Transcriptional Circuits Flashcards
What is definition of transcriptome?
Segment that is transcribed is referred to as transcriptome
What is abundant transcript?
Gene give a rise to many copies of RNA
If the abundant transcript is found in every cell this is called……
Housekeeping gene
What is rare transcript?
Gene is expressed at low levels
What are tissue specific genes?
This gene is expressed or not expressed in different cell types
What is inducible transcript?
Genes where transcription is induced in response to stimuli
This leads the rare transcript to become abundant transcript
What is meaning of promoter?
Sequence immediately 5’ to region to be transcribed
What is definition of enhancers?
Sequences of DNA that are not immediately adjacent to where transcription starts that act to enhance recruitment of RNA polymerase to promoter
They can reside to 5’ to 3’ + can be located within an intron
Contain DNA sequences that are very strong binding sites for specificity factors or transcription factors
Enhancers work in …………..
Position independent manner
Orientation independent manner
Recognition of promoters is mediated by initiation factors
Predominantly sigma factors bind to promoter region in prokaryotes
TFII basal transcriptional machinery in eukaryotes
Transcriptional switches
Prokaryotic: Lac-operon
Eukaryotic: oestrogen responsive transcription, tissue specific transcription (B globin), complex regulatory circuit (cell cycle)
Give an example of steroid hormone
Oestrogen
What is tamoxifen?
Compound used to treat breast cancer
Competes with oestrogen binding to receptor
What is ubiquitous factor?
Transcription factor that are expressed in all cell types
What is GATA-1?
Transcription factor that is only expressed in cells that will be committed to RBC.
