Chapter 29. RNA Synthesis and Processing Flashcards
Idealized base sequence that represents common features of a promoter site.
Consensus sequence
an ATP-dependent helicase in bacteria that breaks the RNA-DNA hybrid at the transcription bubble, and thereby terminates transcription.
Rho (ρ) protein
Secondary structures formed by some mRNA molecules that can bind small molecules. Such binding then regulates the synthesis of the mRNA molecule.
Riboswitch
The unspliced, immediate product of RNA polymerase II in eukaryotes.
Pre-mRNA
A specific sequence of DNA, usually just upstream of a gene, that specifies the site and extent of transcription of the associated gene.
Promoter site
A structure at the 5’ end of eukaryotic mRNA that stabilizes the mRNA and enhances its translation. The cap contains a 7-methyl guanylate residue attached by a triphosphate linkage to the sugar at the 5’ end of the mRNA in a rare 5’-5’ linkage.
5’ cap
A domain in eukaryotic RNA polymerase II consisting of repeats of the seven-amino-acid sequence YSPTSPS that plays a role in transcription regulation through its binding to an enhancer-associated complex called mediator.
Carboxy-terminal domain (CTD)
a class of enzymes that synthesize RNA molecules complementary to a DNA template.
RNA polymerase
DNA sequences which have no promoter activity themselves but which can greatly enhance the activity of other promoters. Enhancers can exert their stimulatory effect over a distance of several thousand nucleotides.
Enhancer
one of a class of RNA molecules that display enzymatic activity.
Catalytic RNA
a long (up to 250 nucleotides) polyadenylate segment that is added post-transcriptionally to the 3 inch end of most eukaryotic mRNA.
Poly(A) tail
Refers to introns that have the ability to remove themselves from the precursor RNA and assist in the splicing of exons to form mature RNA.
Self-splicing
The generation of unique but related mRNA molecules by the differential splicing of the pre-mRNA transcript. By allowing the synthesis of more than one mRNA molecule from a premRNA transcript, alternative splicing increases the encoding potential of the genome.
Alternative splicing
RNA molecule 22-nucleotides in length that possesses the regulatory activity when bound to members of a class of proteins called the Argonaute family.
microRNA
the change in the information content of RNA following transcription by processes other than RNA splicing.
RNA editing
Complexes that consist of one snoRNA and several proteins that direct the extensive modification, on both ribose and base components, of pre-ribosomal RNA.
Small nucleolar ribonucleoprotein (snoRNP)
the site of RNA synthesis or transcription. It contains the RNA polymerase, a locally melted “bubble” of DNA and helix consisting of the template strand and the newly synthesized RNA.
Transcription bubble
a protein that assists RNA polymerase in the initiation of RNA synthesis. Transcription factors bind to specific promoter elements.
Transcription factor
a promoter element found in nearly all eukaryotic genes giving rise to mRNA. The TATA box is centered between -30 and -90 of the transcription start site and has the consensus sequence 5inch TATAAAA 3inch.
TATA box
a component of bacterial RNA polymerase that enables the core RNA polymerase to recognize promoter sites.
Sigma (σ) subunit
The removal of introns and the ligation of exons from precursors of RNA to form mature RNA.
RNA splicing
a class of small RNAs that are confined to the nucleus. Some of these play a role in splicing.
Small nuclear RNA (snRNA)
DNA-directed synthesis of RNA catalyzed by RNA polymerase.
Transcription
Complexes, formed by the association of small nuclear RNA with specific proteins, that facilitate RNA splicing.
Small nuclear ribonucleoprotein particle (snRNP)
an assembly of proteins and small nuclear RNAs that splices primary transcripts to mature mRNA.
Spliceosome
