DNA to RNA

Vocabulary flashcards covering key terms and definitions related to transcription, RNA processing, RNA types, and ribosome biogenesis from the lecture notes.

Promoter

DNA sequence tell rna polymerase where transcription should begin

(in bacteria, sigma factor; in eukaryotes, recognized by transcription factors to recruit RNA polymerase II).

Sigma factor

Bacterial protein that guides RNA polymerase to promoter regions and is released after transcription initiation.

RNA polymerase II

Eukaryotic RNA polymerase that transcribes mRNA; requires general transcription factors and CTD phosphorylation for initiation and promoter escape.

TBP (TATA-binding protein)

Component of TFIID that recognizes the TATA box in promoters to help recruit RNA polymerase II.

TFIID

General transcription factor complex that recognizes promoter elements (including TATA) and helps recruit RNA polymerase II.

TFIIB

General transcription factor that aids promoter recognition and RNA Pol II recruitment.

TFIIF

General transcription factor that stabilizes RNA polymerase II during transcription initiation.

TFIIE

General transcription factor that assists in recruiting TFIIH to the transcription initiation complex.

TFIIH

Large multi-protein complex with helicase activity to open DNA and phosphorylate the RNA Pol II CTD to enable promoter escape.

5' cap

Modified guanine nucleotide added to the 5' end of eukaryotic mRNA that aids stability, export, and translation initiation.

Poly-A tail

Polyadenylation of the 3' end of mRNA; addition of adenines that influences stability and export.

Spliceosome

RNA-protein complex that removes introns and joins exons during pre-mRNA splicing.

Exon

Coding sequence retained in mature mRNA and ultimately translated.

Intron

Non-coding sequence removed during splicing.

Alternative splicing

Process by which different exons are included or excluded to generate multiple protein isoforms from a single gene.

CTD (C-terminal domain) of RNA Pol II

Part of RNA Pol II that, when phosphorylated by TFIIH, recruits capping, splicing, and 3' end processing factors and coordinates processing with transcription.

Nucleolus

Nuclear subdomain where rRNA transcription and ribosome biogenesis occur; a dynamic, membrane-less compartment.

rRNA

Ribosomal RNA; transcribed by RNA Pol I and forms the core structural/ catalytic components of ribosomes; lacks 5' cap and 3' poly-A tail.

mRNA

Messenger RNA; codifies protein sequences; transcribed by RNA Pol II and translated into protein.

tRNA

Transfer RNA; adaptor molecule that matches amino acids to codons during translation.

snRNA

Small nuclear RNA; component of the spliceosome involved in pre-mRNA splicing.

snoRNA

Small nucleolar RNA; guides chemical modification and processing of rRNA.

IncRNA (lncRNA)

Long noncoding RNA; diverse regulatory roles including scaffolding and gene expression regulation.

Telomerase RNA

RNA component of the telomerase enzyme that serves as a template to extend chromosome ends.

miRNA

MicroRNA; small RNA that regulates gene expression by blocking translation or promoting degradation of target mRNA.

siRNA

Small interfering RNA; directs degradation of specific mRNAs and helps establish repressive chromatin.

piRNA

Piwi-interacting RNA; protects germ line from transposable elements by silencing them.

Enhancer

Distal regulatory DNA element that increases transcription, often via looping to contact the promoter.

Mediator

A large coactivator complex that connects transcription factors at enhancers to RNA Pol II at the promoter.

Single-cell RNA sequencing

RNA-seq applied to individual cells to map cell types and gene expression profiles within a tissue.