Membrane proteins are proteins that interact with biological membranes. They are one of the common types of protein along with soluble globular proteins, fibrous proteins, and disordered proteins.

They are targets of over 50% of all modern medicinal drugs.

It is estimated that 20–30% of all genes in most genomes encode membrane proteins.

Microglial membrane protein or receptor is the basis of mediating microglia to play the inflammatory role and they have been found to be upregulated by recognizing associated ligands or sensing changes in the nervous system microenvironment. They can then allosterically activate the downstream signal transduction and produce a series of complex cascade reactions that can activate microglia, promote microglia chemotaxis and stimulate the release of pro-inflammatory factors such as TNF-α, IL-β to effectively damage the nervous system and cause apoptosis of neurons ¹⁾.

Aquaporin 4 (AQP4) belongs to the aquaporin family of integral membrane proteins that conduct water through the cell membrane.