Extended Data Fig. 1: Optimization of the trans-Tango ligand.
From: Transsynaptic labeling and transcriptional control of zebrafish neural circuits
Six different ligand constructs were injected along with plasmids encoding the trans-Tango receptor, arrestin–TEV and Tol2 transposase RNA into single-cell zebrafish embryos, the progeny of Tg(QUAS:mApple-CAAX) and the Tg(ptf1a:Gal4-VP16) driver line that promotes strong expression of Tg(UAS:GFP) in the hindbrain. a–f, Ligands containing the transmembrane domain of zebrafish nrxn1a and varying lengths of mouse ICAM. a,a′, 10xUAS-E1B:sGCG-nrxn1a produced consistent trans-Tango labeling in the hindbrain (n = 20/25) but also nonspecific labeling (b; n = 15/25). c,c′, 10xUAS-E1B:sGCG-ICAM(1235)-nrxn1a produced consistent hindbrain labeling (n = 17/25) and nonspecific labeling (d; n = 11/25). e,e′, 10xUAS-E1B:sGCG-ICAM-nrxn1a produced fewer trans-Tango-labeled larvae (n = 6/25) and nonspecific labeling (f; n = 5/25). g–l, Ligands containing the transmembrane domain of zebrafish nrxn1b and varying lengths of mouse ICAM. g,g′, 10xUAS-E1B:sGCG-nrxn1b produced consistent trans-Tango labeling (n = 15/25) and substantial nonspecific labeling (h; n = 12/25). i,i′, 10xUAS-E1B:sGCG-ICAM(1235)-nrxn1b produced consistent labeling in the hindbrain (n = 23/25) and minimal nonspecific labeling (j; n = 2/25). k,k′, 10xUAS-E1B:sGCG-ICAM-nrxn1b produced trans-Tango labeling (n = 21/25) and nonspecific labeling (l; n = 14/25). Scale bars, 50 μm. Images are representative of trans-Tango labeling in the indicated number of larvae in five independent experiments for each ligand construct.
