Exam 5 Molecular Biology UPDATED
ACTUAL Questions and CORRECT
Answers
Genetically modified organism (GMO) - CORRECT ANSWER - Any microorganism,
plant, or animal in which genetic engineering techniques have been used to introduce, remove, or
modify specific parts of its genome.
Genetically modified animals - CORRECT ANSWER - -Study gene function and
regulation
-Lab animals manipulated to exhibit human diseases
-Understand and cure genetic diseases
-Generate new organisms for other fields of research
Genetically modified plants - CORRECT ANSWER - -GMO's show great promise in
improving agriculture:
-plants could be engineered to better tolerate temperatures or weather extremes, to contain
various vitamins, etc
-GM food have potential to end world hunger but there are fears that the disease or pest resistant
genes inserted into crop plants might escape into other plants, creating hard to control super
weeds.
Transgenic organism - CORRECT ANSWER - Carries transferred genetic material (the
transgene) that has been inserted into its genome at a random site.
Knockout organism - CORRECT ANSWER - Created by gene targeting - the replacement
or mutation of a particular gene.
Cloned organism - CORRECT ANSWER - A genetically identical organism produced by
nuclear transfer from adult somatic (body) cells to an unfertilized egg.
,Laboratory mouse model - CORRECT ANSWER - -Small
-hardy
-short life cycle
-genetics possible
-many useful strains and tools
Transgenic mice - CORRECT ANSWER - 1) 1980 - the first transgenic mouse was
produced by microinjection of foreign DNA into fertilized eggs.
2) 1982- "Super" mice expressing rat growth hormone gene coding sequence.
Transgenic mice: How to make - CORRECT ANSWER - 1. Microinjection of DNA into
the pronucleus of a fertilized mouse egg
2. Implantation of the microinjected embryo into a foster mother
3. Analysis of mouse pups and subsequent generations for the stable integration and expression
of the transgene
Pronuclear injection - CORRECT ANSWER - - Transgene: Minimal requirements for
expression of DNA?
--Promoter; gene (cDNA), polyA signal
-Critical window of time before pronuclei fuse to form a diploid zygotic nucleus. Foregin DNA
should be integrated into the genome prior to the doubling. Usually inject sperm pronucleus
since it is larger and closer to the egg surface.
Analysis of stable integration - CORRECT ANSWER - Two important questions:
1) Is there stable integration of the transgene into the mouse chromosome?
2) If the transgene is present, is it expressed appropriately?
-Success rate is 2.5-6% in mice
Tail Biopsies: DNA analysis by southern blot or PCR.
-Integration is random and occurs by non homologous recombination
, -More than one copy may be integrated
Analysis of transgene expression at level of transcription - CORRECT ANSWER - Use:
-Northern Blot
-RT-PCR
-In situ hybridization, etc
Analysis of transgene expression at level of translation - CORRECT ANSWER - Use:
-Western blot
-Immunohistochemistry
-GFP expression, etc
Inducible transgenic mice - CORRECT ANSWER - What can be done if the transgenic is
embryonic lethal?
-Inducible Tet-Off system
Tet inducible system (tet-on) - CORRECT ANSWER - Several mutations are introduced
into the tTA so that this transactivator binds the TRE in the presence of Dox or Tet.
Tet inducible system (tet-off) - CORRECT ANSWER - Tet responsive transcriptional
activator (tTA): a chimeric protein of EColi Tet-controlled repressor (tetR) and VP16
transactivation domain.
-tTA binds the Tet-response element (TRE) upstream of the minimal MV promoter in the absence
of Tetracyclin (Tet) or Doxycycline (Dox).
Gene targeted mouse models - CORRECT ANSWER - The ability to create a mouse of
any desired genotype.
- A US based consortium is systematically knocking out mouse genes one by one in embryonic
stem cells.
ACTUAL Questions and CORRECT
Answers
Genetically modified organism (GMO) - CORRECT ANSWER - Any microorganism,
plant, or animal in which genetic engineering techniques have been used to introduce, remove, or
modify specific parts of its genome.
Genetically modified animals - CORRECT ANSWER - -Study gene function and
regulation
-Lab animals manipulated to exhibit human diseases
-Understand and cure genetic diseases
-Generate new organisms for other fields of research
Genetically modified plants - CORRECT ANSWER - -GMO's show great promise in
improving agriculture:
-plants could be engineered to better tolerate temperatures or weather extremes, to contain
various vitamins, etc
-GM food have potential to end world hunger but there are fears that the disease or pest resistant
genes inserted into crop plants might escape into other plants, creating hard to control super
weeds.
Transgenic organism - CORRECT ANSWER - Carries transferred genetic material (the
transgene) that has been inserted into its genome at a random site.
Knockout organism - CORRECT ANSWER - Created by gene targeting - the replacement
or mutation of a particular gene.
Cloned organism - CORRECT ANSWER - A genetically identical organism produced by
nuclear transfer from adult somatic (body) cells to an unfertilized egg.
,Laboratory mouse model - CORRECT ANSWER - -Small
-hardy
-short life cycle
-genetics possible
-many useful strains and tools
Transgenic mice - CORRECT ANSWER - 1) 1980 - the first transgenic mouse was
produced by microinjection of foreign DNA into fertilized eggs.
2) 1982- "Super" mice expressing rat growth hormone gene coding sequence.
Transgenic mice: How to make - CORRECT ANSWER - 1. Microinjection of DNA into
the pronucleus of a fertilized mouse egg
2. Implantation of the microinjected embryo into a foster mother
3. Analysis of mouse pups and subsequent generations for the stable integration and expression
of the transgene
Pronuclear injection - CORRECT ANSWER - - Transgene: Minimal requirements for
expression of DNA?
--Promoter; gene (cDNA), polyA signal
-Critical window of time before pronuclei fuse to form a diploid zygotic nucleus. Foregin DNA
should be integrated into the genome prior to the doubling. Usually inject sperm pronucleus
since it is larger and closer to the egg surface.
Analysis of stable integration - CORRECT ANSWER - Two important questions:
1) Is there stable integration of the transgene into the mouse chromosome?
2) If the transgene is present, is it expressed appropriately?
-Success rate is 2.5-6% in mice
Tail Biopsies: DNA analysis by southern blot or PCR.
-Integration is random and occurs by non homologous recombination
, -More than one copy may be integrated
Analysis of transgene expression at level of transcription - CORRECT ANSWER - Use:
-Northern Blot
-RT-PCR
-In situ hybridization, etc
Analysis of transgene expression at level of translation - CORRECT ANSWER - Use:
-Western blot
-Immunohistochemistry
-GFP expression, etc
Inducible transgenic mice - CORRECT ANSWER - What can be done if the transgenic is
embryonic lethal?
-Inducible Tet-Off system
Tet inducible system (tet-on) - CORRECT ANSWER - Several mutations are introduced
into the tTA so that this transactivator binds the TRE in the presence of Dox or Tet.
Tet inducible system (tet-off) - CORRECT ANSWER - Tet responsive transcriptional
activator (tTA): a chimeric protein of EColi Tet-controlled repressor (tetR) and VP16
transactivation domain.
-tTA binds the Tet-response element (TRE) upstream of the minimal MV promoter in the absence
of Tetracyclin (Tet) or Doxycycline (Dox).
Gene targeted mouse models - CORRECT ANSWER - The ability to create a mouse of
any desired genotype.
- A US based consortium is systematically knocking out mouse genes one by one in embryonic
stem cells.
