Extended Data Fig. 8: Ontogenetic expression profiling of trochozoan larva-related genes and their spatial expression in early developmental stages of scallop.

(a–d) Expression levels of caveolin, innexin and ATP1B genes in four trochozoans P. yessoensis, U. unicinctus, H. discus hannai and C. gigas. In comparison. ATP1B shows stronger early-expression over caveolin/innexin during early developmental stages. (e) Left panel: whole mount in situ hybridization of caveolin, innexin and ATP1B genes in early developmental stages of scallop. The major expression sites of caveolin and innexin genes were largely correspond to the regions with forthcoming larval characteristic features whereas the expression of ATP1B largely corresponds to the forthcoming adult territory (sfi /sf). No signal in the control group using sense probes confirmed the reliability of observed positive signals. Right panel: the scanning electron microscopy (SEM) micrograph of the trochophora larva of scallop P. yessoensis. sfi, shell field invagination; at, apical tuft; pt, prototroch; sf, shell field; cf, ciliated field.