CYTOGEN - TRANSCRIPTION

RNA POLYMERASE I IS FOUND AT?

NUCLEOLUS

PRODUCT OF RNA POLYMERASE I IS?

RIBOSOMAL RNA (rRNA)

RNA POLYMERASE II IS FOUND AT?

NUCLEUS

PRODUCT OF RNA POLYMERASE II IS?

PRE-mRNA WHICH IS PROCESSED INTO MATURE mRNA

RNA POLYMERASE III IS FOUND AT?

NUCLEOPLASM

PRODUCT OF RNA POLYMERASE III IS?

SMALLER FUNCTIONAL RNAs > tRNA, 5S rRNA, U6 snRNA

The process by which genetic information in DNA is transferred into RNA.

Transcription

The main enzyme responsible for synthesizing RNA using DNA as a template.

RNA polymerase

A specific DNA sequence that indicates where transcription of a gene begins.

Promoter

The first major stage of transcription, during which RNA polymerase and associated proteins assemble at the promoter.

Initiation

The stage of transcription in which RNA polymerase moves along the DNA template and continuously adds RNA nucleotides.

Elongation

The final stage of transcription, in which RNA synthesis stops and the transcript is released.

Termination

A complex formed when RNA polymerase binds to the promoter while the DNA strands are still paired.

Closed promoter complex

A complex formed when the DNA at the promoter opens and exposes the template strand.

Open promoter complex

The step in initiation in which RNA polymerase leaves the promoter and proceeds into elongation.

Promoter clearance

A promoter sequence for prokaryotes that combes before the TATAAT region.

TTGACA region

A prokaryotic promoter sequence where opening of the DNA duplex occurs.

TATAAT region

An important promoter sequence involved in eukaryotic transcription.

TATA box

Proteins that help mediate the binding and activity of RNA polymerase at eukaryotic promoters.

Transcription factors

Transcription factor that contains the TATA-binding protein responsible for recognizing the TATA box.

TFIID

Protein contained within TFIID that recognizes and binds to the TATA box.

TBP

Transcription factor that stabilizes the binding of TFIIB and TBP to the promoter.

TFIIA

Transcription factor that binds to TBP and recruits the RNA polymerase II-TFIIF complex.

TFIIB

Transcription factor that recruits TFIIH.

TFIIE

Transcription factor associated with preventing RNA polymerase II from binding to nonspecific DNA sequences.

TFIIF

Transcription factor that unwinds DNA at the promoter through helicase activity.

TFIIH

Regulatory proteins that assist RNA polymerase II, transcription factors, and mediators in assembling at the promoter.

Transcriptional activators

Proteins that help activators interact with RNA polymerase II and transcription factors.

Mediators

A temporarily unwound region of DNA formed while RNA polymerase moves along the template.

Transcription bubble

Molecules used as building blocks for RNA during transcription.

Ribonucleoside triphosphates

The four ribonucleoside triphosphates used to synthesize RNA.

ATP, UTP, CTP, and GTP

The direction in which a growing RNA transcript is synthesized.

5 prime to 3 prime direction

The end of the growing RNA molecule to which new ribonucleotides are added.

3 prime OH end

The DNA strand that determines the complementary sequence of the RNA being produced.

Template strand

Proteins involved in helping RNA polymerase remain associated during the elongation phase.

Elongation factors

A specific DNA sequence that signals RNA polymerase to stop transcription.

Terminator

A structure mentioned in the chapter that may serve as a signal associated with transcription termination.

Hairpin or stem-loop structure

The newly produced RNA molecule released when transcription terminates.

Primary transcript

The primary RNA transcript produced at the end of transcription that undergoes further modification.

Heteronuclear RNA or hnRNA

Modification involving the addition of a special structure to the 5 prime end of hnRNA.

5 prime capping

Modified guanine nucleotide added to the 5 prime end during RNA capping.

7-methylguanosine

7-methylguanosine

Polyadenylation

A chain of adenine residues added to the 3 prime end of an RNA molecule.

Poly(A) tail

Protein associated with the poly(A) tail that helps protect the 3 prime end from degradation.

Poly(A) protein

Process in which introns are removed and exons are connected together.

RNA splicing

Regions of the RNA transcript that are removed during RNA splicing.

Introns

Regions of the RNA transcript that are joined together and retained in the mature RNA.

Exons

Large RNA-protein complex responsible for recognizing splice sites and carrying out RNA splicing.

Spliceosome

Regions of the RNA transcript recognized by the splicing machinery to determine where cutting and joining occur.

Splice sites

Process in which the same primary RNA transcript can be spliced in different patterns to produce different mature RNAs.

Alternative splicing

Eukaryotic RNA polymerase mainly associated with transcription of ribosomal RNA and activity in the nucleolus.

RNA Polymerase I

Eukaryotic RNA polymerase responsible for transcription associated with protein-coding genes.

RNA Polymerase II

Eukaryotic RNA polymerase responsible for RNAs such as 5S rRNA, tRNA, and U6 small nuclear RNA.

RNA Polymerase III