Megamecia

IntroductionModel Organism

Paramecium TetraureliaMutagen

Ultraviolet Radiation

Paramecium Tetraurelia

Ultraviolet RadiationElectromagnetic Spectrum

100 nm – 400 nm range

Causes pyrimadine dimers to form in DNA (Goodsell, 2001)Pyrimadine dimers may result in the formation of a point

mutation.

http://www.uvsciences.com/uvtech.html

Pyrimadine DimersCovalent bond between two adjacent pyrimadine

bases (Thyamine, Cytosine) Point Mutation – Transition Mutation

Switching of complementary base pairs A-T becomes G-C (Russell, 2010)

http://www.mun.ca/biology/scarr/F16-20,25.jpg http://www.uvsciences.com/images/dna.jpg

Methods500 μL culture samples added to tissue culture traySamples exposed to UV radiation in a UV chamber.

Exposed between 10 and 60 minutes in 10 minute intervals

MethodsCulture trays wrapped in tin foil immediately

after exposure.Paramecia have the ability to repair DNA while

exposed to white lightRepeated 30 minute exposure with new

samples200 μL klebsiella inoculated wheat media added

to each sample after exposureSamples checked periodically for changes

Photos taken using a digitial microscope and Applied Vision

Measurements done with Image J

RESULTS30 minutes was the

optimum time to keep the cells in UV light

Mutant cells were 22% larger in length & 15% larger in width

RESULTSMUTANTS CONTROL

DISCUSSIONOther mutations that weren’t able to be cultured

DISCUSSIONExperiment could be taken further

Analyze DNA to pinpoint where mutation occurred

Experimental errorsTissue culture trays should have been checked

for cells before exposure to Ultraviolet radiation

Ultraviolet radiation successfully caused a mutation

REFERENCESGoodsell, D.S. (2001). The Molecular Perspective: Ultraviolet Light and Pyrimidine Dimers. The Oncologist, 6(3), 298-

299. Retrieved from http://theoncologist.alphamedpress.org/cgi/content/full/6/3/298

Russell, P.J. (2010) iGenetics: A Molecular Approach 3rd Ed. San Francisco, CA: Pearson Education, Inc.