REPU MAGAZINE N 3
2016 REPU Research Projects
2017
2016 REPU Research Projects
By Luz Saavedra, Johnny Dávila and Ricardo Gonzales
REPU - Biology
Cayetana Arnaiz - Vanderbilt University
Graham Laboratory, USA
Plasma membrane asymmetry is essential for cell function and survival,
being required for cellular processes such as vesicular trafficking,
apoptosis, or more specific events, like blood clotting. The maintenance of
this asymmetry in lipid composition is done by a specific type of proteins
called the P4-type ATPases or 'flippases', which serve as translocators of
phospholipids within the membrane. The Graham Lab at Vanderbilt
University focuses on understanding how flippases contribute to the
establishment of membrane asymmetry and vesicle-mediated protein
transport. One of the ongoing projects at The Graham Lab aims to define
the mechanism of substrate recognition and translocation by flippases,
using genetic and biochemical approaches. Cayetana Arnaiz performed
several experiments with flippase knock-out yeast strains, to elucidate the
ability of these mutants to grow under stressful conditions, such as
alkaline environments. The aim of these experiments was to determine if
the function of these phospholipid translocators was essential to activate a stress response in the cell.
*Update: Cayetana is currently a PhD student at Vanderbilt University.
Jorge Rua - Vanderbilt University
Macara Laboratory, USA
Exocytosis is a conservative transport mechanism in eukaryotic cells by
which membrane proteins are transported and incorporated into or
secreted from the plasma membrane. The Exocyst is one of the
complexes involved in this process, being previously studied but whose
assembly is still not clearly understood. Overexpression of the subunits
could lead to wrong interpretations, that's why it is important to study
these proteins under physiological conditions.
The Macara lab, at Vanderbilt University, aims to understand cell polarity
of mammary gland epithelial cells and they have recently found that one
of the Exocyst subunits, EXO70, interacts with the polarity protein PAR3.
Jorge Rua used CRISPR/Cas9 technology to tag the endogenous locus of
EXO70 with super-folding GFP (sfGFP) in order to create a stable cell line
that enables the tracking of the Exocyst complex in live cells.
*Update: Jorge is currently a PhD student at Vanderbilt University.
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