Mutations Flashcards
What is a mutation?
Changes in the DNA sequence from the original sequence
What does a point mutation do?
Changes just ONE nucleotide pair of a gene that changes the mRNA sequence
What do silent point mutations do?
affect the DNA and mRNA sequence but NOT the amino acid sequence.
What do missense point mutations do?
affect the DNA, mRNA sequence, and the amino acid sequence (amino acid substitution).
What do nonsense point mutations do?
introduce a stop codon into the mRNA sequence resulting in a non-functional protein.
What is an insertion?
The addition of nucleotides in mutation
What is deletion?
The taking away of nucleotides in mutation
What is duplication?
The duplicating of nucleotides in mutation
What do frameshifts do?
alter the reading frame of the mRNA and produce a completely different amino acid sequence or a premature stop codon.
What do nonframeshifts do?
involve multiples of 3 nucleotides that do not alter the reading frame (addition of deletion of an entire codon that results in addition or deletion of an amino acid).
What do post-translational modifications do?
to “fine-tune” proteins once they are translated to direct localization (signal-peptide), activate or inactivate proteins (phosphorylation), customize proteins for recognition (glycosylation), or turn transcription on or off (methylation).
What do signal peptides do?
Adds amino acids which helps target a protein to where it is supposed to be
What does kinase do?
Adds phosphate groups to phosphorylation
What do phosphatases do?
Removes phosphate groups from phosphorylation
What does phosphorylation do?
Adds a phosphate group to the amino acid group that activates or deactivates the protein function (on/off switch)
