Dystroglycan (DG) is an adhesion complex, expressed in a wide variety of tissues, formed by an extracellular and a transmembrane subunit, alpha-DG and beta-DG, respectively, interacting noncovalently. Recently, we have shown that the recombinant ectodomain of beta-DG, beta-DG(654-750), behaves as a natively unfolded protein, as it is able to bind the C-terminal domain of alpha-DG, while not displaying a defined structural organization. We monitored the effect of a commonly used denaturing agent, the anionic detergent sodium dodecyl-sulphate (SIDS), on beta-DG(654-750) using a number of biophysical techniques. Very low concentrations of SDS (less than or equal to2 mM) affect both tryptophan fluorescence and circular dichroism of beta-DG, and significantly perturb the interaction with the alpha-DG subunit as shown by solid-phase binding assays and fluorescence titrations in solution. This result confirms, as recently proposed for natively unfolded proteins, that beta-DG(654-750) exists in a native state, which is crucial to fulfill its biological function. Two-dimensional NMR analysis shows that SDS does not induce any evident conformational rearrangement within the ectodomain of beta-DG. Its first 70 amino acids, which show a lower degree of mobility, interact with the detergent, but this does not change the amount of secondary structure, whereas the highly flexible and mobile C-terminal region of beta-DG(654-750) remains largely unaffected, even at a very high SDS concentration (up to 50 mM). Our data indicate that SDS can be used as a useful tool for investigating natively unfolded proteins, and confirm that the beta-DG ectodomain is an interesting model system.
Bozzi, M., Di Stasio, E., Cicero, D.O., Giardina, B., Paci, M., & Brancaccio, A. (2004). The effect of an ionic detergent on the natively unfolded beta-dystroglycan ectodomain and on its interaction with alpha-dystroglycan. PROTEIN SCIENCE, 13(9), 2437-2445.
|Tipologia:||Articolo su rivista|
|Citazione:||Bozzi, M., Di Stasio, E., Cicero, D.O., Giardina, B., Paci, M., & Brancaccio, A. (2004). The effect of an ionic detergent on the natively unfolded beta-dystroglycan ectodomain and on its interaction with alpha-dystroglycan. PROTEIN SCIENCE, 13(9), 2437-2445.|
|IF:||Con Impact Factor ISI|
|Settore Scientifico Disciplinare:||Settore BIO/10|
|Revisione (peer review):||Sì, ma tipo non specificato|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1110/ps.04762504|
|Stato di pubblicazione:||Pubblicato|
|Data di pubblicazione:||2004|
|Titolo:||The effect of an ionic detergent on the natively unfolded beta-dystroglycan ectodomain and on its interaction with alpha-dystroglycan|
|Autori:||Bozzi, M; Di Stasio, E; Cicero, DO; Giardina, B; Paci, M; Brancaccio, A|
|Appare nelle tipologie:||01 - Articolo su rivista|