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Tanaman Transgenik. Fifi Fitriyah Masduki 12 November 2010. Transgenics are a Biotechnology Product. Biotechnology - General Definition. The application of technology to improve a biological organism. Biotechnology - Detailed Definition. - PowerPoint PPT Presentation
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Tanaman TransgenikFifi Fitriyah Masduki12 November 2010
Transgenics are a Biotechnology Product
Sumber : Phil McClean, NDSU, 2003
Biotechnology - General DefinitionThe application of technology to improve a biological organism
Biotechnology - Detailed DefinitionThe application of the technology to improve the biological function of an organism by adding genes from another organisms
What About the TermGenetic Engineering?
Genetic engineering involves:
Isolating genes Modifying genes so they function better Preparing genes to be inserted into a new species Developing transgenes
Genetic engineering is the basic tool set of biotechnology
Sumber : Phil McClean, NDSU, 2003
What is a transgenic?
Transgene – the genetically engineered gene added to a species
Transgenic – an organism containing a transgene introduced by technological (not breeding) methods
GMO - an organism that expresses traits that result from the introduction of foreign DNA
Originally a term equivalent to transgenic organism
Why create transgenic plant?
Increase yield
Enhance Nutrition
Enhance taste
Why create transgenic plant?
Molecular Farming
Tembakau vs E. coli
• 1 tobacco plant = million seeds• The leaves of 1 tobacco plant produce more recombinant protein than a 300-liter fermenter in E. coli• It cost about 50x more to produce 1kg of a recombinat protein in E. coli than in trangenic plants
The Golden Rice Story
• Vitamin A deficiency is a major health problem
• Causes blindness• Influences severity of diarrhea, measles
• >100 million children suffer from the problem
• For many countries, the infrastructure doesn’t exist to deliver vitamin pills
• Improved vitamin A content in widely consumed cropsan attractive alternative
-Carotene Pathway Problem in Plants
IPP
Geranylgeranyl diphosphate
Phytoene
Lycopene
-carotene(vitamin A precursor)
Phytoene synthase
Phytoene desaturase
Lycopene-beta-cyclase
ξ-carotene desaturase
Problem:Rice lacks
these enzymes
NormalVitamin A
“Deficient”Rice
The Golden Rice Solution
IPP
Geranylgeranyl diphosphate
Phytoene
Lycopene
-carotene(vitamin A precursor)
Phytoene synthase
Phytoene desaturase
Lycopene-beta-cyclase
ξ-carotene desaturase
Daffodil gene
Single bacterial gene;performs both functions
Daffodil gene
-Carotene Pathway Genes Added
Vitamin APathway
is completeand functional
GoldenRice
The Roundup Ready Story
• Glyphosate is a broad-spectrum herbicide
• Active ingredient in Roundup herbicide • Kills all plants it come in contact with• Inhibits a key enzyme (EPSP synthase) in an amino acid pathway
• Plants die because they lack the key amino acids
• A resistant EPSP synthase gene allows crops to survive spraying
+ Glyphosate
X
Roundup Sensitive Plants
X
X
Shikimic acid + Phosphoenol pyruvate
3-Enolpyruvyl shikimic acid-5-phosphate(EPSP)
Plant EPSP synthase
Aromaticamino acids
Without amino acids, plant dies
X
BacterialEPSP synthase
Shikimic acid + Phosphoenol pyruvate
3-enolpyruvyl shikimic acid-5-phosphate(EPSP)
Aromaticamino acids
Roundup Resistant Plants
+ Glyphosate
With amino acids, plant lives
RoundUp has no effect;enzyme is resistant to herbicide
Insect resistant plant story
Source: USDA
Insect resistant cotton – Bt toxin kills the cotton boll worm• transgene = Bt protein
Insect resistant corn – Bt toxin kills the European corn borer• transgene = Bt protein
Normal Transgenic
Introducing the Geneor
Developing Transgenics
Steps
1. Create transformation cassette
2. Introduce and select for transformants
Transformation Cassettes
Contains
1. Gene of interest
• The coding region and its controlling elements
2. Selectable marker
• Distinguishes transformed/untransformed plants
3. Insertion sequences
• Aids Agrobacterium insertion
Transformation Steps
Prepare tissue for transformation
Introduce DNA
Culture plant tissue
• Develop shoots• Root the shoots
Field test the plants
• Leaf, germinating seed, immature embryos
• Tissue must be capable of developing into normal plants
• Agrobacterium or gene gun
• Multiple sites, multiple years
• Transformation cassettes are developed in the lab
• They are then introduced into a plant
• Two major delivery methods
Delivering the Geneto the Plant
• Agrobacterium
• Gene GunTissue culturerequired to generatetransgenic plants
Genome organization in plant
Chloroplast vs Nuclear
Chloroplast vs Nuclear
Chloroplast vs Nuclear
Chloroplast vs Nuclear
Chloroplast vs Nuclear
WT Flowers + transgenic pollen Transgenic Flowers + WT pollen
Chloroplast transformation
• Resistance shoot
• Heteroplasmy
• Homoplasmy
(Source: Bock and Khan 2004)
Edible VaccinesTransgenic Plants Serving Human Health Needs
• Works like any vaccine • A transgenic plant with a pathogen protein gene is developed• Potato, banana, and tomato are targets• Humans eat the plant • The body produces antibodies against pathogen protein• Humans are “immunized” against the pathogen• Examples:
DiarrheaHepatitis BMeasles
• .. Thanks for your attention!!
Basic Science Purpose
Basis for Plant Tissue Culture• Two Hormones Affect Plant Differentiation:– Auxin: Stimulates Root Development– Cytokinin: Stimulates Shoot Development
• Generally, the ratio of these two hormones can determine plant development:– Auxin ↓Cytokinin = Root Development– Cytokinin ↓Auxin = Shoot Development– Auxin = Cytokinin = Callus Development