The
flr-2::SL2::gfp::
h2b reporter allele is expressed in five pharyngeal neuron classes (I4, I5, M1, M4, and M5). A notable feature of the extrapharyngeal expression of the
flr-2 reporter allele is expression in the AVL and DVB neurons, the only extrapharyngeal neurons of the C. elegans nervous system that innervate gut tissue (not the foregut, but the midgut; White et al., 1986).