alpha cell-inducible Arx knockout harboring a Cre-recombinase-sensitive floxed Arx allele; a cell lineage tracing system for reporting on the effects of Arx inactivation on alpha cell fate. In alphaiAKO islets, Dox exposure stimulates Cre recombinase expression specifically in Gcg+ alpha cells. Cre then inactivates the floxed Arx allele and activates YFP transgene expression from the Rosa26 locus. (see related strains: alphaiDKO and alphaiADKO)