Gene Expression Flashcards
What is euchromatin? colour?
open relaxed conformation. light bands
heterochromatin? colour?
closed condensed formation. dark bands
How are histones modified in euchromatin?
hyper acetylated
hyper methylated
How are histones modified in heterochromatin?
hypoacetylated,
hypo methylated
What happens when DNA is methylated?
silencing of genes
where is DNA usually methylated?
CpGs around promoters
gene expresison makes two things:
proteins and RNA products
where do you normally find heterochromatin?
closer to nuclear membrane as it’s less active
what needs to happen to chromatin to give access to transcriptional machinery?
remodelling via chemical modification (epigenetic markers)
how do you get protein diversity from genes? 2 reasons
- more than one promoter
2. alternative splicing
non-coding RNAs like siRNA involved with?
mRNA degradation
miRNAs can be involved in?
repressing mRNA translation
transcription begins where?
TATA box/promoters
3 kinds of non-coding RNAs
long non-coding RNAs
short-interfering RNAs
micro RNAs
4 things long non-coding RNAs can do?
- decoy
- scaffold (enhance or inhibit)
- guide
- enhancer