Alkaline phosphatase 1 (ALP1)

GPI-anchored alkaline phosphatase (ALP), specifically the ALP1 isoform, is a membrane-bound enzyme predominantly expressed in the midgut epithelium of mosquito larvae, such as Aedes aegypti (Fernandez et al., 2006; Jimenez et al., 2012). It functions physiologically in the hydrolysis of phosphate esters and the transport of nutrients across the midgut membrane (Stalinski et al., 2016). In the field of vector control, this protein is highly significant as a primary functional receptor for the Cry toxins produced by Bacillus thuringiensis subsp. israelensis (Bti), including Cry11Aa and Cry4Ba (Likitvivatanavong et al., 2011). The interaction between these toxins and ALP is a critical step in the toxins' mechanism of action, where binding triggers toxin oligomerization and the formation of lethal pores in the larval midgut cells (Fernandez et al., 2006; Jimenez et al., 2012). This process leads to the destruction of the gut lining and the eventual death of the mosquito larvae (Lee et al., 2014). Due to its essential role in toxin-mediated mortality, ALP is a major focus for developing biopesticides and monitoring insecticide resistance in mosquito populations (Stalinski et al., 2016).

Other names

GPI-anchored alkaline phosphataseMembrane-bound alkaline phosphatasemALPAae-mALPAlkaline phosphatase

Binding of Cry toxins to the receptor facilitates toxin oligomerization, membrane insertion, and pore formation in midgut epithelial cells, leading to cell lysis and larval death.