Fig. 6. Nv-muscle LIM. Phylogenetic analysis and gene expression. (A) Alignment of 62 amino acid residues from the conserved LIM domain. Conserved residues are indicated in red (Conserved Domain Database at NCBI: pfam00412.8, LIM). (B) Phylogeny of LIM sequences based on neighbor-joining analysis. The tree was constructed and labeled as in Fig. 3. Sequences included in the analysis are: CG4656-PA (hypothetical protein), Drosophila, residues 4-63; CG30174-PA (hypothetical protein), Drosophila, residues 93-152; CG30179-PA (hypothetical protein), Drosophila, residues 104-163; CRIP1 (cysteine-rich protein 1), Homo, residues 4-63; CSRP1 (cysteine and glycine-rich protein 1), Homo, residues 10-68; CSRP2 (smooth muscle LIM protein), Homo, residues 10-68; CSRP3 (cysteine and glycine-rich protein 3, cardiac LIM protein), Homo, residues 10-68; FHL1 (four and a half LIM domains 1), Homo, residues 101-160; limpet, Drosophila, residues 220-277; M-LIM (muscle LIM protein), Nematostella, residues 4-62; Mlp60A (muscle LIM protein at 60A), Drosophila, residues 11-69; Mlp84B (muscle LIM protein at 84B), Drosophila, residues 12-70. The tree is drawn as though rooted between the Limpet/CRIP clade and the muscle LIM/CSRP clade. (C-H) Expression of Nv-muscle LIM. (C,D) Expression begins at mid-late planula stages in the precursors of the eight endodermal mesenteries (arrows). (E) Mid level optical section of a late planula, indicating expression in the gastrodermal lining of the coelenteron. The endodermal mesenteries are not in the plane of focus. Note that the pharynx and outer epidermis do not express Nv-muscle LIM. (F-H) In early polyp stages, the highest expression is in the endodermal lining (arrows) of the developing tentacles (tn). (G,H) Lateral views. In F, the mouth is bent towards the viewer to reveal the tip of the developing tentacle (arrow). The asterisk indicates the site of the mouth.