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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


Transcriptome sequencing and analysis of marine eukaryotic algae

    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


The molecular basis for the evolution of somatic cell differentiation in Volvox carteri

    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

    Christopher Tan - Honours Student

      Publication: Nedelcu AM and C Tan. 2007. Early diversification and complex evolutionary history of the p53 tumor suppressor gene family. Development Genes and Evolution 217: 801-806.

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2006


Programmed cell death genes in Volvox carteri

    Christopher Tan - Honours Student


Development of a Volvocales wiki: http://www.volvocales.pbwiki.com/

    Christopher Tan - Undergraduate Student

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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)

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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.

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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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This site was last updated 05/15/11