Figure 4

Sequence and expression analysis of Has-ferrt. (A) Has-ferrt shares significant similarity with members of the ferritin family. Iron binding motifs are indicated by *. 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. (B). Expression of Has-ferrt within trochophore larvae is located to the shell field (sf) and prototroch (arrow). (C) Pre-torsional veligers express Has-ferrt in operculum forming cells of the foot (f), the prototroch (p) and mantle (m). Cells expressing Has-ferrt intensely within foot primordia cells immediately adjacent to the mantle where operculum formation takes place are indicated by a white arrow. (D) Has-ferrt expression within 1 mm juveniles is located within the mantle (m). (E) A magnified view of the boxed region in D reveals Has-ferrt expression restricted to the outer fold (yellow bracket), the anterior edge of the outer fold (arrowhead) and diffusely within the inner fold (black arrow).