Peusis toxin acts by all of the following mechanisms except ?
Ans. is 'c' i.e., Increased calcium release from saroplasmic reticulum Peusis toxin . Peussis toxin is an exotoxin that has A and B subunits. . B subunit binds to the target cells whereas A subunit acts on the target. . First, the peussis toxin itself gets activated by glutathione and ATP. . Once the toxin gets activated it activates cell membrane bound G proteins. . Peussis toxin catalyzes the ADP ribosylation of the G proteins and activates them. . The activated G protein in turn activates adenylate cyclase, this results in an outpouring of cAMP which activates protein kinase and other intracellular messangers.
ADP ribosylation of proteins associated with receptors
Increase cyclic AMP
Increased calcium release from sarcoplasmic reticulum
Acts through G alpha subunit