AS.020.151 Chapter Notes - Chapter 13: Gel Electrophoresis, Dna Ligase, Electroporation
13.1 Recombinant DNA can be Made in the Laboratory
Conventional*breeding- many*generations,*only*one*species'*genes
Biotechnology- as*little*as*one*generation,*genes*from*any*organism
Recombinant+DNA- DNA*molecule*made*in*the*lab*derived*from*more*than*one*organism*(at*least*two*genetic*
sources)
Three+key+tools:
Restriction+enzymes for*cutting*DNA*into*fragments
•
Gel+electrophoresis for*analysis*and*purification
•
DNA+ligase for*binding*fragments*in*new*combinations
•
Restriction*enzymes
-Cut*DNA*at*specific*sequences*called*restriction*sites
-Cut*palindromic*sequences*(complementary*sequence*5'3*reads*same*as*original*5'3)
Bacteria*fight*invading*viruses- restriction*enzymes*recognize*foreign*DNA*and*cut*up*
Gel*electrophoresis
-DNA*fragments*separate,*indicating…
-number*of*fragments
-size*of*fragments
-relative*abundance*of*fragment*(intensity)
DNA*Ligase
-Enzyme*that*catalyzes*joining*fragments*of*DNA
-Some*with*different*DNA,*some*same
-So*some*recombinant*and*some*normal
13.2 DNA Can Genetically Transform Cells and Organisms
Recombinant*DNA*technology*can*be*used*to*clone genes
Transformation:*Recombinant*DNA*cloned*by*inserting*it*into*host*cell*(transfection if*host*is*animal)
Altered*host*is*transgenic
Methods for*inserting*the*recombinant*DNA:
-Chemicals*to*make*plasma*membrane*more*permeable
-Electroporation:*shock*creates*temporary*pores
-Viruses*and*bacteria*can*carry*recombinant*DNA*into*cells
-Inject*recombinant*DNA*into*nucleus*of*fertilized*egg->*transgenic*animals
-Gene*guns*can*shoot*host*cell*with*particles*of*DNA
Most*eukaryotic*genes*too*large*for*plasmid
Viruses*can*be*used*as*vectors
Viruses*infect*cells*naturally->*advantage*over*plasmids
Reporter+gene-gene*whose*presence*is*easily*observed
-like*gene*for*green*fluorescent*protein
13.3 Genes Come From Various Sources and Can be Manipulated
DNA*fragments*used*for*cloning*come*from*four*sources:
-gene*libraries
-reverse*transcription*from*mRNA
-products*of*PCR
-artificial*synthesis*or*mutation*of*DNA
Synthetic*DNA*can*be*manipulated*to*create*specific*mutations*to*study*consequences
Mutagenesis- revealed*many*cause*and*effect*relationships*(like*signal*sequences)
Knockout+experiment-inactivates*a*gene*so*that*it*is*not*transcribed*and*translated*into*a*protein
Another*way*to*study*gene*function:*block+translation
RNAi+(RNA+interference)- translation*of*mRNA*can*be*blocked*by*miRNAs*(degrade)*and*siRNAs*(bind*
and*degrade)
miRNA*and*siRNA- antisense+RNA
-can*be*synthesized*and*added*to*cells*to*prevent*translation*(effects*of*missing*protein*
determined)
13.4 Biotechnology Has Wide Applications
Almost*any*gene*can*be*inserted*into*bacteria/yeast*and*then*cells*induced*to*make*large*quantities
-Requires*specialized*expression+vectors (with*extra*genes*for*transgene*to*be*expressed*in*the*host*
cell)
Expression*vectors
Allow*to*produce*large*amounts*of*desired*protein
A*eukaryotic*expression*vector*has*a*promoter*and*poly-A*sequence
Pharming- production*of*pharmaceuticals*in*farm*plants*or*animals
Ie.*Transgenes*inserted*next*to*promoter*for*a*protein*in*milk
Transgenic*animal*produces*more*protein*in*its*milk
Bioremediation- use,*by*humans,*of*organisms*to*remove*contaminants*from*the*environment
Composting*and*wastewater*treatment
Concerns*of*biotechnology:
-Genetic*manipulation*is*unnaturally*interfering*in*nature
-Genetically*altered*foods*are*unsafe*to*eat
-Genetically*altered*crop*plants*are*dangerous*to*the*environment
Biotechnology*(Ch.*13)
Thursday, December 14, 2017
6:25 PM
13.1 Recombinant DNA can be Made in the Laboratory
Conventional*breeding- many*generations,*only*one*species'*genes
Biotechnology- as*little*as*one*generation,*genes*from*any*organism
Recombinant+DNA- DNA*molecule*made*in*the*lab*derived*from*more*than*one*organism*(at*least*two*genetic*
sources)
Three+key+tools:
Restriction+enzymes for*cutting*DNA*into*fragments
•
Gel+electrophoresis for*analysis*and*purification
•
DNA+ligase for*binding*fragments*in*new*combinations
•
Restriction*enzymes
-Cut*DNA*at*specific*sequences*called*restriction*sites
-Cut*palindromic*sequences*(complementary*sequence*5'3*reads*same*as*original*5'3)
Bacteria*fight*invading*viruses- restriction*enzymes*recognize*foreign*DNA*and*cut*up*
Gel*electrophoresis
-DNA*fragments*separate,*indicating…
-number*of*fragments
-size*of*fragments
-relative*abundance*of*fragment*(intensity)
DNA*Ligase
-Enzyme*that*catalyzes*joining*fragments*of*DNA
-Some*with*different*DNA,*some*same
-So*some*recombinant*and*some*normal
13.2 DNA Can Genetically Transform Cells and Organisms
Recombinant*DNA*technology*can*be*used*to*clone genes
Transformation:*Recombinant*DNA*cloned*by*inserting*it*into*host*cell*(transfection if*host*is*animal)
Altered*host*is*transgenic
Methods for*inserting*the*recombinant*DNA:
-Chemicals*to*make*plasma*membrane*more*permeable
-Electroporation:*shock*creates*temporary*pores
-Viruses*and*bacteria*can*carry*recombinant*DNA*into*cells
-Inject*recombinant*DNA*into*nucleus*of*fertilized*egg->*transgenic*animals
-Gene*guns*can*shoot*host*cell*with*particles*of*DNA
Most*eukaryotic*genes*too*large*for*plasmid
Viruses*can*be*used*as*vectors
Viruses*infect*cells*naturally->*advantage*over*plasmids
Reporter+gene-gene*whose*presence*is*easily*observed
-like*gene*for*green*fluorescent*protein
13.3 Genes Come From Various Sources and Can be Manipulated
DNA*fragments*used*for*cloning*come*from*four*sources:
-gene*libraries
-reverse*transcription*from*mRNA
-products*of*PCR
-artificial*synthesis*or*mutation*of*DNA
Synthetic*DNA*can*be*manipulated*to*create*specific*mutations*to*study*consequences
Mutagenesis- revealed*many*cause*and*effect*relationships*(like*signal*sequences)
Knockout+experiment-inactivates*a*gene*so*that*it*is*not*transcribed*and*translated*into*a*protein
Another*way*to*study*gene*function:*block+translation
RNAi+(RNA+interference)- translation*of*mRNA*can*be*blocked*by*miRNAs*(degrade)*and*siRNAs*(bind*
and*degrade)
miRNA*and*siRNA- antisense+RNA
-can*be*synthesized*and*added*to*cells*to*prevent*translation*(effects*of*missing*protein*
determined)
13.4 Biotechnology Has Wide Applications
Almost*any*gene*can*be*inserted*into*bacteria/yeast*and*then*cells*induced*to*make*large*quantities
-Requires*specialized*expression+vectors (with*extra*genes*for*transgene*to*be*expressed*in*the*host*
cell)
Expression*vectors
Allow*to*produce*large*amounts*of*desired*protein
A*eukaryotic*expression*vector*has*a*promoter*and*poly-A*sequence
Pharming- production*of*pharmaceuticals*in*farm*plants*or*animals
Ie.*Transgenes*inserted*next*to*promoter*for*a*protein*in*milk
Transgenic*animal*produces*more*protein*in*its*milk
Bioremediation- use,*by*humans,*of*organisms*to*remove*contaminants*from*the*environment
Composting*and*wastewater*treatment
Concerns*of*biotechnology:
-Genetic*manipulation*is*unnaturally*interfering*in*nature
-Genetically*altered*foods*are*unsafe*to*eat
-Genetically*altered*crop*plants*are*dangerous*to*the*environment
Biotechnology*(Ch.*13)
Thursday, December 14, 2017
6:25 PM
Document Summary
13. 1 recombinant dna can be made in the laboratory. Conventional breeding- many generations, only one species" genes. Biotechnology- as little as one generation, genes from any organism. Recombinant dna- dna molecule made in the lab derived from more than one organism (a sources) Dna ligase for binding fragments in new combinations. Cut dna at specific sequences called restriction sites. Cut palindromic sequences (complementary sequence 5"3 reads same as original 5"3) Bacteria fight invading viruses- restriction enzymes recognize foreign dna and cut up. 13. 2 dna can genetically transform cells and organisms. Recombinant dna technology can be used to clone genes. Transformation: recombinant dna cloned by inserting it into host cell (transfection if hos. Viruses and bacteria can carry recombinant dna into cells. Inject recombinant dna into nucleus of fertilized egg-> transgenic animals. Gene guns can shoot host cell with particles of dna. Viruses can be used as vectors ganism (at least two genetic ginal 5"3) if host is animal)