Caenorhabditis elegansCaenorhabditis elegans(C. elegans)(C. elegans)

Kathy SzeniawskiKathy SzeniawskiClayton State UniversityClayton State University

Spring 2008Spring 2008

Alternate Food SourcesAlternate Food Sources

Population GrowthPopulation Growth

& Behaviors& Behaviors

C. elegansC. elegans Non ParasiticNon Parasitic ““Bacteria Bacteria

Eating” Eating” NematodeNematode

959 Somatic 959 Somatic CellsCells

Hermaphrodites Hermaphrodites and Malesand Males

Egg/Embryonic Egg/Embryonic StageStage

L1-L4 moltsL1-L4 molts ? Dauer Stage ? Dauer Stage

(Hibernation)(Hibernation) AdultAdult

Kathy Szeniawski

C. elegansC. elegans Natural Natural HabitatHabitat

Nutrient and Nutrient and Microorganism rich Microorganism rich organic materialorganic material

Cultures obtained Cultures obtained from from compost/garden compost/garden soil, rotting fruit soil, rotting fruit and mushroom and mushroom bedsbeds

Associated with Associated with millipedes, insects, millipedes, insects, snails and slugssnails and slugs

Photoblog.com Queensbury net

Paintworks

Why Why C. elegansC. elegans?? Easy/Inexpensive To Easy/Inexpensive To

MaintainMaintain Lives in a Petri DishLives in a Petri Dish Can be easily mutatedCan be easily mutated Feeds on OP-50 Feeds on OP-50 E. E.

colicoli Bacteria in the Bacteria in the lablab

Short Life Cycle/Can Short Life Cycle/Can produce several produce several generations in a short generations in a short period of timeperiod of time

Perfect for Genetic Perfect for Genetic ResearchResearch

Kathy Szeniawski

OP-50 OP-50 E. coliE. coli Grow OP-50 Grow OP-50 E. E.

colicoli at 37 degrees at 37 degrees C overnight in 2X C overnight in 2X YTB (Yeast Tryptone YTB (Yeast Tryptone Broth)Broth)

Pipette onto NGM Pipette onto NGM agar platesagar plates

Grow your Grow your “Bacterial Lawn” for “Bacterial Lawn” for 2 days2 days

Kathy Szeniawski

Kathy Szeniawski

Kathy Szeniawski

C. elegansC. elegans Worm Worm FarmingFarming

Prepare NGM agar Prepare NGM agar plateplate

Grow an OP-50 Grow an OP-50 E. E. colicoli lawn lawn

Chunk transfer or Chunk transfer or Single worm transferSingle worm transfer

Grow at room tempGrow at room temp Extract eggs from Extract eggs from

AdultAdult Worms can be frozen Worms can be frozen

Kathy Szeniawski

Kathy Szeniawski

Kathy Szeniawski

ContaminationContamination

Maintain Sterile TechniquesMaintain Sterile Techniques

Kathy Szeniawski

Kathy Szeniawski

Worm ResearchWorm Research Research papers on “Different food source” Research papers on “Different food source”

experiments used different strains of experiments used different strains of bacteriabacteria to to feed to the worms. feed to the worms.

I hypothesized that wild type worms in their I hypothesized that wild type worms in their natural environment consumed food items since natural environment consumed food items since the lab worms that were collected were located in the lab worms that were collected were located in compost piles, mushroom beds and rotten fruit. compost piles, mushroom beds and rotten fruit.

N2 wild type (normal) worms usedN2 wild type (normal) worms used Transfer worms onto plates containing food Transfer worms onto plates containing food

productsproducts Observe and document population growth and Observe and document population growth and

behaviorbehavior

What Will the Worms Eat?What Will the Worms Eat?

OP-50 BacteriaOP-50 Bacteria Fruit SnacksFruit Snacks TofuTofu Hoodia chewsHoodia chews Trail Mix (Assorted Trail Mix (Assorted

dried fruits and dried fruits and nuts)nuts)

SpinachSpinach MushroomsMushrooms

Project: 10 Plates of EachProject: 10 Plates of Each

SpinachSpinach MushroomMushroom Tofu Tofu BacteriaBacteria

Population Designation (0-5)Population Designation (0-5)

++

Swarm +++++Swarm +++++

++++++++Few on Surface Several on Surface

ResultsResultsMy Hypothesis is SupportedMy Hypothesis is Supported

Population

0

1

2

3

4

5

1 2 3 6 7 8 9 10 13 15

Days

Siz

e

Bacteria

Tofu

Spinach

Mushroom

All Populations Survived

ResultsResults

Population

0

1

2

3

4

5

1 2 3 6 7 8 9 10 13 15

Days

Siz

e

Bacteria

Tofu

Spinach

Mushroom

Bacteria and Spinach do not support population growth as well as Tofu and Mushrooms

Tofu

0

1

2

3

4

5

1 2 3 6 7 8 9 10 13 15

Days

Siz

e Bacteria

Tofu

Spinach

0

1

2

3

4

5

1 2 3 6 7 8 9 10 13 15

Days

Siz

e Bacteria

Spinach

Mushrooms

0

1

2

3

4

5

1 2 3 6 7 8 9 10 13 15

Days

Siz

e Bacteria

Mushroom

T test Day 8p valuesB/T= 9.915x10-6

B/S = 0.017B/M = 7.77x10-6

T test Day 15p valuesB/T = 0.020B/S = 1B/M = 1.62x10-6

Unusual Behaviors Unusual Behaviors ObservedObserved

Worms eating food productsWorms eating food products Egg laying balls of HermaphroditesEgg laying balls of Hermaphrodites Egg mounds visible to the naked eyeEgg mounds visible to the naked eye Larval worm ballsLarval worm balls Larval worms participating in CannibalismLarval worms participating in Cannibalism Larval worms killing and eating dust mitesLarval worms killing and eating dust mites Vortexes in foodVortexes in food

Egg Mounds, Worm Balls & Egg Mounds, Worm Balls & VortexesVortexes

Future ResearchFuture Research

Repeat experiment with controlled Repeat experiment with controlled seedingseeding

Use equal masses of food products Use equal masses of food products on all plateson all plates

Collect statistical data every day Collect statistical data every day – Population sizePopulation size– Amounts of Large worms vs. Small Amounts of Large worms vs. Small

wormsworms Observe behaviorObserve behavior

ConclusionConclusion

Different food sources CAN sustain Different food sources CAN sustain C. elegansC. elegans

Cannibalistic behavior observed several times; Cannibalistic behavior observed several times; Only larval worms observed participating in Only larval worms observed participating in cannibalismcannibalism

Larval worms observed killing/eating dust mitesLarval worms observed killing/eating dust mites Overall Population size quickly spikes, then Overall Population size quickly spikes, then

tapers off until only a few Dauer worms existtapers off until only a few Dauer worms exist Worm size in population tapers off to all small Worm size in population tapers off to all small

worms at the end of the growth curveworms at the end of the growth curve

Thank-YouThank-You

Dr. Francine Norflus, Research Dr. Francine Norflus, Research MentorMentor

Dr. Michelle FurlongDr. Michelle Furlong Larry and MaryEllen SzeniawskiLarry and MaryEllen Szeniawski Kheem TanKheem Tan Clayton State University Faculty and Clayton State University Faculty and

StaffStaff

ReferencesReferences Altn, Z.F. and Hall, D.H. 2005. Handbook of Altn, Z.F. and Hall, D.H. 2005. Handbook of C. ElegansC. Elegans

Anatomy. Introduction to C. Elegans Anatomy. In Anatomy. Introduction to C. Elegans Anatomy. In WormAtlas. WormAtlas. http://http://www.wormatlas.ord/handbook.contents.htmwww.wormatlas.ord/handbook.contents.htm

Kiontke, Karin. and Sudhaus, Walter. Ecology of Kiontke, Karin. and Sudhaus, Walter. Ecology of CaenorhabditisCaenorhabditis species. (January 09, 2006), Wormbook, ed. species. (January 09, 2006), Wormbook, ed. The The C. ElegansC. Elegans research community, Wormbook, research community, Wormbook, doi/10.1895/wormbook.1.37.1, doi/10.1895/wormbook.1.37.1, http://http://www.wormbook.orgwww.wormbook.org

Brenner, Sydney. The worm goes to school. 2003. Institute Brenner, Sydney. The worm goes to school. 2003. Institute of Molecular and Cell Biology and National Institute of of Molecular and Cell Biology and National Institute of EducationEducation

Barriere, Antoine. And Felix, Marie-Anne. Isolation of Barriere, Antoine. And Felix, Marie-Anne. Isolation of C. C. ElegansElegans and related nematodes. (July 17, 2006), Wormbook, and related nematodes. (July 17, 2006), Wormbook, ed. The C. Elegans research community, WormBook, ed. The C. Elegans research community, WormBook, doi/10.1895/wormbool.1.115.1 doi/10.1895/wormbool.1.115.1 http://http://www.wormbook.orgwww.wormbook.org

Shtonda, Boris and Avery, Leon. Dietary choice behavior in Shtonda, Boris and Avery, Leon. Dietary choice behavior in Caenorhabditis elegansCaenorhabditis elegans. 2006 The Journal of Experimental . 2006 The Journal of Experimental Biology 209, 89-102. Biology 209, 89-102.