Fig. 3.

Phylogenetic tree of selected vertebrate and invertebrate ferritins. Unrooted tree of ferritin amino acid sequences reconstructed using the Neighbor Joining (NJ) method based on alignment using ClustalX. Alignment and sequence descriptions are provided as supporting information. The Ixodes ricinus FER1 clusters together with intracellular ferritins of different origin. The tick FER2 is closely related to plasma ferritins from the horseshoe crab and form a separate branch with other secreted ferritins from invertebrates. Arrows indicate ferritins of I. ricnius. Asterisk shows a presence of the iron responsive element (IRE) in the 5′- untranslated region of mRNA. Numbers at branches represent bootstrap support using NJ/minimal evolution criterion with 1,000 replicates each. (Bar: 0.1 substitutions per site.)