Transcript Transposon - Mt. SAC Faculty Contact Directory

Transposon
“Jumping Genes”
DNA Sequence that moves from one location to another
Insertion Sequence
“retro” – made with transcriptase (like virsuses)
Transposon
Direct repeats
Composite
Adds extra genes between two insertions
Regulation of Metabolic Pathway
Regulate genes
Regulates enzymes
Operons
A unit of genetic material that functions in
bacteria and phages
Clustered gene with one promoter
On/off switch
Negative Gene Regulation
Repressible operons
Transcription is inhibited
Inducible operons
Transcription is stimulated
The trp Operon
Corepressor – absent makes tryptophan
Repressor
Corepressor – present stops tryptophan production
Corepressor – helper for repressor
lac operon
Lactose absent / repressor active – operon off
lac operon
Lactose present / repressor inactive – operon on
inducer
Positive Gene Regulation
cAMP
Accumulates when
glucose is scarce
Chromatin
Nucleosome
DNA and histone
proteins together
Repetitive DNA
Gene Amplification
Not passed to children
Embryos – ribosome production
Cancer cells – drug resistance
Questions???
Gene loss??
Gene rearrangement??
Genome??
Gene
Expression
Transcription Factors
A protein that binds to DNA and allows for
RNA polymerase to attach and begin
transcription
Enhancers – bends DNA to allow the factors to
be closer to the promoter region
RNA Splicing
Allows alternative mRNA molecules to be
built – ex. exons will act as introns
Recombinant DNA
Proteasome
A giant protein complex that destroys
proteins tagged for elimination by ubiquitin.
DNA Testing
PCR
RFLP
Practical Application
Diagnosis of Diseases
Human Gene Therapy
DNA Fingerprinting
Environmental Uses
Agricultural Uses
Human Genome Project
Safety and Ethical Questions
Pages 407-408 or 399