MECHANISMS OF NEURONAL SURVIVAL AND DEATH

Document Sample
MECHANISMS OF NEURONAL SURVIVAL AND DEATH Powered By Docstoc
					Academic Stuff page

-> also mention “neuronal survival & death” at
“www.cns.song.ac.uk” page and at
“www.soton.ac.uk/pgresearch/topic/122.html” page

Picture ( I have send it by mail, letter)

Theme: Mechanisms of neuronal death and survival

Tel Number (former office of Dr. D. Anthony)
e-mail address (I will ask David and get it to you as soon
as known)
web address: please make a link to the Wyttenbach lab page
(see below)

Background

- Diploma/MSc in Biology, Institute of Zoology, University
of Basel, Switzerland

- PhD in Genetics, Institute of Zoology, University of
Lausanne, Switzerland

- Postdoctoral Fellow at the Department of Genetics,
University of Uppsala, Uppsala (Sweden) and at the
Department of Medical Genetics and Department of
Biochemistry at the University of Cambridge, Cambridge, UK

- Lecturer in cellular and molecular Neuroscience, Centre
for Neuroscience, School of Biological Sciences, University
of Southampton, Southampton, UK

Research interest

Neuronal death is central to the development and integrity
of the nervous system and dysregulation of mechanisms
controlling neuronal death and survival cause
neurodegenerative diseases. My interest is to understand
what signalling pathways sustain neuronal survival under
basal and stress conditions and how neurodegenerative
diseases modulate such pathways. We use defined cellular
model systems and explore how loss of trophic support,
genotoxic stress or neurodegenerative disorders associated
with protein misfolding and protein deposition in nerve
cells (e.g. Huntington’s- or Parkinsons’s disease) affect
neuronal survival. Genomic and proteomic approaches
combined with functional studies (biochemistry, cell
biology) allow us to elucidate these questions (please use
the above web-link for detailed description of ongoing
research).

Relevant References

Wong, H., Fricker, M, Wyttenbach, A., Tolkovsky, A.M (2004)
Mutually-exclusive subsets of BH3-only proteins are
activated by the p53 and JNK/cJun signalling pathways
during cortical neuron apoptosis by arsenite. Submitted
manuscript.

Yung, H. W., Wyttenbach, A., Tolkovsky, A.M (2004) Aggravation of
necrotic death of glucose-deprived cells by the MEK1 inhibitors U0126
and PD184161 through depletion of ATP. Biochemical Pharmacology, 68:
351-360.

Wyttenbach, A. (2004) Role of heat shock proteins during
polyglutamine neurodegeneration: mechanisms and hypotheses.
Journal of Molecular Neuroscience, 23: 69-95.

Edwardson J.M., Wang, C.T., Gong, B., Wyttenbach, A., Bai,
J., Jackson, M.B., Chapman, E.R., Morton A.J. (2003)
Expression of mutant huntingtin blocks exocytosis in PC12
cells by depletion of complexin II. Journal of Biological
Chemistry, 278(33): 30849-53.

Kita, H., Carmichael, J., Swartz, J., Muro, S., Wyttenbach,
A., Matsubara, K., Rubinsztein, D.C., Kato, K. (2002)
Modulation of polyglutamine-induced cell death by genes
identified   by   expression  profiling.  Human   Molecular
Genetics, 11(19): 2279-2287.

Wyttenbach A., Sauvageot, O., Carmichael, J., Diaz-Latoud,
C., Arrigo, A.P and D.C. Rubinsztein (2002). Heat shock
protein 27 protects against cellular polyglutamine toxicity
and suppresses the increase of reactive oxygen species
caused by huntingtin. Human Molecular Genetics, 11(9):
1137-1151.

Wyttenbach A., Swartz, J, Kita, H, Thykiaer, T, Carmichael,
J., Bradley, J., Brown, R., Maxwell, M., Schapira, A.,
Orntoft, T.F., Kato, K. and D.C. Rubinsztein (2001).
Polyglutamine   expansions  cause   decreased  CRE-mediated
transcription and early gene expression changes prior to
cell death in an inducible cell model of Huntington's
disease. Human Molecular Genetics 10(17): 1829-1845.

Ho, L.W., Carmichael, J., Swartz, J., Wyttenbach, A.,
Rankin, J., Rubinsztein, D.C. (2001). The molecular biology
of Huntington’s disease. Psychological Medicine, 31: 3-14.

Ho, L.W., Brown, R., Maxwell, M, Wyttenbach, A. and D.C.
Rubinsztein   (2001).   Wildtype  huntingtin  reduces   the
cellular toxicity of mutant huntingtin in mammalian cell
models   of  Huntington's   disease.  Journal  of   Medical
Genetics, 38(7): 450-452.

Wyttenbach, A., Carmichael, J., Swartz, J., Furlong, R.A.,
Narain, Y., Rankin, J. and D.C. Rubinsztein. (2000).
Effects of heat shock, heat shock protein 40 (HDJ-2) and
proteasome inhibition on protein aggregation in cellular
models of Huntington’s disease. Proceedings of the National
Academy of Sciences USA, 97(6): 2898-2903.

Coles,   R.,  Birdsall,   M.,   Wyttenbach,   A.  and   D.C.
Rubinsztein   (2000).   12-O-Tetradecanoylphorbol-13-acetate
downregulates the Huntingtin promoter at Sp1 sites.
NeuroReport, 11(14):1-5.

Rankin, J., Wyttenbach, A. and D. Rubinsztein (2000).
Intracellular    green  fluorescent protein-polyalanine
aggregates are associated with cell death. Biochemical
Journal, 348: 15-19.

Furlong, R.A., Narain, Y., Rankin, J., Wyttenbach, A. and
D.C.   Rubinsztein  (2000). -   synuclein  overexpression
promotes aggregation of mutant huntingtin. Biochemical
Journal, 346: 577-581.

D.C. Rubinsztein, J. Carmichael, J. Rankin, J. Chatelier,
A. Woolfson, A. Wyttenbach, C. Milstein and A.R. Fersht
(2000). The deleterious effect of polyglutamine aggregation
in cell models of Huntington’s disease. The American
Society for Human Genetics 2000. American Journal of Human
Genetics 2000, 67 (Supp 2): 410.

Rubinsztein D.C., Wyttenbach, A. and Rankin J (1999).
Intranuclear inclusions: pathological markers in diseases
caused by expanded polyglutamine tracts? Journal of Medical
Genetics 36: 265-270.
Narain, Y., Wyttenbach, A., Rankin, J., Furlong, R.A. and
D. Rubinsztein (1999). A molecular investigation on true
dominance in Huntington’s disease. Journal of Medical
Genetics, 36(10): 739-746.
  Lab home page


       ANDREAS WYTTENBACH’S LAB
Researc
h
                           Mechanisms of
                                neuronal
                  Our            and understand what
                       death is to survival
                       interest                              genes,
Vacanci           proteins and signalling pathways determine
es                neuronal   survival  under  basal    and   stress
                  conditions such as DNA damage, loss of trophic
                  support and protein misfolding due to genetic
                  mutations. The current focus is aimed at
                  exploring how intracellular protein misfolding
Lab               and aggregation impair survival signals and
Members           elicit various forms of neuronal dysfunction
                  and death. We use long polyglutamine stretches
                  that make proteins misfold and aggregate inside
                  neurons as a model system. The picture shows a rat
                                              PNS neuron infected in
                                              vitro with an adenovirus
Contact                                       expressing Exon 1 of the
                                              Huntington’s disease gene
                                              containing 103 glutamines.
                                              The green colour arises
                                              from the fusion of the
                                              transgene to the enhanced
                                              green fluorescent protein
                                              (EGFP).          Insoluble
                                              polyglutamine    inclusion
                                              bodies are formed in the
                                              soma          (arrowhead).
                                              Aggregates    are     also
                                              visible in the neurites
                                              (arrow).
Research pages




                 MECHANISMS OF NEURONAL
                   SURVIVAL AND DEATH

                 Processes of neuronal survival and death
   Researc       regulate the development of the nervous
   h             system, maintain the integrity of the human
                 brain     and     contribute    to     many
                 neurodegenerative diseases. The adult human
                 brain contains approximately 100 bilion
                 nerve cells (neurons) and ten times more
   Vacanci       supporting cells (glia). Considering the
   es            multitude of connections and interplay of
                 this cellular network, the human brain is
                 possibly   the   most   complex  biological
                 structure on planet earth.

   Lab           Most neurons do not divide and must survive
   Members       for long periods of time, maybe over a
                 lifetime.    Our   long-term    goal   is   to
                 understand what signalling pathways sustain
                 neuronal survival under basal and stress
                 conditions and how neurodegeneration caused
   Contact       by   protein    misfolding   and   aggregation
                 modulate such pathways. It is a great
                 challenge    to   understand   the   interplay
                 between survival and death signals within
                 and between brain cells and brain regions
                 and even between the brain and the rest of
                 the   body.   But   a   detailed   mechanistic
                 knowledge of such processes will reward
                 every person who is interested in how our
                 brain functions and survives. Furthermore,
                 it will form the basis of how to best
                 prevent neurodegenerative diseases.

                 By using defined cellular model systems we
                 are exploring how loss of trophic support,
                 genotoxic stress such as DNA damage or
                 intracellular    protein   misfolding    and
                 aggregation affect neuronal survival (see
                 Figure 1). I have started to elucidate how
                 neurotrophin   deprivation   (nerve   growth
                 factor) or DNA damage result in neuronal
                 death by concentrating on pro-apoptotic
                 proteins (e.g. p53, Bcl-2 proteins such as
                 Puma, Bim, Noxa) and anti-apoptotic heat
                 shock proteins (HSPs) and kinases (mainly
          Figure 1
Researc
h

           Loss of trophic        Protein         Genotoxic
            support (NGF)       misfolding          stress
                             and aggregation    (DNA damage)
Vacanci
es




Lab
Members




Contact        Apoptosis       Necrosis        Autophagic
                                                  death




          As a model of protein misfolding we are
          currently focusing on polyglutamine (polyQ)
          diseases.    There    are    >15    polyQ   diseases
          including   the    spinocerebellar     ataxias   and
          Huntington’s disease (HD). PolyQ diseases are
          caused by a CAG expansion in the coding region
          of a gene that leads to late-onset fatal
          neurodegeneration that typically begins in mid-
          life. Age of onset of the diseases correlates
          inversely with CAG repeat number where longer
          repeats lead to earlier age of onset and more
          severe pathology. Proteins containing polyQ
          expansions    misfold    and    form   intracellular
          protein    aggregates     made    of    amyloid-like
          fibrills that structurally resemble the fibrils
          found   in   amyloid    plaques     or  tangles   in
          Alzheimer’s    disease     or    Lewy    bodies   in
          Parkinson’s    disease.     The    fibrils   contain
          misfolded polyQ proteins with a beta-sheet
          conformation. The formation of polyQ aggregates
          results in a complex molecular cascade that is
          associated with neuronal dysfunction and death.
          Movie

Researc
h




Vacanci
es                               QuickTime™ and a
                               Cinepak decompressor
                           are neede d to see this picture.




Lab
Members




Contact

           Neuronal    precursor   cells    (PC12)    were
           engineered to express the first Exon of the
           Huntington’s disease protein containing 72
           glutamines    linked   to     enhanced    green
           fluorescent protein (EGFP) under the control
           of a doxycycline inducible promoter. After
           addition of doxycycline (1g/ml) cells turn
           green and produce intranuclear, insoluble
           polyglutamine aggregates (very bright spots).
           The movie consists of a series of pictures
           taken every 10 minutes over a total period of
           48 hours. It can be seen that some cells
           contain polyglutamine aggregates at time
           zero, but towards the end of the movie most
           cells   have   formed  aggregates,    show   an
           abnormal morphology and are detached from the
           culture dish. The polyQ aggregates deplete
           vital cellular factors such as Hsp40, Hsp70,
           the 20S proteasome and various transcription
           factors (e.g. CBP). The movie was recorded in
           collaboration with B. Gong and J. A. Morton,
          It is likely that toxic polyQ proteins
Researc   induce neuronal death that differ from
h         classical apoptosis or necrosis depending
          on the cell type and the stage of polyQ
          pathology. We have a strong interest in
          studying such alternative death pathways.
          In collaboration with Aviva Tolkovsky at
Vacanci   the Dept of Biochemistry in Cambridge we
es        are exploring the role of autophagy during
          polyQ neuronal death.

          A further project investigates how polyQ
          expansions induce free radicals (oxidative
Lab       stress) (ref 4) and how this in turn
Members   affects polyQ aggregation and neuronal
          death. The aim of this research is to
          tease out the mechanistic relationships
          between the production of reactive oxygen
          species (ROS), polyQ oligomerisation and
Contact   fibril formation and neuronal death in
          striatal neurons most vulnerable in HD. We
          focus on organelles that play key roles
          during ROS production and cell death
          decisions and are dysfunctional in HD: the
          mitochondria.   This    work   is    partly
          performed   in  collaboration   with   Mike
          Murphy at the Dunn Human Nutrition Unit
          (Wellcome Trust/MRC Building, University
          of Cambridge).

          It is increasingly being realized that
          neurodegenerative   diseases    such   as
          Alzheimer's disease, Parkinson's disease,
          Relevant publications
Researc
h
          1)   Wyttenbach, A., Carmichael, J., Swartz, J.,
               Furlong, R.A., Narain, Y., Rankin, J. and
               D.C. Rubinsztein. (2000). Effects of heat
               shock, heat shock protein 40 (HDJ-2) and
Vacanci        proteasome inhibition on protein aggregation
es             in cellular models of Huntington’s disease.
               Proceedings of the National Academy of
               Sciences USA, 97(6): 2898-2903.

          2)   Wyttenbach A., Swartz, J, Kita, H, Thykiaer,
Lab            T, Carmichael, J., Bradley, J., Brown, R.,
Members        Maxwell, M., Schapira, A., Orntoft, T.F.,
               Kato, K. and D.C. Rubinsztein (2001).
               Polyglutamine expansions cause decreased
               CRE-mediated transcription and early gene
               expression changes prior to cell death in an
Contact        inducible   cell   model   of   Huntington's
               disease. Human Molecular Genetics 10(17):
               1829-1845.

          3)   Kita, H., Carmichael, J., Swartz, J., Muro,
               S.,    Wyttenbach,    A.,     Matsubara,    K.,
               Rubinsztein,    D.C.,     Kato,    K.    (2002)
               Modulation of polyglutamine-induced cell
               death by genes identified by expression
               profiling. Human Molecular Genetics, 11(19):
Vacancy page


               Currently, there is an open position at the
               level of a research associate/junior postdoc
               for the duration of 4 years available to
               investigate    how    polyglutamine   (polyQ)
               expansion       mutations      result      in
               neurodegeneration. The successful candidate
               will first explore how misfolding and protein
               aggregation due to polyQ containing proteins
 Researc       results in the production of free radicals
 h             (oxidative stress) that are known to be a
               causative factor in polyQ pathology. This
               work will be done by use of cellular and
               mouse models of Huntington’s disease (HD). In
               a second step we will define the polyQ
 Vacanci       species (monomers, oligomers, fibrils) that
 es            is responsible for the induction of oxidative
               stress. The third aim of the study is to
               investigate the relationship between free
               radical production and neuronal death due to
               toxic polyQs by focusing on mitochondrial
 Lab           dysfunction in striatal neurons (susceptible
 Members       in HD).

               This project encompasses the use of a range
               of techniques of cell-and molecular biology
               and biochemistry (cell culture, live cell
 Contact       confocal microscopy, cloning, gene expression
               by adenoviruses, production of recombinant
               proteins, protein analysis by filtration
               assays and Western blotting). The successful
               candidate     should  be    able    to    work
               independently and is expected to have a solid
               practical background in one or two of the
               above-    mentioned  techniques    (preferably
               primary cell culture and cloning). Starting
               salary is 21,019 pounds sterling in the first
               year with increments in each successive year.

               Training will be provided in an exciting and
               competitive Neuroscience environment where
               scientists    share    their   enthusiasm  and
               knowledge in many aspects of Neuroscience
               (please   see    http://www.cns.song.ac.uk  or
               alternatively
               http://www.soton.ac.uk/pgresearch/topic/122.h
               tml). This work will be performed in the
               Neuroscience    Centre    at  the   School  of
               Biological      Sciences,     University    of
               Southampton. The University of Southampton
               has been listed in the top ten universities
Contact page

               Contact details until October 2004:

               Department of Biochemistry
               Hopkins Building
               Tennis Court Road
Researc        Cambridge CB 2 1QW/UK
h              Tel:      0044-(0)1223-339319
               Fax:      0044-(0)1223-333345
               e-Mail:   aw237@mole.bio.cam.ac.uk


Vacanci
es             Contact details after October 2004:

               School of Biological Sciences
               Neuroscience Centre (CNS)
               Bassett Crescent East
Lab            University of Southampton
Members        SO16 7PX, UK
               Tel
               Fax
               e-mail

Contact
Lab member page



…to be announced shortly
                           Researc
                           h




                           Vacanci
                           es




                           Lab
                           Members




                           Contact

				
DOCUMENT INFO
Shared By:
Categories:
Stats:
views:3
posted:3/2/2010
language:English
pages:13