- The table shows selected species of all major lineages examined in this study and their tektin gene complement. Species are listed according to five groups indicated on the left: Unicellular organisms, nonbilaterians, spiralians, ecdysozoans, and deuterostomes. The tektin gene complement for each species is presented by total number of tektin genes within their genome in the right column, as well as the number of homologs for each of the four bilaterian classes: Tektin-2, Tektin-1, Tektin-4, and Tektin-3/5. Note that these four Tektin classes are bilaterian specific originating by ancient gene duplications from two nonbilaterian and one unicellular tektin gene(s). The number of tektin genes in species range from zero in placozoans up to ten in the leech and planarian, and demonstrate substantial gain and loss of tektin genes in various metazoan lineages. A complete table of all species included in this study, with the exception of some teleost fish with identical tektin complements, is shown in Additional file 1
