63 / 92
- 62 -
Polymers and Self Assembly: From Biology to Nanomaterials Poster Session I
40-POS
Board 40
Structural Characterization of the Interactions Between B-amyloid
1-40
Peptide and Alpha-
Synuclein Protein Involved in Lewy´s Body Diseases
Juliana Santana
UFRJ, Duque de Caxias, Brazil
Protein misfolding and aggregation are features shared by some proteins involved in
neurodegenerative diseases. The beta amyloid (AB) peptide, alpha synuclein protein (α-syn) and
Tau are related to Alzheimer's Disease (AD), Parkinson's (PD) and tauopathies. Those diseases
are implicated in amyloid fibril formation. The symptoms displayed by those diseases are similar
and results in cognitive and motor deficit. It has been proposed that the AB
1-40
and AB
1-42
peptide may be found in the extracellular environment in which it could form fibers or in the
intracellular environment maintaining its oligomeric form depending on the point at which the
amyloid precursor protein (APP) has been cleaved. The a-syn protein contains 140 amino acids
and initially observed to be localized at presynaptic terminals. In the case of dementia associated
with Lewys Bodies both the AB peptide and a-syn protein are found co-aggregated. Thus,
leading to the hypothesis that there is a synergism between the peptide and the protein to
promote the aggregation into fibrillar structures.This work aims to improve the knowledge
regarding the molecular interactions involved between the proteins (a-syn) and peptide AB
1-40
in
the formation of protein aggregates. For that, it has been applied fluorescence spectroscopy,
circular dichroism, Nuclear Magnetic Resonance State liquid and Solid State.The AB
1-40
peptide
was purified and the purity analyzed by SDS-PAGE gel. The oligomeric state of association
between AB
1-40
and alpha synuclein has been evaluated by means of fluorescence polarization
measurements, while the molecular interactions has been followed by Nuclear Magnetic
Resonance.