Analysis of Germination in Tomato Seeds

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Analysis of Germination in Tomato Seeds
Tammy Chan Department of Biology Mentor Dr. Hiro
Nonogaki (Horticulture)
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Importance of tomato seeds

• Agriculture and food source

• Carries genetic information

• Antioxidant

• Tomatina

Modified from http//groupenadatoulon.lautre.net/
IMG/jpg/Tomato-gene.jpg
http//www.umassvegetable.org/images/soils_crops_p
est_mgt/crop/tomato1.jpg
http//www.bereagardens.org/images/tomato_field.jp
g
Modified from http//upload.wikimedia.org/wikiped
ia/commons/8/88/Bright_red_tomato_and_cross_sectio
n02.jpg
http//www.telegraph.co.uk/news/graphics/2006/12/2
9/yearpix/060830tomatina.jpg
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Seed Morphology
Endosperm
Testa
Embryo
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Opposing Forces of Seed Germination
Embryo Growth Potential
Mechanical Resistance
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Mechanical Resistance
Testa
Radicle
Endosperm
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Endosperm Cap Composition
a-Galactosidase
ß - Mannosidase
ß - Mannanase
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RNAi
Start
Stop
Antisense
Sense
DNA
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RNAi
LeMAN2 mRNA
Interference
Hypothesis The endosperm cap of a tomato seed
is weakened by the function of LeMAN2 mannanase
during germination.
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Seed Germination Curve
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Characterization of RNAi plants
To check mRNA

• Tissue Printing

To check enzyme activity

• Gel Diffusion Assay

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Tissue Printing
Positively-charged membrane
Half seed
Paper towel
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Tissue Printing
RNA
Membrane
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Tissue Printing
WT
Vector
RNAi
WT
Vector
RNAi
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Gel Diffusion Assay
Endosperm Cap
Radicle
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Gel Diffusion Assay Results
Standard
Wildtype
Vector
RNAi
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Puncture Force Analysis
Endosperm cap
RNAi
Radicle Tip
Puncture Force (N)
WT
Imbibition Time (h)
Texture analyzer
Chen and Bradford (2000) Plant Physiol 124
1265-1274
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Acknowledgments
Dr. Kevin Ahern
Howard Hughes Medical Institute
Dr. Hiro Nonogaki
Seed Biology Lab
Dr. Po-Pu (Eric) Liu Dr. Masa Asahina Jessica
Kristof Jing Sun Jennifer Coppersmith
Jing
Me
Jen
Hiro
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