Targeting motifs in frustule-associated proteins from the centric diatom .

The frustule of diatoms has an exceptional structure composed of inorganic and organic molecules. In the organic fraction, protein families were identified whose members are expected to have a complex cellular targeting to their final location within the frustule. Here we investigated for frustule-targeting signals two representatives of the cingulin family, the proteins CinY2 and CinW2; beside an already known, classical signal peptide, we have identified further regions involved in cellular targeting.