Identification of brain proteins that interact with 2-methylnorharman. An analog of the parkinsonian-inducing toxin, MPP+.

Abstract

N-Methylated beta-carbolines, including 2-methylnorharman, are structural and functional analogs of the parkinsonian-inducing toxin, MPP+. We are investigating N-methylated beta-carbolines, including 2-methylnorharman, as possible etiologic factors in the pathogenesis of Parkinson's disease. The cellular targets of N-methylated beta-carboline-mediated cytotoxicity are unknown; therefore, we used the T7Select Phage Display System in a novel approach to identify brain proteins that bind to 2-methylnorharman. We incubated (biopanned) immobilized 2-methylnorharman with a phage display cDNA library that expressed a library of human brain proteins on the surface of bacteriophage T7. We washed off unbound phage, amplified the phage that were bound to 2-methylnorharman, and enriched for toxin-interacting phage by repeating the biopanning and amplification steps. The cDNA sequences from the toxin-interacting phage were used to derive the amino acid sequences of the phage-displayed proteins. Five of the six 2-methylnorharman-interacting proteins may have relevance to Parkinson's disease: alpha-tubulin, paraoxonase, dorfin, fatty acid binding protein, and platelet-activating factor acetylhydrolase. Dorfin has sequence homology with parkin, which is interesting because mutations in the parkin gene associate with early-onset Parkinson's disease. Our findings are the basis for future studies aimed at determining whether 2-methylnorharman affects the function of these specific proteins in vitro and in vivo.

• Authors: Debra A Gearhart, Patricia F Toole, J Warren Beach
• Journal: Neuroscience research (Neurosci Res) Vol. 44 Issue 3 Pg. 255-65 (Nov 2002) ISSN: 0168-0102 [Print] Ireland
• PMID: 12413654 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S., Research Support, U.S. Gov't, P.H.S.)

Chemical References

• DNA, Viral
• Indicators and Reagents
• Nerve Tissue Proteins
• Neurotoxins
• Peptide Library
• Recombinant Proteins
• Harmine
• 2-methylnorharman
• Collodion
• 1-Methyl-4-phenylpyridinium

Topics

• 1-Methyl-4-phenylpyridinium (chemistry)
• Amino Acid Sequence
• Brain Chemistry
• Chemical Phenomena
• Chemistry, Physical
• Collodion
• DNA, Viral (biosynthesis, genetics)
• Harmine (analogs & derivatives, chemistry)
• Humans
• Indicators and Reagents
• Molecular Sequence Data
• Nerve Tissue Proteins (chemistry)
• Neurotoxins (chemistry)
• Peptide Library
• Recombinant Proteins (biosynthesis, genetics)
• Reverse Transcriptase Polymerase Chain Reaction