Transcription factors are crucial for gene regulation, impacting development, metabolism, and environmental response. They include activators, repressors, enhancers, silencers, and basal factors, which together control gene expression by binding to DNA sequences and influencing mRNA transcription. Their interaction with chromatin states determines the accessibility and expression of genes, playing a key role in cellular homeostasis and organismal adaptation.
Show More
Transcription factors are proteins that bind to specific DNA sequences and regulate gene expression
Activators and Repressors
Activators enhance gene expression while repressors diminish it
Enhancers and Silencers
Enhancers increase gene expression while silencers decrease it, and both can act at a distance from the gene they regulate
Transcription factors collaborate with RNA polymerase II to form the pre-initiation complex at the promoter region of genes, allowing for the accurate initiation of transcription
Basal transcription factors are necessary for the assembly of the transcriptional machinery at the promoter region of genes, enabling the initiation of transcription
Basal transcription factors, including TFIIA, TFIIB, TFIID, TFIIE, TFIIF, and TFIIH, collaborate to form the pre-initiation complex with RNA polymerase II at the promoter region of genes
Basal transcription factors are responsible for the precise positioning of RNA polymerase II at the start site of transcription on the DNA template
Activators and repressors modulate the frequency and efficiency of gene transcription by either enhancing or inhibiting gene expression
Activators
Activators can increase gene expression by facilitating the assembly of the basal transcription machinery or recruiting coactivators that modify chromatin structure
Repressors
Repressors can inhibit gene expression by interfering with the basal transcription machinery or recruiting corepressors that alter chromatin to a less accessible state
The interactions between activators and repressors are crucial for maintaining appropriate levels of protein production and cellular homeostasis
Enhancers and silencers are elements within the genome that fine-tune the expression of genes by either increasing or decreasing gene transcription
Enhancers
Enhancers can significantly increase gene transcription when bound by activator proteins
Silencers
Silencers can repress gene expression when bound by repressor proteins
The accessibility of enhancers and silencers is influenced by the chromatin state, which can be active, poised, or repressed, and can change in response to cellular signals
00
______ transcription factors are essential for starting transcription at a gene's promoter region.
Basal
01
Components of pre-initiation complex
TFIIA, TFIIB, TFIID, TFIIE, TFIIF, TFIIH, RNA polymerase II.
02
Role of pre-initiation complex in transcription
Facilitates accurate transcription initiation at gene promoter regions.
