Tài liệu Báo cáo khoa học: Olfactory receptor signaling is regulated by the post-synaptic density

Olfactory receptor signaling is regulated by the

post-synaptic density 95, Drosophila discs large,

zona-occludens 1 (PDZ) scaffold multi-PDZ domain

protein 1

Ruth Dooley1,2,*, Sabrina Baumgart2,*, Sebastian Rasche1

, Hanns Hatt1 and Eva M. Neuhaus3

1 Molecular Medicine Lab RCSI, Education & Research Centre Smurfit Building, Beaumont Hospital, Dublin, Republic of Ireland

2 Department of Cell Physiology, Ruhr University Bochum, Germany

3 NeuroScience Research Center, Charite´, Universita¨tsmedizin Berlin, Germany

Keywords

MUPP1; olfactory neuron; olfactory

receptor; PDZ protein; signal transduction

Correspondence

E. M. Neuhaus, NeuroScience Research

Center, Charite´, Universita¨tsmedizin Berlin,

10117 Berlin, Germany

Fax: +49 30 450 539 970

Tel: +49 30 450 539 702

E-mail: [email protected]

*These authors contributed equally to this

work

(Received 9 September 2009, revised 6

October 2009, accepted 12 October 2009)

doi:10.1111/j.1742-4658.2009.07435.x

The unique ability of mammals to detect and discriminate between thou￾sands of different odorant molecules is governed by the diverse array of

olfactory receptors expressed by olfactory sensory neurons in the nasal

epithelium. Olfactory receptors consist of seven transmembrane domain G

protein-coupled receptors and comprise the largest gene superfamily in

the mammalian genome. We found that approximately 30% of olfactory

receptors possess a classical post-synaptic density 95, Drosophila discs

large, zona-occludens 1 (PDZ) domain binding motif in their C-termini.

PDZ domains have been established as sites for protein–protein inter￾action and play a central role in organizing diverse cell signaling assem￾blies. In the present study, we show that multi-PDZ domain protein 1

(MUPP1) is expressed in the apical compartment of olfactory sensory

neurons. Furthermore, on heterologous co-expression with olfactory sen￾sory neurons, MUPP1 was shown to translocate to the plasma mem￾brane. We found direct interaction of PDZ domains 1 + 2 of MUPP1

with the C-terminus of olfactory receptors in vitro. Moreover, the odor￾ant-elicited calcium response of OR2AG1 showed a prolonged decay in

MUPP1 small interfering RNA-treated cells. We have therefore elucidated

the first building blocks of the putative ‘olfactosome’, brought together

by the scaffolding protein MUPP1, a possible central nucleator of the

olfactory response.

Structured digital abstract

l MINT-7290305: OR2AG1 (uniprotkb:Q9H205) physically interacts (MI:0915) with MUPP1

(uniprotkb:O75970) by anti tag coimmunoprecipitation (MI:0007)

l MINT-7289999, MINT-7290250, MINT-7290063, MINT-7290110: OR2AG1 (uni￾protkb:Q9H205) binds (MI:0407) to MUPP1 (uniprotkb:O75970) by peptide array (MI:0081)

l MINT-7290162: mOR283-1 (uniprotkb:Q9D3U9) binds (MI:0407) to MUPP1 (uni￾protkb:O75970) by peptide array (MI:0081)

l MINT-7290128: mOR-EG (uniprotkb:Q920P2) binds (MI:0407) to MUPP1 (uni￾protkb:O75970) by peptide array (MI:0081)

Abbreviations

CamKII, calcium ⁄ calmodulin-dependent protein kinase II; GABAB, c-aminobutyric acid receptor B; GFP, green fluorescent protein; GST,

glutathione S-transferase; HRP, horseradish peroxidase; INAD, inactivation no after potential D; MUPP1, multi-PDZ domain protein 1; OMP,

olfactory marker protein; OR, olfactory receptor; OSN, olfactory sensory neuron; PDZ, post-synaptic density 95, Drosophila discs large,

zona-occludens 1; RNAi, RNA interference; siRNA, small interfering RNA.

FEBS Journal 276 (2009) 7279–7290 ª 2009 The Authors Journal compilation ª 2009 FEBS 7279