Figure 2.

Roles of Rab5 in the internalization of receptors and signaling pathways. The receptors are sorted through the early endosome. The GTP-Rab5 recruits GEF Rabex5, which stabilizes Rab5, and Vps34 regenerates phosphatidylinositol 3-phosphate. Most of the receptor enter into the late endosomes and then degrade after reaching the lysosomes, and some recycle to the cell membrane via Rab4 and Rab11. Rab5 involves numerous signaling pathways, which may influence the cell progress and disease development (see the text for further details).