Fig 3. Evolution in the cis-regulatory elements necessary for lin-3 expression in C. elegans.

Distribution of cis-regulatory elements (the regulatory triplet) in different species. 300 bp upstream of the ATG of the vulval isoform of lin-3 are shown (and up to 2 kb for C. sp. 1, where no upstream ATG is found). Orange depicts the E-box and purple the NHR site. “>” or “<” show orientation of the regulatory site.