Language
Country/Area
No result found
FPR1, FPR2 and FPR3: What's the mysterious story behind these three receptors?
In the human body, the formal peptide receptor (FPR) is a type of G protein-coupled receptor that is closely related to chemotaxis and plays a key role in the response of the immune system. The discovery of this receptor dates back to the 1970s, when researchers first explored how a small N-formyl methionine-related peptide reacted with human white blood cells. These receptors are not only involved in immune cell responses to infection but may also suppress the immune system under certain conditions. There are three main subtypes of formal peptide receptors, FPR1, FPR2 and FPR3, each with their own unique functions and properties.
Formyl peptide receptors were first identified based on their ability to bind N-formyl small peptides, which are often products of degradation by bacteria and host cells.
The journey of discovery
In 1970, scientists discovered a series of oligopeptides high in N-formyl methionine that could effectively stimulate neutrophils in rabbits and humans. In a series of experiments, these small peptides were shown to be able to guide cells to migrate in a directional pattern. The scientific community has begun to speculate that these small peptides are not only signaling molecules in immune responses, but their receptors are also key components in recognizing these signals.
For example, one of the most famous compounds of this type - N-formyl methionine-leucine-phenylalanine, or fMLF for short, is particularly effective in activating immune cells.
Structure and function
FPR is a receptor with seven hydrophobic transmembrane domains, and the configuration of these domains is affected by various factors. Studies have shown that multiple interactions are formed between the amino acid residues of these receptors, which are critical to the stability of their structures. In particular, the interaction between positively charged residues such as Arg84 and Arg205 and negatively charged phosphates contributes to the structure and function of the receptor.
Signal transmission pathway
When FPR is activated, it will trigger a series of intracellular changes, including the reorganization of the cytoskeleton, promoting cell migration and increasing the synthesis of chemical factors. The signaling pathway of FPR involves a variety of key biochemical reactions, especially G protein-dependent phospholipase C activation.
Ultimately, these signals lead to a sustained rise in intracellular calcium ion concentration, which is critical for the directional movement of cells.
FPR’s multiple roles
The function of FPR goes beyond this, and its dual role in the inflammatory response is eye-catching. FPR1 and FPR2 dominate the initiation of inflammatory response, while FPR3 plays a key role in the suppression and mediation of inflammation. Scientists have found that differences in these three receptors may lead to differences in an individual's ability to face infection and inflammation, and even affect susceptibility to certain neurological diseases.
Conclusion
With in-depth research on FPR, scientists are increasingly aware of its indispensable role in the immune system. The multiple functions of these receptors are intertwined with their structural properties, revealing more complex regulatory networks. How do different subtypes of these receptors influence the script of the immune response?
