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Microbiol Biotechnol Rep | Volume 1, Issue 2
November 16-17, 2017 Atlanta, Georgia, USA
Annual Congress on
Mycology and Fungal Infections
Aggregate formation by prionogenic proteins in yeast
Anastasia V Grizel
1
, Aleksandr A Rubel
1
and
Yury O Chernoff
1,2
1
St. Petersburg State University, Russia
2
Georgia Institute of Technology, USA
C
ross-beta protein polymers (amyloids) cause diseases in mammals and control heritable traits in yeast. Initial
amyloid formation is poorly understood. Amyloid (prion) form of the
Saccharomyces cerevisiae
protein
Sup35 ([
PSI
+
]) is induced by overproduction of the Sup35 prion domain (PrD) either in the presence of the
prion isoform of another protein (for example, Rnq1), or when Sup35 PrD is attached to another amyloidogenic
protein, e. g. human Abeta peptide. This is accompanied by generation of various types of protein aggregates,
among them filamentous structures representing intermediates of prion formation. We studied if filaments could
be formed by Sup35 PrDs from other yeast species, or by chimeric constructs including both Abeta peptide and a
fluorophore. Divergent Sup35 PrDs from various yeast species, or a chimeric protein composed of
S. cerevisiae
Sup35 PrD and human Abeta were tagged with fluorophores and expressed in the
S. cerevisiae
cells, either
containing ([
PIN
+
]) or lacking ([
pin
-
]) the Rnq1 prion. Sup35 PrDs from various yeast species differed from
each other by morphology of aggregates formed in the [
PIN
+
] cells. Some divergent proteins produced almost no
filaments, although this did not necessarily correlate with the evolutionary distance. The Sup35 PrD-Abeta-CFP
construct rapidly and efficiently formed dot-like aggregates in the [
pin
-
] cells. However, this aggregation
did not result in [
PSI
+
] induction, indicating that either prion formation or immobilization of full size sup35
into a prion is inhibited by the attachment of fluorophore to the C-terminus of Abeta. Supported by SPbSU
grant 1.50.1038.2014, RFBR 15-04-06650 and RSF 14-50-00069.
Biography
Anastasia V Grizel has received her PhD in Biophysics from Lomonosov Moscow State University in 2012, and performed postdoctoral studies at St. Petersburg
State University. She currently is a Research Scientist at St. Petersburg State University (Russia). Her area of research includes genetic, cytological and structural
analysis of protein aggregation, primarily in the yeast model. She has published six papers in scientific journals.
avgrizel@gmail.com