Figure 11.

Sequence and expression analysis of Has-Som. The Has-Som transcript encodes an ORF of 200 residues. A putative signal sequence (↑), two glycosylated Asp residues (highlighted black), and a polyadenylation signal (bold) are indicated. (B) Has-Som expression in 4 mm juveniles is restricted to the mantle. (C) Magnified view of the boxed region in B illustrates the expression of Has-Som in the outer fold of the mantle. (D) Expanded view of the boxed region in C reveals the morphology of Has-Som expressing cells with large vacuoles (arrows). (E) An alignment of Has-Som with deuterostome ependymin proteins illustrates the low level of sequence conservation. The four cysteine residues required for disulfide linkages in deuterostome taxa are indicated (*). Sequences are followed by the percentage of sites sharing identity and biochemical similarity. Positions shaded black indicate cases where more than 50% of the residues are identical, and grey where biochemical similarity is shared with the consensus residue. GenBank accession numbers are in brackets.