SPECIAL TRANSFERS and GENE REGULATION Flashcards
The use of the RNA molecule as a template to create another RNA moolecule
RNA replication
Enzyme used to create DNA from RNA
Reverse transcriptase
(DNA to protein) Using antibiotics that alter the mRNA selectivity of ribosomes allowing it to use ssDNA as a template
DNA translation
Certain gene are expressed under a particular biological circumstance
Regulation of gene expression
In E. Coli and many other bacteria, genes for several different proteins may be encoded on a single transcript in a unit called ———
OPERON
TRUE OR FALSE
The genes of an operon share the same transcriptional regulation, but are translated individually
TRUE
TRUE OR FALSE
E. coli activates transcription only when lactose is available for it to digest.
TRUE
cis regulators
P, O, CBS
trans-regulator (not necessarily need to be encoded on the same piece of DNA as the genes regulate
LacI
Binding of the ——— prevents RNA polymerase from binding to the promoter
repressor
codes for the homotetramer protein repressor
LacI
Trans-factor, allosteric activator of lac operon
CAP
low glucose, but the lactose is present
transcription occurs
High Glucose, inactive CAP; thus, transcription ———
will not occur
In lac operon, lactose acts as —————, as it binds to the repressor protein and render it inactive which allows transcription of the operon.
inducer
cis-regulatory elements; can be located near or far, and either upstream or downstream, from the promoter
ENHANCERS
Trans-regulatory element; Bind to enhancers and RNA pol to activate transcription
Transcription Factors
Development of a large, spiny pelvic fin in stickleback depends on the presence of a particular enhancer element upstream of a gene called
Pitx
any heritable change in phenotype that is associated with a change in something other than chromosomal DNA sequence
EPIGENETICS
Addition of methyl to inactivate specific gene expression
Methylation
found in E. coli bacteria, is a group of genes that encode biosynthetic enzymes for the amino acid tryptophan
TRP operon
Low levels of tryptophan indicates
active transcription, and inactive repressor
High levels of tryptophan implies
inactive transcription, and active repressor
tryptophan acts as co-repressor=off gene coding
Lac Z
β-galactosidase
Lac Y
galactoside permease or lac permease
Lac A
Transacetylase
a mechanism for reducing expression of the trp operon when levels of tryptophan are high
ATTENUATION
Trp Operon: —————–: Lac Operon: Inducible System
REPRESSIBLE SYSTEM
