Impact of Fluorophore and Epitope Position on Destabilized Reporter Performance in <i>C. elegans</i>

promoter reporter did not detectably oscillate. We systematically dissected this transgene, finding that placement of a 3xFLAG tag adjacent to a PEST sequence severely hampered oscillatory expression of a mNeonGreen promoter reporter. Surprisingly, reporter designs that effectively oscillate with a GFP or mNeonGreen fluorophore fail to oscillate when mStayGold is used, with these reporters remaining detectable over 24 hours following promoter inactivation. In addition, other tested epitopes (Myc, ALFA, OLLAS) did not hamper PEST-dependent destabilization but led to varying levels of reporter expression. This study details key considerations for designing destabilized fluorescent promoter reporters.