Current Projects
Fitness costs in Chlamydomonas rls1 transformants
Irina Chan (Work-Study) - spring 2016
Exploiting cancer's evolutionary vulnerablities
Irina Chan (NSERC USRA) - summer 2016
Using evolutionary theory and experimental evolution to address the role of multicellular tumor circulating clusters
Alex May (MSc exchange student and Research Assistant) - January 2015 - present
RECENT PROJECTS
2014 - 2015
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Transcriptome sequencing and analysis
of marine eukaryotic algae
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Linna Meng and Aurora Nedelcu -
with David R. Smith, UWO, Canada
The evolution of SAND domain
Aurora Nedelcu -
with Erik Hanschen, U Arizona, USA
Evolutionary consequences of loss of photosynthesis in Polytoma
Aurora Nedelcu -
with Adrian Reyes-Prieto, UNB, Canada
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The molecular basis for the evolution of somatic cell differentiation in Volvox carteri
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Stephan Koenig - PhD Student
Exposing evolutionary vulnerabilities to suppress cancer: Proof of principle using Volvox
Aleatha Lee - MSc student
Stress-induction of RegA in Volvox
Amal Alahmadi - undergraduate student
Summer 2013
Testing the oxidative theory of aging in Volvox carteri
Matheus Lima - Exchange student (Brasil)
Linna Meng - NSERC USRA student
The evolutionary history of the TAZ domain
Linna Meng - NSERC USRA student
2011-2012
| Senescence of somatic cells in Volvox carteri |
Jassy Meng - Honours student
| Programmed cell death in glaucophyte algae |
Josh Clowater
- Honours studenr
2007-8
RegA mutations Volvox carteri
Tyler Feeney - Research Assistant
| Evolution of the programmed cell death protein 2
(PDCD2) |
Emma Logan - Senior undergraduate student
| Lateral gene transfer in the closest unicellular
relatives of animals |
Isabelle Miles - NSERC undergraduate summer student
Kanishk Karol - NSERC undergraduate summer student
Ahmed Fagir - NSERC undergraduate summer student
Publication
in
JEB: Nedelcu AM, I Miles, K Karol, A Fagir. 2008. Adaptive eukaryote-to
eukaryote gene transfer: Stress-related genes of algal origin in the
closest unicellular relatives of animals. Journal of Evolutionary
Biology 21: 1852-1860
| Evolutionary history of p53 tumor suppressor gene
family |
| Programmed cell death genes in Volvox carteri |
Christopher Tan - Honours Student
Christopher Tan - Undergraduate Student
Back to Top
2005
| ROS-induced sex genes in Chlamydomonas reinhardtii |
Marcia English - Science
Co-op undergraduate student
| A p53-induced gene in Volvox carteri
|
Fei Liu - Undergraduate
Student
| Sex and programmed cell death as alternative responses
to oxidative stress |
Sarah Garnett - MSc
Student (2005-2006)
Back to Top
2004
| Programmed cell death in Volvox carteri |
Sankalp Bhavsar - NSERC
USRA summer undergraduate student
This project is a continuation of the work done by Sankalp
Bhavsar during his previous NSERC USRA, dealing with programmed cell death
(apoptosis) in the multicellular green alga Volvox carteri. During
this phase he will (i) quantify the increase in the level of cellular
reactive oxygen species (ROS) during heat-induced apoptosis, (ii) visualize
the formation of ROS using fluorescent microscopy, and (iii) test the effect
of caspase inhibitors on V. carteri apoptosis using the DNA-laddering
effect as a marker. As he is already familiar with growing and manipulating
the algae as well as with inducing apoptosis using a heat-stress, he will be
able to carry out these experiments and interpret the results with little
supervision. In addition, he will participate in the investigation of the
expression pattern (using RT-PCR) of a putative caspase-like gene and the
identification of a potential p-53 homolog. Besides the techniques he
acquired during his previous USRA, he will learn fluorescence microscopy as
well as molecular techniques (DNA and RNA extractions, gel electrophoresis,
and PCR). Lastly, he will help with the development of a recently initiated
web project, Volvocales Information Project (www.unbf.ca/vip), whose goal is
to integrate knowledge and data to promote Volvocales as a new model-system
for evolutionary studies, including the evolution of programmed cell death.
Back to Top
2003
| Sex, cell-cycle arrest and programmed cell death as
alternative responses to stress |
Marcia English - UNB SEED
summer undergraduate research assistant
Our long-term objective is to address the hypothesis that
sex, cell-cycle arrest and programmed cell death (PCD) evolved as
alternative responses to stress and its consequences, including the
over-production of DNA-damaging reactive oxygen species (ROS). During our
investigations of heat-induced sex in Volvox carteri we have noted
that the decline in the proportion of sexual progeny at high algal densities
is paralleled by an increase in the proportion of reproductive cells (gonidia)
that delay cleavage (i.e., the fast successive round of cell divisions that
result in the formation of the embryo). We have also noted that temperatures
slightly higher than the one used for inducing sex, or increased duration of
the heat-stress result in an apoptotic-like response in gonidia. This
project will undertake a systematic, comprehensive and quantitative approach
to assessing the relationship between levels of stress (and ROS) and types
of cellular response in V. carteri. Asexual females will be subjected
to various levels of heat-stress and the progeny will be monitored for the
occurrence of arrested gonidia, sexual forms, and apoptotic gonidia.
Intracellular levels of ROS will be measured using a dye that fluoresces in
the presence of hydrogen peroxide. The student will learn how to maintain,
grow and manipulate the algae; she will be responsible (with appropriate
supervision) for carrying out the experiments, collecting the data, and
interpreting the results both in terms of the specific experiments as well
as their significance to the evolution of cell-cycle arrest, sex and PCD as
alternative responses to stress.
| Reactive oxygen species and sex in the unicellular
green alga, Chlamydomonas reinhardtii |
Andrea Simmonds - NSERC
USRA summer undergraduate student
Our long-term objective is to address the hypothesis that
sex evolved as a responses to stress and its consequences, including the
over-production of DNA-damaging reactive oxygen species (ROS). This
particular project is designed to address the generality of our previous
findings (using antioxidants) regarding the involvement of ROS in the sexual
process in the multicellular green alga, Volvox carteri, by extending
these investigations to other lineages and other types of stress. As in most
facultatively sexual species, in Chlamydomonas reinhardtii sexual
development occurs during nutrient stress; the depletion of nitrogen in the
environment induces the formation of gametes. If ROS are involved in
nitrogen-depletion induced sex in C. reinhardtii, the proportion of
the gametes should be reduced in cultures treated with ROS-scavengers. We
will induce gametogenesis in a pair of two mating types, mt+ and mt- of
Chlamydomonas reinhardtii (UTEX 89 and UTEX 90) in the presence and
absence of ROS-scavengers. To assess the proportion of gametes we will score
the quadriflagellate cells (i.e., two mating biflagellate cells) and
biflagellate cells (i.e., vegetative asexual forms). We will use the ROS-scavengers
that we previously used to show the involvement of ROS in Volvox carteri's
sexual process, namely catalase and CuDIPSH. The student will learn how to
maintain, grow and manipulate the algae; she will be responsible (with
appropriate supervision) for carrying out the experiments, collecting the
data, and interpreting the results both in terms of the specific experiments
as well as their significance for the evolution of sex as a response to
stress.
| Reactive oxygen species and sex in the multicellular
green alga, Volvox carteri: Investigating the role of mitochondria |
Mononita Roy - NSERC USRA
summer undergraduate student
Our long-term objective is to test the hypothesis that sex
evolved as a responses to stress and its consequences, including the
over-production of DNA-damaging reactive oxygen species (ROS). This
particular project is designed to bring additional support to our previous
findings (using antioxidants) regarding the involvement of ROS in the sexual
process in the multicellular green alga, Volvox carteri. In this
project, we want to address the possibility that sex can be induced by
internal (not environmental) stress, via ROS produced by the mitochondria.
We will block the mitochondrial electron transport chain (which will
increase the level of intracellular ROS) and monitor the progeny for the
occurrence of sexual forms. The student will learn how to maintain, grow and
manipulate the algae; she will be responsible (with appropriate supervision)
for carrying out the experiments, collecting the data, and interpreting the
results both in terms of the specific experiments as well as their
significance to the evolution of sex as a response to stress (including the
hypothesized relation between the acquisition of mitochondria - during the
origin of the eukaryotic cell, and the origin of eukaryotic sex).
| The evolution of programmed cell death during the
unicellular-multicellular transition in the volvocalean green algal group |
Sankalp Bhavsar - NSERC
USRA summer undergraduate student
Our long-term objective is to understand the evolution of
programmed cell death (PCD) during the unicellular multicellular transition.
This project is intended to further investigate our previous findings on the
occurrence of apoptotic processes in unicellular and multicellular green
algae. We will investigate the role of reactive oxygen species (ROS) and
caspases as mediators and executors of PCD, respectively, by using ROS-scavengers
and caspase-inhibitors. PCD will be induced via heat and oxidative stress
(i.e., the addition of hydrogen peroxide). In multicellular lineages with
germ/soma separation, PCD will be also investigated with respect to the type
of cell, somatic or reproductive. PCD will be assessed cytologically (e.g.,
viability assays, nuclear fragmentation) as well as using molecular
approaches (i.e., the DNA-laddering effect). The student will learn how to
maintain, grow and manipulate the algae, as well as extract and separate DNA
(i.e., gel electrophoreses); he will be responsible (with appropriate
supervision) for carrying out the experiments, collecting the data, and
interpreting the results both in terms of the specific experiments as well
as their significance for the evolution of PCD during the
unicellular-multicellular transition.
| Reactive oxygen species and sex: Manipulating the
cellular antioxidant system in the green alga,
Volvox carteri |
Fei Liu - NSERC USRA
summer undergraduate student
Our long-term objective is to test the hypothesis that sex
evolved as a response to stress and its consequences, including the
over-production of DNA-damaging reactive oxygen species (ROS). This
particular project is designed to bring additional support to our previous
findings (using antioxidants) regarding the involvement of ROS in the sexual
process in the multicellular green alga, Volvox carteri. In this
project we will investigate the role of ROS in the sexual process by
altering the expression of cellular ROS-scavenging enzymes; for instance,
Allylisopropylacetamide (AIA) can decrease the catalase levels to almost
zero values. If ROS are involved in the sexual process, altering the
cellular anti-oxidant system should reflect in changes in the sex response.
Asexual females will be grown in the presence of this agent and the progeny
will be monitored for the occurrence of sexual forms. Intracellular levels
of ROS will be measured using a dye that fluoresces in the presence of
hydrogen peroxide. Changes in catalase’s expression levels will be
monitored using RT-PCR techniques. The student will learn how to maintain,
grow and manipulate the algae, extract RNA and perform RT-PCR and gel
electrophoresis; she will be responsible (with appropriate supervision) for
carrying out the experiments, collecting the data, and interpreting the
results both in terms of the specific experiments as well as their
significance for the evolution of sex as a response to stress.
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