Team C
Genetic Control of Organ Size in
Fruit Flies
Amir Blocker
&
Olga Bernal
Objectives
(I) To observe field flies and lab flies.
(II) To understand how a tumor suppressor gene
regulates fly wing size.
Hypothesis
(I) Field flies are the same as lab flies.
(II) Tumor suppressor gene does not affect fly wing
size.
Background
 What are fruit flies?
 Fruit flies have been used in
genetics study for over 100 years.
 Application of fruit fly in human
disease study:
Thomas Hunt Morgan
(Nobel Laureate,1933)
• Cancer
• Neurological disease (Parkinson's,
autism)
• Immune disease
• Rhythm, vision, olfaction, audition,
learning/memory, courtship, pain
• Other processes, such as longevity
http://en.wikipedia.org/wiki/Drosophila_melanogaster
Background
 Short generation time of 10-14 days (compared to 25 years for human)
Life Cycle of
fruit flies
Materials and Methods – (I)
 Field Fly Trap Experiment
• Preparing the bottle: Cut a small U opening
Label
2 inch
Do Not Disturb
SEECoS Program
Experiment in Progress
Materials and Methods – (I)
 Field Fly Trap Experiment
• Preparing the bottle: Cut a small U opening
• Preparing the bait: Bananas are mashed and added into the
bottle. Add some yeast to promote fermentation.
Materials and Methods – (I)
 Field Fly Trap Experiment
• Preparing the bottle: Cut a small U opening
• Preparing the bait: Bananas are mashed and added into the
bottle. Add some yeast to promote fermentation.
• Deploying the trap: Attach the trap to a tree limb
• Checking the trap:
fly number, weather condition, bait condition
• Collecting flies from the trap
• Observing the flies
- Use dissecting microscope
- Body color, eye color, head shape, size, gender
Materials and Methods – (II)
 Examination of tumor suppressor gene function in
wing size
 Differentiating male and female flies under dissecting
microscope (with 100% accuracy)
female (♀)
Male (♂)
 Setting up crosses
Experimental Crosses: C5-Gal4 (♀) X UAS-mats (♂)
Control Crosses:
C5-Gal4 (♀) X Wild type flies (♂)
Note: The tumor suppressor gene, mats, is going to be expressed in fly
wings of the offspring.
Materials and Methods – (II)
X
Dissect fly wings using forceps
Mount fly wings on glass slides
Collect wing images using SPOT Camera and Software
Measure wing sizes using Image J software
Data analysis using Microsoft Excel
Results – (I)
 Field Fly Trap Experiment (2 weeks later)
front view
back view
Results – (I)
 Field Fly Trap Experiment
lab fly
field fly
 No difference was seen between the lab and field flies.
Results – (II)
 Examination of tumor suppressor gene function in
wing size
A, A’: wild type control flies
C5-Gal4 (control)
A
C5-mats
B
B, B’: flies carrying tumor
suppressor gene (mats)
Relative Wing Size
1.2
C5-Gal4
1
C5-mats
0.8
0.6
A’
B’
*
0.4
0.2
1
0.26
0
1
(n>20)
Conclusion
(I) Field flies we trapped belong to the same
species of lab flies.
Supporting hypothesis (I):
-- Field flies are the same as lab flies.
(II) Tumor suppressor gene reduces the wing size.
Denying the hypothesis (II):
-- Tumor suppressor gene does not affect fly wing
size.
Future Research
• Use different baits to see whether other species of
flies will be attracted.
• Examine the function of another kind of tumor
suppressor gene.
• Examine the function of tumor suppressor gene in
different tissues other than wings, such as eyes,
heads, legs, etc.
Acknowledgement
Faculty: Dr. Zhi-Chun Lai
Mentor: Ms. Xin Ye
Dr. Jackie Bortiatynski
Instructor: Mr. Eric Speight
Ms. Jody Markley
Mr. Derek Ja mes
All UBMS Staff