a Fluorescence micrographs of transgenic endu-2(tm4977);byEx1814[endu-2P::endu-2::EGFP::endu-23′UTR] animals. ENDU-2::EGFP is detected in the intestine, the somatic gonad, coelomocytes, and extracellular space between the uterus and embryos. N = 5 independent experiments. b Fusion of the 1–19 amino acids of ENDU-2 (SSendu-2) to neuronal-specific expressed EGFP is sufficient for secretion of EGFP protein. Upper panels show localization of unc-119P::EGFP which is detected only in neuronal cells (strong) of animals and embryos. Lower panels are images showing localization of unc-119P::SSendu-2::EGFP which is detected in the neurons (weak), coelomocytes and interspace between egg shell and embryos, indicative of efficient secretion of EGFP mediated by the secretion signal peptide of ENDU-2. Images are representative for more than 20 animals, analyzed by using a ×40 objective. c Fluorescence micrographs of GFP-antibody staining of endu-2(tm4977);byEx1375[endu-2P::endu-2::EGFP], endu-2(tm4977);byEx1449[endu-2P::Δssendu-2::EGFP] and endu-2(tm4977);byEx1875[endu-2P::SSsel-1::Δssendu-2::EGFP] transgenic animals at 20 °C. ENDU-2::EGFP (n = 62, 100%) and SSsel-1::ΔssENDU-2::EGFP (n = 21, 100%) but not ΔssENDU-2::EGFP (n = 26, 0%) is detected in the germline. N = 2 independent replicates. d smFISH staining reveals presence of endu-2 mRNA in the intestine (white arrow), but not in the germline. Blue: DAPI stained nuclear DNA. Red: smFISH probes stained mRNA. N = 4. Scale bar 10 µm for all images in this Figure.