Presenilins interact with Rab11, a small GTPase involved in the regulation of vesicular transport.

Presenilin 1 (PS1) mutations account for the majority of early-onset dominant cases of familial Alzheimer's disease. Presenilins (PSs) are located in many intra-cellular compartments such as the endoplasmic reticulum, Golgi apparatus, nuclear region and vesicular structures. These proteins include from seven to nine putative transmembrane domains, with the N- and C-terminal ends and a large hydrophilic loop orientated towards the cytoplasm. We report an interaction between the human PS1 or PS2 hydrophilic loop and Rab11, a small GTPase belonging to the Ras-related superfamily. Interaction domains were mapped to codons 374-400 for PS1 and to codons 106-179 for Rab11, a region including the fourth GTP-binding domain. Considering the implication of Rab proteins in vesicular transport pathways, the PS-Rab11 inter-action suggests that PSs might be involved in amyloid precursor protein vesicular routing.