Prokaryotic Transcription glossary

Co-activator

A protein or protein complex that activates genetic transcription usually by binding to a transcription factor.

Co-repressor

a molecule that is capable of combining with a specific repressor molecule and activating it, thereby blocking gene transcription

Consensus sequence

sequence that comprises the most commonly encountered nucleotides found at a specific location in the DNA. 2 main ones are 10bp upstream of the TSS (-10) and -35 sequence (35bp upstream of the TSS).

Ligand

an ion or molecule that binds to a central metal atom to form a complex. Ligands are usually thought of as electron donors attracted to the metal at the centre of the complex. Metals are electron acceptors. They may be neutral or negatively charged species with electron pairs available. Water is a common ligand. Here a water molecule is shown with its two lone pairs of electrons.

Non-coding

DNA or RNA that is not translated into protein.

Polycistronic

a single mRNA (generated from multiple genes) generates multiple proteins.

Promoter

DNA sequence to which transcription apparatus binds so as to initiate transcription; it indicates direction and which strand of the DNA elongation occurs on, also contains TSS

RNA polymerase

Enzyme that synthesizes RNA by joining nucleotides together using a DNA template as a guide; its substrates are the four nucleoside triphosphates: A, G, C, and U

Transcription Start Site (TSS)

The first DNA nucleotide that is transcribed into RNA

Transcription factors

proteins that move into the nucleus to bind to specific sequences (response elements) and recruit additional proteins to stimulate transcription