Simone Zweers
Reference: Brooker, Genetics: Analysis and prinicples, 7th edition
Chapter 15: Gene regulation in eukaryotes: transcriptional and translational
regulation
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, Genetics summary – VU BMS 2020/2021
Simone Zweers
Reference: Brooker, Genetics: Analysis and prinicples, 7th edition
- Gene regulation = the phenomenon in which the level of gene expression is controlled
so that genes can be expressed at high or low levels
15.1: regulatory transcription factors
- Transcription factors are proteins that influence the ability of RNA polymerase to
transcribe DNA into RNA
- General transcription factors: required for the binding of RNA polymerase to the core
promoter and progression to the elongation stage
- Regulatory transcription factors: regulate the rate of transcription of target genes
influence the ability of RNA polymerase to begin transcription of a particular gene
recognize cis-acting elements near the promoter regulatory sequences, control
elements, regulatory elements
o Activators bind to enhancers
o Repressors bind to silencers
- Combinatorial control = most eukaryotic genes are regulated by many factors
- Transcription: factors that commonly contribute to combinatorial control:
o Activator proteins stimulate the ability of RNA pol. to
initiate transcription
o Repressor proteins inhibit initiation of transcription
o Small effector molecules, protein-protein interactions
or covalent modifications may modulate the function of
activators/repressors
o Regulatory proteins alter the composition/arrangement
of nucleosomes in the vicinity of a promoter
o DNA methylation can inhibit transcription preventing
the binding of an activator
o Formation of heterochromatin may inhibit gene
expression
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