Figure 2.

Repertoire of Wnt subfamilies in arthropods, an onychophoran and a lophotrochozoan. Grey boxes indicate putatively lost Wnt subfamilies. Question marks indicate Wnts that have not been found but cannot be defined as ‘missing’ because assigned genomes have not been sequenced or annotated. Duplicated Wnts are represented by overlapping boxes. Square brackets indicate that spider WntA was isolated from another spider, C. salei. E, embryonic expression patterns are available; e, embryonic expression has been studied but specific expression patterns could not be detected; F, functional data are available. Note that for T. castaneum all Wnts have been knocked down by means of RNAi, but phenotypes could only be detected for wg/Wnt1 and Wnt8/D. Wnt3 is present in deuterostomes and cnidarians, but has been lost in the lineage leading to the protostomes.