D2 and D3 dopamine receptor cell surface localization mediated by interaction with protein 4.1N.
We identified protein 4.1N as a D2-like dopamine receptor-interacting protein in a yeast two-hybrid screen. Protein 4.1N is a neuronally enriched member of the 4.1 family of cytoskeletal proteins, which also includes protein 4.1R of erythrocytes and the 4.1G and 4.1B isoforms. The interaction of protein 4.1N was specific for the D2 and D3 dopamine receptors and was independently confirmed in pulldown and coimmunoprecipitation assays. Deletion mapping localized the site of dopamine receptor/protein 4.1N interaction to the N-terminal segment of the third intracellular domain of D2 and D3 receptors and the carboxyl-terminal domain of protein 4.1N. D2 and D3 receptors were also found to interact with the highly conserved carboxyl-terminal domain of proteins 4.1R, 4.1G, and 4.1B. Immunofluorescence studies show that protein 4.1N and D2 and D3 dopamine receptors are expressed at the plasma membrane of transfected human embryonic kidney 293 and mouse neuroblastoma Neuro2A cells. However, expression of D2 or D3 receptors with a protein 4.1N truncation fragment reduces the level of D2 and D3 receptor expression at the plasma membrane. These results suggest that protein 4.1N/dopamine receptor interaction is required for localization or stability of dopamine receptors at the neuronal plasma membrane.
IBIOS Graduate Program in Molecular Medicine, Pennsylvania State College of Medicine, Hershey, Pennsylvania 17033, USA.
Alicia V
AV
Binda
Nadine
N
Kabbani
Ridwan
R
Lin
Robert
R
Levenson
D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D003285:Contractile Proteins / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D064448:Filamins; D006801:Humans; D008565:Membrane Proteins; D008840:Microfilament Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000378:metabolism*; D011485:Protein Binding; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D050637:Receptors, Dopamine D3; D017386:Sequence Homology, Amino Acid; D014162:Transfection
D003285:Contractile Proteins; D003598:Cytoskeletal Proteins; C493593:DRD3 protein, human; D064448:Filamins; D008565:Membrane Proteins; D008840:Microfilament Proteins; D009479:Neuropeptides; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; C120557:erythrocyte membrane protein band 4.1-like 1