Probable gustatory receptor which mediates acceptance or avoidance behavior, depending on its substrates. Expressed in neurons of the dorsal pharyngeal sense organs of larvae. Belongs to the insect chemoreceptor superfamily. Gustatory receptor (GR) family. Gr22e subfamily. The strain (Berkeley) sequenced by the collaborative genome project contains a deletion of T nucleotide in position 49 leading to premature stop codon. It is therefore considered a pseudogene.