Test 5: Flashcards
Which system is used for site-specific recombination events in genome engineering?
Cre-Lox system
What is the function of Cre recombinase?
It causes recombination at loxP recognition sites
What is the key advantage of the Cre-Lox system?
Cre acts independently of any other accessory proteins
Cre-lox system, derived from bacteriophage P1, is widely used for genetic engineering in eukaryotes. What component of the system was discovered by Nat L. Sternberg?
Cre recombinase
What was Nat L. Sternberg studying when he discovered Cre and its specific locus of crossover, lox?
The maintenance of bacteriophage P1 as a stable plasmid
Which of the following statements is true about the Cre-lox system?
It involves the Cre recombinase and its specific recognition sites, lox
What is the specific function of Cre recombinase in the Cre-lox system?
It mediates recombination events at lox recognition sites
What is the primary role of a bacteriophage?
To infect and destroy host bacterial cells
What is the composition of all bacteriophages?
Proteins and nucleic acids
How does a bacteriophage infect a host bacterium?
By attaching itself to the bacterium
What happens to a bacterium after it is infected by a bacteriophage?
It produces viral components
What is a prophage?
A bacteriophage genome integrated into a bacterial chromosome or existing as an extrachromosomal plasmid
What is the characteristic step of the lysogenic cycle of temperate phages?
Integration of prophages into the bacterial host
What role do prophages play in bacterial genetics and evolution?
They contribute to bacterial diversity and adaptation
What is the function of G418 or Geneticin in cells?
It blocks polypeptide synthesis
What type of cells does G418 affect?
Both prokaryotic and eukaryotic cells
How does resistance to G418 occur?
By the expression of the Neomycin resistance gene
Which gene confers resistance to G418?
Neomycin resistance gene
What is the purpose of using G418 in laboratory settings?
To select for cells with the Neomycin resistance gene
What is the outcome of weaker chimeras in terms of germline transmission?
They are less likely to have ES cell-derived gametes
What does a high degree of chimerism indicate regarding germline transmission?
It has no correlation with germline transmission
What does the process of backcrossing involve?
Mating a hybrid organism with one of its parents or a genetically similar organism
How many generations of backcrossing are required to obtain a pure inbred line?
10 generations
What term is used to describe the resulting line after 10 generations of backcrossing?
Congenic
