Photoreceptor synaptic protein HRG4 (UNC119) interacts with ARL2 via a putative conserved domain

Proc. Natl. Acad. Sci. U.S.A.

Doan

et al. 2007

160

184

The mouse Pde6d gene encodes a ubiquitous prenyl binding protein, termed PrBP/␦, of largely unknown physiological function. PrBP/␦ was originally identified as a putative rod cGMP phosphodiesterase (PDE6) subunit in the retina, where it is relatively abundant. To investigate the consequences of Pde6d deletion in retina, we generated a Pde6d ؊/؊ mouse by targeted recombination. Although manifesting reduced body weight, the Pde6d ؊/؊ mouse was viable and fertile and its retina developed normally. Immunocytochemistry showed that farnesylated rhodopsin kinase (GRK1) and prenylated rod PDE6 catalytic subunits partially mislocalized in Pde6d ؊/؊ rods, whereas rhodopsin was unaffected. In Pde6d ؊/؊ rod single-cell recordings, sensitivity to single photons was increased and saturating flash responses were prolonged. Pde6d ؊/؊ scotopic paired-flash electroretinograms indicated a delay in recovery of the dark state, likely due to reduced levels of GRK1 in rod outer segments. In Pde6d ؊/؊ cone outer segments, GRK1 and cone PDE6␣ were present at very low levels and the photopic b-wave amplitudes were reduced by 70%. Thus the absence of PrBP/␦ in retina impairs transport of prenylated proteins, particularly GRK1 and cone PDE, to rod and cone outer segments, resulting in altered photoreceptor physiology and a phenotype of a slowly progressing rod/cone dystrophy.prenyl binding protein ͉ rod/cone dystrophy ͉ vesicular transport ͉ isoprenylation ͉ membrane association

Section: Discussionmentioning

confidence: 99%

Deletion of PrBP/δ impedes transport of GRK1 and PDE6 catalytic subunits to photoreceptor outer segments

Proc. Natl. Acad. Sci. U.S.A.

Doan

et al. 2007

160

184

Journal of Biological Chemistry

“…Cilia function was identified first in the protozoon Leishmania donovani (30). Experiments in ciliated hTert-RPE and IMCD3 cells (31), pulldowns (32)(33)(34), and crystallography (35)(36)(37)(38) identified Arf-like (ARL) proteins ARL2 and ARL3 as interactants of PDE␦ and UNC119 (31,38,39). ARL3 localizes to the photoreceptor synaptic terminal, cell body, inner segment, and connecting cilium (40) and colocalizes with RP2 (retinitis pigmentosa protein 2) (41), UNC119 (42), and PDE␦ (22).…”

Section: Mice Lipidated Phototransduction Proteins Showed Traffickinmentioning

confidence: 99%

Arf-like Protein 3 (ARL3) Regulates Protein Trafficking and Ciliogenesis in Mouse Photoreceptors

Hanke-Gogokhia

Gerstner

et al. 2016

112

“…Full-length bovine GRK1 consists of 561 amino acid residues with a predicted mass of 63 kDa. To verify spec- ificity of the interaction between the C termini of GRK1 and PDE␦, the two independent GRK1 clones (encoding the 165 and 69 amino acid residues of the GRK1 C terminus, respectively) were co-transformed into yeast with bovine RG4/Unc-119, a retina-dominant protein that shares 23% identity with PDE␦ in its C-terminal 153 amino acids (29,30). We found that partial GRK1 polypeptides encoded by these two clones only interacted with PDE␦ but not with RG4/Unc-119, suggesting that PDE␦ specifically interacts with GRK1.…”

Section: Pde␦ Is Expressed In Rods Andmentioning

confidence: 99%

Photoreceptor cGMP Phosphodiesterase δ Subunit (PDEδ) Functions as a Prenyl-binding Protein

Liu

Journal of Biological Chemistry

et al. 2004

126

122

Bovine PDE␦ was originally copurified with rod cGMP phosphodiesterase (PDE) and shown to interact with prenylated, carboxymethylated C-terminal Cys residues. Other studies showed that PDE␦ can interact with several small GTPases including Rab13, Ras, Rap, and Rho6, all of which are prenylated, as well as the Nterminal portion of retinitis pigmentosa GTPase regulator and Arl2/Arl3, which are not prenylated. We show by immunocytochemistry with a PDE␦-specific antibody that PDE␦ is present in rods and cones. We find by yeast two-hybrid screening with a PDE␦ bait that it can interact with farnesylated rhodopsin kinase (GRK1) and that prenylation is essential for this interaction. In vitro binding assays indicate that both recombinant farnesylated GRK1 and geranylgeranylated GRK7 co-precipitate with a glutathione S-transferase-PDE␦ fusion protein. Using fluorescence resonance energy transfer techniques exploiting the intrinsic tryptophan fluorescence of PDE␦ and dansylated prenyl cysteines as fluorescent ligands, we show that PDE␦ specifically binds geranylgeranyl and farnesyl moieties with a K d of 19.06 and 0.70 M, respectively. Our experiments establish that PDE␦ functions as a prenyl-binding protein interacting with multiple prenylated proteins.