lecture 5 Flashcards
(14 cards)
expression of eukaryotic genes is regulates through multiple..
protein-binding transcription-control regions
control regions close to the transcription initiation site
promotor-proximal elements
control regions distal to the transcription initiation site
enhansors
transcription activators and repressors are _____ proteins containing a ______ domain and one or more ___ or ___ repression domains
modular
DNA-binding
activation
repression
how do you find gene regulatory sequences
linker scanning-reporter gene
properties of promoters
- function within a short distance; several hundred bps from transcription initiation site
- immediately upstream or downstream from the initiation site
- position dependent: usually non-functional if moved
properties of enhancers
- can function over a long distance; over tens of kpbs from transcription site
- can be upstream, downstream, from the start or within introns
position independent : usually still functional when moved - orientation independent: function In either normal or the inverted orientation
what kind of proteins bind to the gene regulatory sequences?
Transcriptional activators and repressors
transcriptional activators or repressors often have independent ______ and _____
DNA binding domains
effector domains
____ is a sequence in a protein that based on similarity with other known functional domains is likely to produce a distinct 3D structure and distinct domain
Motif
___ is a prtion o fthe polypeptide with a specifc function
domain
a conserved peptide sequence found In domains with similar functions
Motif
Zn++ finger motif
Regularly spaced C and H amino acids
leu zipper motif is found in
protein dimerization domains
