BCH 5413 University of Florida NEWEST EXAM 3 WITH
COMPLETE QUESTIONS AND CORRECT DETAILED
ANSWERS\VERIFIED 100% - LATEST UPDATE
if the chimeric animal is mated with one that is black and normal
for the gene of interest, three possible offsprings can be produced.
explain the genetics of each
- A/a, X-/X+: further screening to determine if knock out gene is
present (brown)
- A/a, X+/X+: further screening to determine if knock out gene is
present (brown)
- a/a, X+/X+: don't want because the black fur indicated no
knock out gene present
,in the RAI1 knock out example, panel B shows a southern blot with
the 3' prone and panel C shows a southern blot 5' probe. explain
why the wt mouse has a result of one band of a particular size
and the
heterozygous mouse has two bands of different sizes
- insertion of the knocked out gene replacement introduces
two new EcoR1 sites flanking the insert; this causes extra
cuts to be made and detected depending on which probe is
used
- 5' probe = regular 22.5 kb (from wt copy) and 13.1 kb (mutant copy)
- 3' probe = regular 22.5 kb (from wt copy) and 5.6 kb (mutant copy)
- wild type = 22..5 kb (carries two identical copies of the
normal gene with only 2 EcoR1 sites)
,what is the advantage of creating a cre/lox knockout mouse
instead of the traditional KO mouse
- traditional homologous KO have low survival
- cre/lx allows studying of the effects of the genes at
different times under varying conditions in certain tissues
where in genome are loxP sites located in a cre/lox model
flanking both sides of the KO gene
why does the loxP mouse need to be crossed with the cre mouse
to
create a functional system; explain the feature of this system
that allows the gene to be knocked out only under certain
conditions
- loxP mice are crossed with mice with the transgene cre
to allow recombination at loxP sites
- cre transgene comes with Alb promoter that only allows cre
function in the liver cells
, in which organism was the CRISPR system discovered
E coli
in the immunization phase, what happens to the foreign viral DNA
- CRISPR locus is initiated and CAS complex cuts the viral
DNA into spacers
- used as immunological memory for the bacteria for
secondary infections by the virus
in the immunity phase, what RNAs are present in the Cas9 complex
and what do they do
- crRNA: contains spacer sequence complementary to viral
DNA to guide Cas9 to correct DNA sequence
- tracrRNA: binds to crRNA to form active Cas9 complex to
recognize and cleave target DNA
COMPLETE QUESTIONS AND CORRECT DETAILED
ANSWERS\VERIFIED 100% - LATEST UPDATE
if the chimeric animal is mated with one that is black and normal
for the gene of interest, three possible offsprings can be produced.
explain the genetics of each
- A/a, X-/X+: further screening to determine if knock out gene is
present (brown)
- A/a, X+/X+: further screening to determine if knock out gene is
present (brown)
- a/a, X+/X+: don't want because the black fur indicated no
knock out gene present
,in the RAI1 knock out example, panel B shows a southern blot with
the 3' prone and panel C shows a southern blot 5' probe. explain
why the wt mouse has a result of one band of a particular size
and the
heterozygous mouse has two bands of different sizes
- insertion of the knocked out gene replacement introduces
two new EcoR1 sites flanking the insert; this causes extra
cuts to be made and detected depending on which probe is
used
- 5' probe = regular 22.5 kb (from wt copy) and 13.1 kb (mutant copy)
- 3' probe = regular 22.5 kb (from wt copy) and 5.6 kb (mutant copy)
- wild type = 22..5 kb (carries two identical copies of the
normal gene with only 2 EcoR1 sites)
,what is the advantage of creating a cre/lox knockout mouse
instead of the traditional KO mouse
- traditional homologous KO have low survival
- cre/lx allows studying of the effects of the genes at
different times under varying conditions in certain tissues
where in genome are loxP sites located in a cre/lox model
flanking both sides of the KO gene
why does the loxP mouse need to be crossed with the cre mouse
to
create a functional system; explain the feature of this system
that allows the gene to be knocked out only under certain
conditions
- loxP mice are crossed with mice with the transgene cre
to allow recombination at loxP sites
- cre transgene comes with Alb promoter that only allows cre
function in the liver cells
, in which organism was the CRISPR system discovered
E coli
in the immunization phase, what happens to the foreign viral DNA
- CRISPR locus is initiated and CAS complex cuts the viral
DNA into spacers
- used as immunological memory for the bacteria for
secondary infections by the virus
in the immunity phase, what RNAs are present in the Cas9 complex
and what do they do
- crRNA: contains spacer sequence complementary to viral
DNA to guide Cas9 to correct DNA sequence
- tracrRNA: binds to crRNA to form active Cas9 complex to
recognize and cleave target DNA
