transcription and translation part one

what os the central dogma of biology

infromation flows from the DNA to RNA to protein

what happens when a protein is needed

the dna sequence for that protein is copied into RNA

what is RNA

a usually single stranded molecule made of ribonucleotides with roles in information transfer, structure, catalysis, and regulation

What is a gene?

a segment of DNA that codes for a protein or functional RNA

What is transcription?

The process of copying DNA into RNA

What is gene expression?

What is gene expression?

How can gene expression vary?

Genes can be expressed at high or low levels

Why can cells produce large amounts of protein quickly?

Multiple RNA copies are made, and each RNA can be reused many times also known as amplifications

Structural difference between RNA and DNA?

RNA is usually single-stranded and can fold into many shapes

what are the functional roles of rna

carry info, form ribosomes, bring amino acids

what enzyme synthesizes rna

rna polymerase

what strand is used during transcription

template strand

what is the rna product called

rna transcript

can multiple rna polymerases transcribe one gene at once

yes

what is mrna

rna that codes for protiens

mrna in eukaryotes vs bacteria

carries instructions for one protien in eukaryotes but multiple for bacterai

what are noncoding RNAs

RNAs that do not code for proteins but have functional roles

what are the three stages of transcription

initation, elongation, termination

what happens in initation

RNA polymerase binds and transcription begins

What happens in elongation?

RNA nucleotides are added one by one

What happens in termination?

Transcription stops and RNA is released

What is a promoter?

DNA sequence where RNA polymerase binds

is the promoter transcribed

no

What is the sigma factor?

A protein that helps RNA polymerase recognize the promoter

what are the -35 and -10 regions

key promoter sequences recognized during initation

what happens to the sigma factor during elongation

it is released

direction of rna synthesis

5 to 3

direction rna polymerase reads dna

3 to 5

what is a terminator

dna sequence signaling transcription stop

is the terminator transcribed

yes

what happens after termination

rna polymerase detaches and sigma factor rebinds

what are general transcription factors?

proteins that help rna polymerase bind to DNA

which RNA polymerase requires general transcription factors.

RNA polymerase 2

what is the TATA box

a promoter

what is TBP

TATA-binding protein (part of TFIID)

What is the transcription initiation complex?

Assembly of transcription factors + RNA polymerase II

What releases RNA polymerase from the complex?

Phosphorylation by TFIIH

What helps RNA polymerase II move along DNA?

Elongation factors

How does RNA pol II terminate?

RNA is cut from transcript by proteins (no clear stop signal)

How does RNA pol III terminate?

Stops at a stretch of U’s

When does RNA processing occur?

Before transcription is complete

What are the 3 main processing steps?

capping, polyadenylation, splicing