Genome Engineering Flashcards
Why is bread wheat so complex
Hexaploid meaning it has 6 copies of its 7 chromosomes = 42 chromosomes
It’s genome is very large (16 billion base pairs) which is 5x human genome (80% is repetitive sequences)
How does powdery mildew disease effect cereals
Fungus blumeria graminis grows in high nitrogen fertilisation, cool, moist conditions help spread the spores and cause significant decline in yield.
What are the use of susceptibility gene mutants
Mutants in plant susceptibility genes show enhanced resistance like the recessive mlo allele which provides susceptibility to powdery mildew disease.
Inactivating these alleles through mutagenesis or genome editing can provide resistance in crops however this can have pleiotropic effects
What is genome engineering
Precisely changing an organism DNA.
Molecular scissors cutting out DNA and altering it or adding something new.
This can be done with TALENS or CRISPR.
How do programmable nucleases work
They induce targeted DNA double strand breaks which can be repaired by the cells natural mechanisms.
Non homologous end joining is a repair mechanism that joins broken ends without the use of a template.
This can cause insertions and deletions leading to gene knockouts.
Homology directed repair uses a homologous DNA template which can harness knocking in or gene correction.
How can cas9 be converted into a RNA guided gene regulator
A catalytically inactive version of cas9 (dcas9) which is defective in DNA cleavage.
A guide DNA directs dcas9 to a specific genomic loci allowing gene expression to be modified without altering the genetic sequence (by activating or repressing genes).
Advantages of DNA free genome editing in plants
Does not introduce any foreign DNA so takes away the negative perception that is ‘unnatural’ therefore making it easier to sell.
With the use of preassembled CRISPR-cas9 ribonucleoproteins you save time as it’s very efficient and precise
What is the biotechnological potential of algal genome engineering
Enhance production of biofuels (alcohol, hydrocarbons) by manipulating metabolic pathways (may make them more sustainable)
Environmental applications like carbon capture and bioremediation (removing pollutants from environmental)
