mutated EGFP-tagged MC4R.
Blondet. Antonine A; Doghman. Mabrouka M; Rached. Mohamed M; Durand. Philippe P; Bégeot. Martine M; Naville. Danielle D
Key Findings
- A stable HEK‑293 cell line expressing fluorescently tagged human MC4‑R was generated.
- The normal receptor reaches the cell surface and reacts to hormones like the natural version, while mutated versions stay inside the cell and work poorly.
- NDP‑α‑MSH triggers the receptor to be pulled into the cell, an effect partly blocked by AgRP.
Practical Outcomes
- The study provides a research tool for scientists to study MC4‑R behavior, but it offers no actionable dosing, safety, or performance guidance for biohackers or self‑experimenters.
Summary
Scientists created a lab cell line that glows when it makes the MC4‑R protein, which helps control appetite. This lets them watch how the normal and mutated receptors move inside cells, but it doesn’t give any direct advice for people to use the peptide.
Abstract
The melanocortin receptor type 4 (MC4-R) is involved in food intake and represents a potential target for the treatment of some forms of obesity. The fluorescent protein EGFP was fused to the wild-type or mutated coding sequence of the human MC4-R. After transfection in HEK 293, clones stably expressing hMC4-R-EGFP were selected. Wild-type chimeric hMC4-R was well addressed to the cell membrane as demonstrated using confocal microscopy and displayed the same pharmacological characteristics as native hMC4R. NDP-alpha MSH induced a time-dependent internalization of MC4-R that was partially prevented by AgRP. The two mutated chimeric receptors studied here (CTCT-deleted and C271A) showed a high alteration of their response to ligand and were retained inside the cells. In conclusion, we have developed a model of clones stably expressing EGFP-tagged-hMC4-R. This is the only such model available to date and it provides a useful tool to follow the trafficking of MC4-R inside living cells.
Study Information
pubmed
2004
10.1093/jb/mvh064