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E u r o S c i C o n C o n f e r e n c e o n
Neurology & Neurological
Disorders
Neurology 2018
J u l y 1 2 - 1 3 , 2 0 1 8
P a r i s , F r a n c e
Page 73
Journal of Neurology and Neuroscience
ISSN: 2171-6625
N
ystagmus is a condition of the eye characterized by an involuntary and
uncontrolled movement. It has a significant impact on vision in general
and can affect patient’s ability to lead an independent life. FERM domain-
containing 7 plasma membrane protein (
FRMD7
) is a member of the band
4.1superfamily of plasma proteins, found to be mutated in families with
nystagmus. The lack of
Frmd7
leads to deficit of direction selectivity in
mice retina by loss of asymmetric inhibition of direction-selective ganglion
cells (DSGC’s) by the starburst amacrine cells; the cells that express
Frmd7
. Experiments show no morphological alterations in these cells
upon loss of
Frmd7
. However, no evidence if the synapses between the
starburst amacrine cells and DSGC’s are affected. The aim of this poster
is to examine the integrity of the synapses of the starburst amacrine cells.
Methods:
SynapsesinfreshlyperfusedC57Bl6controlsvs
Frmd7
transgenic
knockout (
Frmd7
.
tm1b
) retina (N=5) were studied by immunohistochemistry
of frozen retinal sections.
Results:
Initial results show no significant deficit in the integrity of
synapses in the starburst amacrine (Acetylcholine transferase (ChAT)
expressing) cells in the mouse retina. Density and intensity of ChAT
expressing cells in C57Bl6 retina is similar to that of the
Frmd7
.
tm1b
. Also,
density of the presynaptic and postsynaptic markers, synaptophysin and
PDS95 respectively, is normal. In addition, density of gamma-Aminobutyric
acid (GABA), which is also expressed by the starburst amacrine cells, was
also normal.
Conclusion:
Frmd7
is somehow involved in modulating inhibitory signals
from the starburst amacrine cell to the DSGC’s in the retina. Level of general
pre-synaptic and post-synaptic markers in the
Frmd7
.
tm1b
transgenic retina
seem to be indistinguishable from wild type controls, so as expression
levels of acetylcholine and GABA, which indicates the synaptic markers
in the
Frmd7
.
tm1b
mice are similar to the wild type control mice. However,
the inhibitory feedback from the starburst amacrine cells to the DSGC’s is
compromised.
Role of Frmd7 in synaptic connectivity in the retina
Ahmed Salman, Diego Gomez-Nicola, Andrew Lotery and Jay Self
University of Southampton, UK
Ahmed Salman et al., J Neurol Neurosci 2018, Volume: 9
DOI: 10.21767/2171-6625-C1-009
Biography
Ahmed Salman obtained his BSc Honours degree in Genetics form the
University of Glasgow in 2009. He then studied for his MSc by research
in Brasenose college, University of Oxford, under the supervision of
Professor Elizabeth Robertson, investigating genes involved in early
mouse embryonic development. After finishing his Masters, he stayed
in the Robertson lab as a research assistant before joining the Welcome
Trust Centre for Human Genetics in Oxford, where he worked on the
mechanisms of double-stranded break repair for a year, before starting his
PhD in the University of Southampton in 2014, working on the role of Frmd7
gene in nystagmus, a significant eye disease characterised by involuntary
eyemovements. He is currently in the final year of studies aiming to submit
his thesis at the end of 2018.
as3e14@soton.ac.uk