Arnold E. Ruoho

 

 

G-Protein Receptors, G-Proteins, Neurotransmitter Transporters and Sigma Receptors

E-mail: aeruoho@wisc.edu

Research Strengths: Membrane Excitability and Synaptic Transmission, Molecular Neuroscience, Neurobiology of Disease

The effort in my laboratory is directed at an understanding of the molecular mechanisms which underlie neurotransmitter release and receptor activation. Several families of proteins which are of specific biochemical interest to us are: (a) beta-adrenergic receptors and rhodopsin (b) GTP binding proteins, (c) catecholamine transport proteins, and (d) sigma receptors. Projects to identify structural and functional domains of adrenergic receptors and G-proteins include: (a) intermolecular interactions between G-proteins and receptors; (b) identification of the G-protein alpha-subunit interaction domain with effectors, such as the enzyme, adenylyl cyclase, and the gamma-subunit of cGMP phosphodiesterase; and (c) the three-dimensional structure of active domains of the G-protein linked receptors and adenylyl cyclase using NMR and crystallography approaches. These experiments utilize multiple methodological approaches, including baculovirus expression of receptors, synthesis and use of agonist and antagonist photoaffinity labels, and the application of 'tethered' photoactivatable molecules to probe G-protein structure and nearest neighbor interactions.

Selected Publications:

• Foley, K.F., M.E. Van Dort, M.K. Sievert, A.E. Ruoho, and N.V. Cozzi. 2002. Stereospecific inhibition of monoamine uptake transporters by meta-hydroxyephedrine isomers. J. Neural Transmission 109: 1229-1240. [PDF]
• Thiriot, D.S., M.K. Sievert, and A.E. Ruoho. 2002. Identification of human vesicle monoamine transporter (VMAT2) lumenal cysteines that form an intramolecular disulfide bond. Biochemistry 41: 6346-6353. [PDF]
• Thiriot, D.S. and A.E. Ruoho. 2001. Mutagenesis and derivatization of human vesicle monoamine transporter 2 (VMAT2) cysteines identifies transporter domains involved in tetrabenazine binding and substrate transport. J. Biol. Chem. 276: 27304-27315. [PDF]
• Wu, Z., D.S. Thiriot, and A.E. Ruoho. 2001. Tyrosine 199 in transmembrane domain five of the Beta2-adrenergic receptor interacts directly with the pharmacophore of a unique fluorenone-based antagonist. Biochem. J. 354: 485-491. [PDF]
• Wu, Z. and A.E Ruoho. 2000. A high-affinity fluorenone-based beta2-adrenergic receptor antagonist with a photoactivatable pharmacophore. Biochemistry 39: 13044-13052. [PDF]
• Lupardus, P.J., R.A. Wilke, E. Aydar, C.P. Palmer, Y. Chen, A.E. Ruoho, and M.B. Jackson. 2000. Membrane-delimited coupling between sigma receptors and K+ channels in peptidergic nerve terminals. J. Physiol. 526: 527-539. [PDF]
• Wilke, R.A., R.P. Mehta, P.J. Lupardus, Y. Chen, A.E. Ruoho, and M.B. Jackson. 1999. Sigma receptor photolabeling and sigma receptor-mediated modulation of potassium channels in tumor cells. J. Biol. Chem. 274: 18387-18392. [PDF]