ce-HisCl1 is a negative selection marker. HisCl1 is a D. melanogaster inhibitory histamine-gated chloride channel Ce-HisCl1. ce-HisCl1 was optimized for expression in C. elegans by including two early introns (from ama-1
), which has been shown to increase gene expression (Aljohani et al., 2020). We also minimized the ribosomal binding site energy but did not codon-optimize the ce-HisCl1 transgene. ce-HisCl1 was generated by gene synthesis (TwistBiosciences, CA, USA) in a [1-2] Gateway Entry vector.