mRNA modification

Transcription of mRNA starts with a ____ and ends with a _____

promoter, terminator

The specific sequence of mRNA is determined by the?

antisense strand

immediately after transcription there are three modification steps, what are they?

5’ cap, poly A tail, and splicing

The 5’ end of mRNA has a? 

7-methylguanosine cap 

What does the 5’ cap do?

Helps the mRNA get to the cytoplasm and is involved in splicing.

What is the poly A tail important for?

mRNA stability

RNAseq is a method that allows
researchers to?

define/describe the transcriptome in cells

Introns begin with? 

5’ GU

Introns end with?

3’ AG

What are processed pseudogenes?

non-functional gene copies that form when an mRNA molecule is reverse-transcribed into DNA and inserted into the genome at a new location

How can processed pseudogenes have negative effects? 

Because the open reading frame is intact, a functional protein can still be produced, making too much protein ( GOF) 

processed pseudogenes is missing what?

introns

Pseudogenes are missing what?

control region

What are constitutive exons?

consistently included in all or nearly all mRNA transcripts for a specific gene.

What is the wobble rule?

the base pairing between the third position of an mRNA codon and the first position of its corresponding tRNA anticodon is less strict, allowing a single tRNA to bind to multiple codons

What is alternative splicing?

One genomic locus has information to make
several distinct protein products

What is intron retention? 

a form of alternative splicing where an intron, which is normally removed from an RNA molecule, is instead kept in the mature messenger RNA (mRNA) transcript

What are canonical splice sites?

the boundary between an intron and an exon that are recognized for the process of removing introns from pre-mRNA

What are cryptic splice sites?

sequences that resemble canonical splice sites  but are not typically used during the splicing of a pre-mRNA

What does the activation of a cryptic splice site do?

Their activation can lead to alternative splicing outcomes like exon skipping or the inclusion of intronic sequences