Two closely related endocytic proteins that share a common OCRL-binding motif with APPL1.
Mutations of the inositol 5' phosphatase oculocerebrorenal syndrome of Lowe (OCRL) give rise to the congenital X-linked disorders oculocerebrorenal syndrome of Lowe and Dent disease, two conditions giving rise to abnormal kidney proximal tubule reabsorption, and additional nervous system and ocular defects in the case of Lowe syndrome. Here, we identify two closely related endocytic proteins, Ses1 and Ses2, which interact with the ASH-RhoGAP-like (ASPM-SPD-2-Hydin homology and Rho-GTPase Activating Domain-like) domain of OCRL. The interaction is mediated by a short amino acid motif similar to that used by the rab-5 effector APPL1 (Adaptor Protein containing pleckstrin homology [PH] domain, PTB domain and Leucine zipper motif 1) APPL1 for OCRL binding. Ses binding is mutually exclusive with APPL1 binding, and is disrupted by the same missense mutations in the ASH-RhoGAP-like domain that also disrupt APPL1 binding. Like APPL1, Ses1 and -2 are localized on endosomes but reside on different endosomal subpopulations. These findings define a consensus motif (which we have called a phenylalanine and histidine [F&H] motif) for OCRL binding and are consistent with a scenario in which Lowe syndrome and Dent disease result from perturbations at multiple sites within the endocytic pathway.
Department of Cell Biology, Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT, USA.
Laura E
LE
Swan
Livia
L
Tomasini
Michelle
M
Pirruccello
Joël
J
Lunardi
Pietro
P
De Camilli
D048868:Adaptor Proteins, Signal Transducing; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000378:metabolism*; D017124:Conserved Sequence; D004705:Endocytosis; D011992:Endosomes / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D009800:Oculocerebrorenal Syndrome / Q000235:genetics / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism*
C464801:APPL1 protein, human; D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; C548332:PHETA1 protein, human; C548333:PHETA2 protein, human; D033921:Vesicular Transport Proteins; D010744:Phosphoric Monoester Hydrolases; C075695:OCRL protein, human