Miscellaneous
Core enzyme
prokaryotic RNA polymerase consisting of α, α, β, and β' but missing σ; this complex performs elongation
Codon
three consecutive nucleotides in mRNA that specify the insertion of an amino acid or the release of a polypeptide chain during translation
Exon
sequence present in protein-coding mRNA after completion of pre-mRNA splicing
Promoter
DNA sequence to which RNA polymerase and associated factors bind and initiate transcription
Consensus
DNA sequence that is used by many species to perform the same or similar functions
Plasmid
extrachromosomal, covalently closed, circular DNA molecule that may only contain one or a few genes; common in prokaryotes
nucleotide from which mRNA synthesis proceeds in the 5' to 3' direction; denoted with a “+1”
RNA editing
direct alteration of one or more nucleotides in an mRNA that has already been synthesized
Anticodon
three-nucleotide sequence in a tRNA molecule that corresponds to an mRNA codon
Template strand
strand of DNA that specifies the complementary mRNA molecule
Nontemplate strand
strand of DNA that is not used to transcribe mRNA; this strand is identical to the mRNA except that T nucleotides in the DNA are replaced by U nucleotides in the mRNA
Signal Sequence
short tail of amino acids that directs a protein to a specific cellular compartment
Hairpin
structure of RNA when it folds back on itself and forms intramolecular hydrogen bonds between complementary nucleotides
Transcription bubble
region of locally unwound DNA that allows for transcription of mRNA
Preinitiation complex
cluster of transcription factors and other proteins that recruit RNA polymerase II for transcription of a DNA template
Splicing
process of removing introns and reconnecting exons in a pre-mRNA