Roles of protein kinase C and actin-binding protein 280 in the regulation of intracellular trafficking of dopamine D3 receptor.

Published

Journal Article

D(3) dopamine receptor (D(3)R) is expressed mainly in parts of the brain that control the emotional behaviors. It is believed that the improper regulation of D(3)R is involved in the etiology of schizophrenia. Desensitization of D(3)R is weakly associated with G protein-coupled receptor kinase (GRK)/beta-arrestin-directed internalization. This suggests that there might be an alternative pathway that regulates D(3)R signaling. This report shows that D(3)R undergoes robust protein kinase C (PKC)-dependent sequestration that is accompanied by receptor phosphorylation and the desensitization of signaling. PKC-dependent D(3)R sequestration, which was enhanced by PKC-beta or -delta, was dynamin dependent but independent of GRK, beta-arrestin, or caveolin 1. Site-directed mutagenesis of all possible phosphorylation sites within the intracellular loops of D(3)R identified serine residues at positions 229 and 257 as the critical amino acids responsible for phorbol-12-myristate-13-acetate (PMA)-induced D(3)R phosphorylation, sequestration, and desensitization. In addition, the LxxY endocytosis motif, which is located between residues 252 and 255, was found to play accommodating roles for PMA-induced D(3)R sequestration. A continuous interaction with the actin-binding protein 280 (filamin A), which was previously known to interact with D(3)R, is required for PMA-induced D(3)R sequestration. In conclusion, the PKC-dependent but GRK-/beta-arrestin-independent phosphorylation of D(3)R is the main pathway responsible for the sequestration and desensitization of D(3)R. Filamin A is essential for both the efficient signaling and sequestration of D(3)R.

Full Text

Duke Authors

Cited Authors

  • Cho, E-Y; Cho, D-I; Park, JH; Kurose, H; Caron, MG; Kim, K-M

Published Date

  • September 2007

Published In

Volume / Issue

  • 21 / 9

Start / End Page

  • 2242 - 2254

PubMed ID

  • 17536008

Pubmed Central ID

  • 17536008

International Standard Serial Number (ISSN)

  • 0888-8809

Digital Object Identifier (DOI)

  • 10.1210/me.2007-0202

Language

  • eng

Conference Location

  • United States