Transcriptional Regulation in Eukaryotes (Session 30)

These flashcards cover key concepts of transcriptional regulation in eukaryotes, focusing on RNA polymerases, transcription factors, enhancers, and regulatory mechanisms.

RNA Polymerase I

Transcribes rRNA genes; produces long transcripts processed into 28S, 5.8S, and 18S.

RNA Polymerase II

Transcribes mRNAs, where introns are removed during splicing, and a polyA tail and 5' cap are added.

RNA Polymerase III

Transcribes tRNA genes and 5S rRNA.

Basal Transcription Factors

Help RNA polymerase II recognize the promoter and orient to the start site of transcription.

TATA Box

A DNA sequence that is recognized and bound by TATA box binding protein (TBP) during transcription.

Enhancers

Cis-acting DNA sequences that regulate gene expression and can act at a distance from the promoter.

Activators and Repressors

Activators enhance gene expression while repressors decrease it.

Looping Mechanism

Method by which enhancers interact with basal transcription machinery through looping DNA.

Combinatorial Control

Involves multiple factors working together to regulate gene expression complexity.

Myc

An activator involved in cell cycle control that forms heterodimers with Max to promote gene expression.

Translocation

A chromosomal rearrangement that can fuse the regulatory components of one gene with another.

Reporter Genes

Genes used to identify or characterize enhancers by monitoring their expression in regulatory contexts.

Cis-acting elements

Mutations in enhancers or promoters that affect transcription levels.

Trans-acting factors

Proteins, such as transcription factors, that influence transcription from a distance.