RNA Editing Flashcards
RNA editing targets ___ and ____ RNA
Coding, non-coding
RNA editing changes primary sequence of some RNA post __________
Transcriptionally
Purpose of RNA editing?
Regulating gene expression, increases proteome complexity, protects genome against some viruses
Two main types of RNA editing mechanisms:
1) Substitution editing 2) Insertion/deletion editing
Substitution editing examples:
1) Cytidine -> Uridine (C-U) 2) Adenosine -> Inosine (A-U) 3) Deamination 4) Base modifications that change chemistry of nucleotides
Insertion/deletion editing examples:
Cytidine, uridine, adenine nucleotides
Insertion/deletion editing organisms?
Slime mold (C), vertebrate (A), trypanosome (U)
Substitution editing organisms?
Animals (A-I), mammals (C-U), plant organelles (C-U)
Amino group removed from adenosine (deamination) happens in _____
A-I substitution editing
ADAR
Adenine deaminase in A-I editing
How does ADAR act?
Binds and modified dsRNA, interacts with minor shallow groove, low seq specificity
Biological function of A-I editing?
Controls activity of human Alu-elements, modifies ORFs of transcribed mRNAs, changes intron splicing signals, nuclear retention of some mRNAs (infection response)
______ are main targets of A-I editing in humans
Alu-elements (90% of human A-I editing)
Alu editing reduces dsRNA ___________
Structure regions
A-I editing mouse brain
Glutamine receptor GluR2 subunit, neurotransmitter, no editing leads to learning and memory defects
