TY  - JOUR
AU  - Thomaier, Maren
AU  - Gremer, Lothar
AU  - Dammers, Christina
AU  - Fabig, Judith
AU  - Neudecker, Philipp
AU  - Willbold, Dieter
TI  - High-Affinity Binding of Monomeric but Not Oligomeric Amyloid-β to Ganglioside GM1 Containing Nanodiscs
JO  - Biochemistry
VL  - 55
IS  - 48
SN  - 1520-4995
CY  - Columbus, Ohio
PB  - American Chemical Society
M1  - FZJ-2016-06573
SP  - 6662-6672
PY  - 2016
AB  - The interaction of the amyloid-β protein (Aβ) with neuronal cell membranes plays a crucial role in Alzheimer’s disease. Aβ undergoes structural changes upon binding to ganglioside GM1 containing membranes leading to altered molecular characteristics of the protein. The physiological role of the Aβ interaction with the ganglioside GM1 is still unclear. In order to further elucidate the molecular requirements of Aβ membrane binding, we tested different nanodiscs varying in their lipid composition, regarding the charge of the headgroups as well as ganglioside GM1 concentration. Nanodiscs are excellent model membrane systems for studying protein membrane interactions, and we show here their suitability to investigate the membrane interaction of Aβ. In particular, we set out to investigate whether the binding activity of GM1 to Aβ is specific for the assembly state of Aβ and compared the binding affinities of monomeric with oligomeric Aβ. Using fluorescence titration experiments, we demonstrate high-affinity binding of Aβ(1−40) to GM1 containing nanodiscs, with dissociation constants, KD, in the range from 25 to 41 nM, in a GM1 concentration-dependent manner. Biolayer interferometry experiments confirmed the high-affinity binding of monomeric Aβ(1−40) (KD of 24 nM to 49 nM) as well as of Aβ(1−42) (KD of 30 nM) to GM1 containing nanodiscs, and no binding to phospholipid containing nanodiscs. Interestingly, and in contrast to monomeric Aβ, neither oligomeric Aβ(1−40) nor oligomeric Aβ(1−42) binds to GM1 nanodiscs. To the best of our knowledge, this is the first report of a loss of function for monomeric Aβ upon aggregation.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000389557300008
C6  - pmid:27933798
DO  - DOI:10.1021/acs.biochem.6b00829
UR  - https://juser.fz-juelich.de/record/823945
ER  -