Transthyretin slowly exchanges subunits under physiological conditions: A convenient chromatographic method to study subunit exchange in oligomeric proteins

Citation
F. Schneider et al., Transthyretin slowly exchanges subunits under physiological conditions: A convenient chromatographic method to study subunit exchange in oligomeric proteins, PROTEIN SCI, 10(8), 2001, pp. 1606-1613
Citations number
14
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
PROTEIN SCIENCE
ISSN journal
0961-8368 → ACNP
Volume
10
Issue
8
Year of publication
2001
Pages
1606 - 1613
Database
ISI
SICI code
0961-8368(200108)10:8<1606:TSESUP>2.0.ZU;2-O
Abstract
Transthyretin (TTR) subunits were labeled with a charge-modifying tag to ev aluate the possibility of subunit exchange between tetramers under physiolo gical conditions. Starting with a mixture of two TTR homote-tramers, one ha ving all subunits tagged at the N termini and the ether composed of untagge d subunits, heterotetramer formation as a function of time and temperature was evaluated using ion exchange chromatography. The data indicate that the subunit exchange can occur under native conditions at physiological pH in vitro, albeit slowly. Wild-type TTR exchanges subunits on a timescale of da ys at 37 degreesC and on a timescale of hours at 4 degreesC. The familial a myloid polyneuropathy-associated variant V30M exchanges subunits at the sam e rate as wild-type TTR at 4 degreesC but slower and less efficiently at 37 degreesC. Small molecule tetramer stabilizers abolish TTR subunit exchange , supporting a dissociative mechanism.