WAP, Follistatin, Immunoglobulin, Kunitz and NTR Domain-Containing (WFIKKN) genes encoding proteins with domain architectures typical of vertebrate WFIKKN proteins are present in the genomes of B. belcheri, B. floridae and A. lucayanum. (A) Proteins 328450_PRF0 and 328460_PRF0 of B. belcheri correspond to different regions of the WFIKKN protein of B. belcheri and the WFIKKN protein of B. floridae (XP_002607185.1). The transcriptome of A. lucayanum contains three transcripts (GESY01012772.1, GESY01032162.1, and GESY01032163.1) of the WFIKKN gene and the genome assembly of A. lucayanum contains a single scaffold encoding the 5′ part half of the WFIKKN gene (LZCU01164105.1); (B) Analysis of the transcriptome and genome of A. lucayanum with FixPred has provided evidence that its WFIKKN gene encodes a protein (WFIKKN_ASYLU) with the same domain architecture as those of B. belcheri (WFIKKN_BRABE) and B. floridae (WFIKKN_BRAFL). The figure illustrates the Pfam domain organizations of the proteins and the position of protein fragments of WFIKKN proteins. Color code for Pfam-A domains: WAP—green; Kazal—red; Immunoglobulin—blue; Kunitz—yellow; netrin (NTR)—purple.