Postsynaptic targeting of MAGUKs mediated by distinct N-terminal domains.
Postsynaptic targeting of PSD-95 has been extensively studied; however, little is known about how other MAGUKs are localized. Proper targeting of PSD-95 requires dual palmitoylation of an N-terminal motif. We now find that the N-termini of closely related PSD-93 and SAP-102 are also involved in postsynaptic targeting. PSD-93 is N-terminally palmitoylated; however, unlike PSD-95, palmitoylation does not explain the necessity of the N-terminus for PSD-93 postsynaptic targeting. Furthermore, when the N-terminus of PSD-95 is replaced with the first 30 or 64, but not the first 10, amino acids of PSD-93, the chimera is targeted to postsynaptic sites independent of palmitoylation. Similarly, when the N-terminus of PSD-95 is replaced with the non-palmitoylated N-terminus of SAP-102, postsynaptic targeting is maintained. These results suggest that MAGUKs contain diverse signals within their N-termini for postsynaptic targeting.
Firestein
B L
BL
Department of Physiology, University of California at San Francisco, 94143-0444, USA.
Craven
S E
SE
Bredt
D S
DS
D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D000076122:Disks Large Homolog 4 Protein; D004622:Embryo, Mammalian; D051528:Guanylate Kinases; D006624:Hippocampus / Q000166:cytology / Q000502:physiology; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000378:metabolism*; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D009479:Neuropeptides / Q000737:chemistry / Q000378:metabolism*; D009703:Nucleoside-Phosphate Kinase / Q000378:metabolism*; D019308:Palmitic Acid / Q000378:metabolism; D051381:Rats; D011994:Recombinant Proteins / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013569:Synapses / Q000502:physiology* / Q000648:ultrastructure; D014162:Transfection; D025521:Tumor Suppressor Proteins
D000076122:Disks Large Homolog 4 Protein; C101195:Dlg3 protein, rat; C501449:Dlg4 protein, rat; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C501451:Mpp2 protein, rat; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D011994:Recombinant Proteins; D025521:Tumor Suppressor Proteins; C033652:postsynaptic density proteins; D019308:Palmitic Acid; D009703:Nucleoside-Phosphate Kinase; C496468:DLG2 protein, human; D051528:Guanylate Kinases