Fig. 5

Expression patterns of N. vectensis nicotinic acetylcholine receptor genes. NvnAChRαD was broadly expressed in the planula and tentacle bud stages, but then became restricted to the endodermal tips of the tentacles (A–D). NvnAChRαE expression begun during the planula stages and then became restricted to the tentacle buds at the tentacle bud stage. By the polyp stage, expression was restricted to a band in the tentacles (E–H). NvnAChRαG expression begun in the planula within the developing pharynx, and this pharyngeal expression was maintained into the juvenile polyp stage (I–L). NvnAChRαI expression started in a scattered salt and pepper pattern at the aboral end, then restricted to the developing pharynx in the planula and was maintained here in the juvenile polyp (M–P). NvnAChRαR expression started broadly within the gastrula, planula, and tentacle bud stages, and this broad expression was maintained in the endoderm of the juvenile polyps (Q–T). NvnAChRαV expression started at the late planula stage within the pharynx, and expression was maintained there in the juvenile polyps (U–X). NvnAChRαU expression started at the late planula/early tentacle bud stage in the developing pharynx, and was maintained there in the juvenile polyps (Y–AB). We did not observe any expression of NvnAChRαZ, despite RNA-sequencing data suggesting expression after 144hpf (AC–AF). Expression of NvnAChRαH started at the planula stage in the developing pharynx, and was maintained there in the juvenile polyps (AG–AJ). NvnAChRαJ and NvnAChRαK expression both started in the planula stages, continued being expressed into the tentacle bud stage at the apical tuft, and was lost by the juvenile polyp stage (AK–AR). NvnAChRαQ was first broadly expressed at the planula and tentacle bud stages, then became restricted to endodermal tentacle and aboral ectoderm (AS–AV). A scattered salt and pepper expression of NvnAChRαB was observed in the developing tentacles, and the tentacles of the juvenile polyps (AW–AZ). NvnAChRαC expression was observed at the planula stages as a scattered salt and pepper pattern in the endoderm until the juvenile polyp stage, when expression was restricted to the tentacle tips (BA–BD). NvnAChRαF was expressed at the late planula stages within a few cells of the developing tentacles; this expression became restricted to a cluster of cells at the basal end of the tentacles (BE–BH). Graphs at the end of each row consist of the temporal expression according to previously published RNA-seq. data [28]. Within the graphs, white = blastula, blue = gastrula, green = planula, red = late planula/tentacle bud, and yellow = juvenile polyp stages. All images have the oral end directed to the left