Biochemical analysis of oligomerization of expanded polyalanine repeat proteins
β Scribed by Jun Nojima; Yoko Oma; Eugene Futai; Noboru Sasagawa; Reiko Kuroda; Boris Turk; Shoichi Ishiura
- Publisher
- John Wiley and Sons
- Year
- 2009
- Tongue
- English
- Weight
- 300 KB
- Volume
- 87
- Category
- Article
- ISSN
- 0360-4012
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β¦ Synopsis
Abstract
Many human proteins contain amino acid repeats that can form homopolymeric amino acid (HPAA) tracts. HPAA tract proteins that contain polyalanine sequences promote diseases, including oculopharyngeal muscular dystrophy. The pathological properties of these proteins develop when the repeats match or exceed βΌ20 residues. We analyzed the oligomerization of yellow fluorescent protein (YFP) and GST fusion proteins containing >20 alanine repeats by using sucrose density gradient centrifugation. YFP and GST fusion proteins having 23 polyalanine residues sedimented readily in sucrose density gradients, suggesting instability and oligomerization of proteins with an excess of 20 alanine repeats. Moreover, GST fusion proteins were resistant to trypsin digestion after oligomerization. Oligomerized artificial proteins with long polyalanine repeats may be suitable models for studying polyalanineβrelated diseases. Β© 2009 WileyβLiss, Inc.
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