Gene structure and regulation Flashcards
eukaryote
organism composed of one or more cells containing visibly evident nuclei and organelles
prokaryote
Prokaryotes are organisms whose cells lack a nucleus and other organelles.
repressor protein
a protein coded for by a regulatory gene that prevents gene expression by binding to its operator
genome
the complete set of DNA housed within an organism
promoter
the sequence of DNA to which RNA polymerase binds
structural gene
a segment of DNA that doesn’t code for regulatory proteins, but instead codes for proteins that play a role in the structure or function of a cell or organism
trp operon
a series of genes within certain species of bacteria that encode for the production of the amino acid tryptophan
attenuation
mechanism for gene regulation within the trp operon whereby the premature ceasing of translation stops transcription when tryptophan levels are high
repression
mechanism for gene regulation within the trp operon whereby repressor proteins stop the initiation of transcription when tryptophan levels are high
regulatory gene
a segment of DNA responsible for producing proteins that control the expression of other genes
transcriptional factors
proteins that bind to the promoter region and control the functioning of RNA polymerase
attenuator sequence
part of the leader region within the trp operon that allows for attenuation
leader sequence
the segment of DNA or mRNA that immediately precedes the coding region.
terminator hair loop
a loop formed in mRNA in the presence
of tryptophan that ceases transcription of the trp operon
anti-terminator hairloop
a loop formed in mRNA when tryptophan is not present that ensures the transcription of the structural genes in the trp operon
