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Gene TechnologyGene Technology
Chapters 11 & 13
Gene Expression0Genome
0 Our complete genetic information
0Gene expression0 Turning parts of a chromosome “on” and “off”
Gene Expression0Uncoiled chromosomes are
called euchromatin0We have two parts to our
genes0 1. Introns
0Transcribed but not translated
0Cut out of mRNA before leaving nucleus
0 2. Exons0Transcribed and translated0Codes for a protein
http://highered.mcgraw-hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120080/bio31.swf
Transcription0DNA mRNA0After mRNA has been made in the nucleus
0 Introns are spliced out of the mRNA0 Exons bind together0 Addition of 5’ cap and poly A tail
Gene Regulation0Similar to bacteria except out genome is much larger
and more complex098% of our DNA does not code for a protein0Each person has a specific number of non-coding
regions between exons 0 Called VNTR (Variable Number Tandem Repeats)0 Nonsense repeats in tandem
DNA Identification0Used to identify criminals
in a crime scene or to see family relation
0Four steps to use DNA identification0 1. Isolate DNA (make
copies if small sample)0 2. Cut DNA in fragments
that are known VNTR areas
0 3. Sort DNA by size (using technology)
0 4. Compare size fragments to known samples
http://www.youtube.com/watch?v=ZxWXCT9wVoI
How to Make DNA Copies0Process called PCR
0 Technology where a small DNA sample can be amplified to many copies for analysis
PCR Steps01. Add sample of DNA, DNA polymerase enzyme, free
nucleotides (to make new strands with) and heat sample0 The heat will act like helicase and separate the strands
of DNA
PCR Steps02. Cool sample down so primers can be added to DNA
template strands
PCR Steps03. DNA polymerase attaches to primers and adds
nucleotides to rest of DNA template strands
PCR Steps04. Two new strands are made repeat process until
enough DNA sample
http://www.youtube.com/watch?v=2KoLnIwoZKU
http://www.youtube.com/watch?v=eEcy9k_KsDI
Cutting DNA0Technology that cuts long
strands of DNA0Biologists use restriction
enzymes in order to cut the DNA0 Biological scissors
0Restriction enzymes can recognize specific sequences and only cut in certain areas of DNA
Cutting DNA0Sometimes when restriction enzymes cut DNA they
leave an overhang0 Creates “sticky” ends where you can then add
recombinant DNA 0 Used to input DNA from other organisms into a genome
http://highered.mcgraw-hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120078/bio37.swf
Gel Electrophoresis0Technology that separates DNA fragments by size in a
gel to compare to known samples
Gel Electrophoresis0How to run a gel:01. DNA sample goes through restriction enzymes to
break into fragments of known VNTRs02. Each DNA sample (now cut up) gets added into its
own chamber well
Gel Electrophoresis03. Electric current is run through the gel for a specific
amount of time0 DNA is negatively charged0 End of gel is positively charged0 When current runs, the DNA fragments move towards
the end of the gel
Gel Electrophoresis04. DNA is transferred to a nylon membrane where
probes are added 0 Probes bind to complementary DNA
Gel Electrophoresis05. X-ray film exposes membrane
0 This creates a band pattern that is unique to each individual
0 Called a “bio fingerprint”0 You can create a permanent copy of results if needed to
file
Gel Electrophoresis0How to read results:
http://learn.genetics.utah.edu/content/labs/gel/
Recombinant DNA
0Genetic engineering: modifying a genome of living cell0 When you combine two
DNA strands from different organisms it is then called recombinant DNA
Cloning0Clone
0 Exact copy of DNA, a cell or an organism
0Clones can be created by inserting DNA into vectors0 Vectors are organisms that can replicate
itself 0Ex: bacteria, yeasts
Cloning01. Egg cells are extracted from one organism and the
nucleus is removed0 Nucleus removed because the DNA of the organism we
want needs to fuse into the egg
0Cells from organism we wish to clone are removed
Cloning02. Desired organisms cell is placed next to egg cell and
electric shock fuses the two cells into one0 This triggers the new embryo to begin to divide and
develop
Cloning03. Developing embryo is implanted in a surrogate
mother and after incubation period is over, a new baby organism is born with the exact same genetic information as original organism
http://www.youtube.com/watch?v=tELZEPcgKkE
http://www.youtube.com/watch?v=-Qry1gYYDCA
Vaccines0Substance containing all or part of a harmless strain
of a pathogen0 This gets introduced to our body and we build an
immunity for it creating a defense system against the pathogen called antibodies
0DNA vaccine: vaccine containing genes from pathogen but will not cause infection
http://highered.mcgraw-hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120078/bio39.swf
http://www.youtube.com/watch?v=SduMbjW2V9A
Agricultural Applications0Made plants more tolerable to our environment
0 Resistance to weeds 0 Added genes that would be harmful to insects and pests0 Increase nutritional value to some plants0 Ex: adding vitamin A to rice in Asia
http://www.youtube.com/watch?v=FTfuAbzAeB8 – food http://www.youtube.com/watch?v=JVIznPgdQSM – animals