Cycloastragenol in Microgravity:
Its Effects on Telomerase Activation and
Telomere Longevity in Saccharomyces
cerevisiae
(the “Instant” Strain of Baker’s Yeast)
Team Members
Co-Principal Investigators: Sarah Higdon,
Sharmayne Siu, Lauren Takeyama, and Kyra
Yamamoto
Collaborators: Misako Benso, Katherine Cheng,
Monica De Jesu, Gillian Ferguson, Charmayne
Floyd, and Avishan Nikoui-Smith
Background
Telomerase is an enzyme that
lengthens telomeres and prevents the
gradual degradation of coding
genetic material in chromosomes.
Objective
To test the effects of the
Cycloastragenol drug on
telomerase in
Saccharomyces cerevisiae
(the “instant” strain of
baker’s yeast) and to
qualify whether or not the
telomerase works more
rapidly in microgravity.
Materials
• SAF-Instant
Instant Yeast
• Cycloastragenol
• Agar medium
• Phosphate buffer
saline
• Agarose
Initial Experiments
• Fluorescent In Situ Hybridization (FISH)
• Expensive/resource consuming
• Difficulties including:
▫ Cell wall lysis
▫ Inconsistencies in yeast telomere sequences
▫ Telomere primer
Experiments
Preliminary Experiment #1: Whether yeast growth
will be inhibited under microgravity
conditions (simulated using sea plaque
agarose)
Preliminary Experiment #2: Whether
Cycloastragenol promotes yeast growth
Preliminary Experiment #1
1.
2.
3.
4.
Autoclave 250 mL at 157◦ F(70◦ C)
Cool down to 95◦ F (35◦ C) , add 1.44 mg of yeast
Place in LAB-LINE ORBIT Environ-Shaker at 30◦F
Heat up to melt agarose, pour into 500ml centrifuge
tubes
5. Centrifuge for 10 min at 1500 RPM, removed excess
medium/agarose
6. Tenfold serial dilution
Preliminary Experiment #2
1. Add two capsules of Cycloastragenol to 250 mL of
medium and 1.44 mg of yeast, shake
2. Place in LAB-LINE ORBIT Environ-Shaker for 1.5
hour, pour into 500mL centrifuge tubes
3. Centrifuge for 10 min at 2000 RPM
4. Remove excess medium until only 100mL remaining
5. Filled four test tubes with 45mL of buffer
6. Tenfold serial dilution
7. Spectrometer
Conclusion
1. Yeast can grow in simulated microgravity
conditions
2. Cycloastragenol does not negatively affect the
growth of yeast or elicit abnormal responses in
organisms with cell walls
Acknowledgements
Mr. Wyeth Collo
Dr. Steven Smith and Dr. Laura Crocitto from City of Hope
Mr. Keith Derrick
San Marino High School
San Marino Unified School District
San Marino PTSA
Stephen and Mary Birch Foundation
CASIS
NanoRacks
National Center for Earth and Space Science Education
Subaru of America, Inc
Mr. Fadl Saadi and Mr. Dan Torelli from the California Institute of
Technology
Thank you!