"To determine whether there were any changes in 5-HT synthesis, we measured
tph-1 expression in N2 and
grk-2 mutants by generating transgenic strains expressing GFP using the
tph-1 promoter (
tph-1::GFP). No differences in
tph-1::GFP expression were observed in the N2 and
grk-2 mutant strains as assessed by fluorescence (data not shown). We also evaluated TPH-1 using a mammalian Tph1 antibody and found that TPH-1 protein levels are similar in wild type and
grk-2 mutants at several developmental stages (Fig. 4B)."