Membrane bound<unk>  (mACE2) is a zinc-containing metalloenzyme located on the surface of intestinal enterocytes, renal tubular cells and other cells. mACE2 protein contains an N-terminal peptidase M2 domain and a C-terminal collectrin renal amino acid transporter domain. mACE2 is a single-pass type I membrane protein, with its<unk> tically active domain exposed on the surface of cells in the intestines and other tissues. The extracellular domain of mACE2 can be cleaved from the transmembrane domain by another<unk>  known as ADAM17 a member of the sheddase<unk>  family, during the protective phase of RAAS, the Renin<unk> n Aldosterone System which regulates our body's blood pressure. The resulting cleaved protein is known as soluble<unk>  or sACE2. It is released into the bloodstream where one of sACE2's functions is to turn excess<unk>  II into<unk>  1-7 which binds to MasR receptors creating localized vasodilation and hence decreasing blood pressure. Excess sACE2 may ultimately be excreted in the urine. Location within the human body == mACE2 is attached to the cell membrane of mainly enterocytes of the small intestine and duodenum, proximal tubular cells of the kidneys, glandular cells of the gallbladder, as well as Sertoli cells and Leydig cells of the testis. The expression profile of mACE2 in the human body was recently thoroughly evaluated by the Human Protein Atlas team using a large-scale multiomics approach combining several different methods for analysis of gene expression, including a stringent immunohistochemical analysis using two independent antibodies. mACE2 expression was in addition to the above-mentioned tissues, also seen in endothelial cells and pericytes of blood vessels within certain tissues, cardiomyocytes in heart tissue, and a smaller subset of cells within the thyroid gland, epididymis, seminal vesicle, pancreas, liver and placenta. Despite the fact that the respiratory system is the primary route of SARS-CoV-2 infection, very limited expression is seen, both at protein and mRNA level. The expression within the respiratory system is mainly restricted to the upper bronchial and nasal epithelia, especially in the ciliated cells.
Angiotensin-converting enzyme 2
Prostaglandin-endoperoxide synthase 2
Haptocorrin
Calcitonin gene-related peptide
Indoleamine 2,3-dioxygenase
Immunoevasin
Tetanospasmin
Beta-secretase 1