Leukotriene B4 receptor 1

Leukotriene B4 receptor 1

Leukotriene B4 receptor 1 (BLT1) is a G protein-coupled receptor (GPCR) that binds to leukotriene B4 (LTB4), a potent inflammatory mediator. This receptor plays a crucial role in the immune system by mediating the chemotactic response of leukocytes to sites of inflammation.

Structure

BLT1 is a member of the G protein-coupled receptor family, characterized by seven transmembrane domains. The receptor is encoded by the LTB4R gene located on chromosome 14 in humans. The structure of BLT1 allows it to interact with G proteins, which in turn activate various intracellular signaling pathways.

Function

The primary function of BLT1 is to mediate the effects of leukotriene B4, which include the recruitment and activation of neutrophils, eosinophils, and other immune cells to sites of inflammation. This receptor is involved in various inflammatory responses and is implicated in diseases such as asthma, rheumatoid arthritis, and atherosclerosis.

Expression

BLT1 is predominantly expressed in leukocytes, including neutrophils, monocytes, and macrophages. It is also found in other tissues such as the spleen and bone marrow.

Signaling Pathways

Upon binding to leukotriene B4, BLT1 activates G proteins, which then trigger downstream signaling pathways such as the phospholipase C pathway, leading to the production of inositol trisphosphate (IP3) and diacylglycerol (DAG). These molecules further propagate the signal, resulting in cellular responses like chemotaxis, degranulation, and the production of reactive oxygen species.

Clinical Significance

Due to its role in mediating inflammatory responses, BLT1 is a potential target for therapeutic intervention in various inflammatory diseases. Inhibitors of BLT1 are being investigated for their potential to treat conditions such as asthma, chronic obstructive pulmonary disease (COPD), and inflammatory bowel disease (IBD).

Related Receptors

BLT1 has a closely related receptor, Leukotriene B4 receptor 2 (BLT2), which also binds to leukotriene B4 but with lower affinity. BLT2 is involved in similar but distinct signaling pathways and has a broader tissue distribution compared to BLT1.

See Also

• Leukotriene B4
• G protein-coupled receptor
• Inflammation
• Neutrophil
• Asthma
• Rheumatoid arthritis
• Atherosclerosis