Control of Gene Expression in Eukaryotes: Part I

These flashcards cover key terms and concepts related to the control of gene expression in eukaryotes, focusing on transcriptional mechanisms, regulatory elements, and protein motifs.

RNA polymerases I, II, and III

Enzymes responsible for transcribing different types of RNA in eukaryotic cells.

Basal transcription

The basic level of transcription that occurs in the absence of regulatory influences.

PIC (Pre-Initiation Complex)

A complex of proteins that assembles at the promoter to initiate transcription.

Heterochromatin

A densely packed form of DNA that is transcriptionally inactive.

Euchromatin

A loosely packed form of DNA that is associated with active transcription.

Proximal promoter

The region just upstream from the core promoter containing regulatory elements.

Promoter Proximal Elements (PPEs)

Regulatory elements located close to the promoter that enhance transcription.

Enhancers

Regulatory sequences that stimulate transcription from a distance.

Silencers

Negative regulatory elements that repress transcription of a target gene.

Transcriptional activators

Proteins that increase the likelihood of transcription of specific genes.

Transcriptional repressors

Proteins that inhibit the expression of genes.

Homeodomain proteins

Proteins with a conserved DNA-binding domain that play crucial roles in development.

Zinc finger motif

A protein structural motif used in DNA recognition and binding.

Leucine zipper

A protein dimerization motif characterized by leucine residues that facilitate protein dimerization.

bHLH (Basic Helix-Loop-Helix)

A protein motif that contains both a basic region for DNA binding and a helix-loop-helix structure for dimerization.

Combinatorial dimerization

The process by which different protein dimers form to regulate gene expression diversely.

Nuclear receptors

A class of proteins that act as transcription factors upon binding to hormones.