Pertussis toxin that encode Ptl proteins. Together, these proteins form the PT secretion complex. PT is released from "B. pertussis" in an inactive form. Following PT binding to a cell membrane receptor, it is taken up in an endosome, after which it undergoes retrograde transport to the trans-Golgi network and endoplasmic reticulum. At some point during this transport, the A subunit (or protomer) becomes activated, perhaps through the action of glutathione and ATP. PT catalyzes the ADP-ribosylation of the α subunits of the heterotrimeric G protein. This prevents the G proteins from interacting with G protein-coupled receptors on the cell membrane, thus
Ménétrier's disease Ménétrier's disease Ménétrier disease (also known as hypoproteinemic hypertrophic gastropathy; named after a French physician Pierre Eugène Ménétrier, 1859–1935), is a rare, acquired, premalignant disease of the stomach characterized by massive gastric folds, excessive mucous production with resultant protein loss, and little or no acid production. The disorder is associated with excessive secretion of transforming growth factor alpha (TGF-α). Individuals with the disease present with upper abdominal pain (epigastric), at times accompanied by nausea, vomiting, loss of appetite, edema, weakness, and weight loss. A small amount of gastrointestinal bleeding may occur, which is typically due to superficial mucosal erosions; large