Non-Coding RNA and Disease Flashcards
importance of ncRNA in medicine
- involved directly in disease
- new therapeutic targets for treatment
- can be biomarkers for prognosis and diagnosis
- SNP in ncRNA genes associate with disease
examples of non-coding RNAs
transfer RNA = tRNA
ribosomal RNA = rRNA
can be broken down into long and small ncRNAS
have a variety of regulatory roles within the cell
examples of small ncRNAs
- microRNA (miRNA)
- transfer RNA (tRNA)
- small nucleolar RNA (snoRNA)
tRNA
carry amino acids to the message RNA in order to translate it into a protein
- vital for correct translation of proteins
- mutated in many mitochondrial maternally inherited disease
define snoRNA and examples of diseases
modify other types of ncRNA (e.g. rRNA and tRNA) regulating ribosomal biogenesis = translation of RNA to proteins
examples = Prada-willi and Angelman syndrome
miRNA
bind to mRNA and block protein assembling causing degradation of mRNA or block the process of protein formation = repress ‘target’
they are endogenous small inhibitory RNAs
how is miRNA related to cancer
miRNA repress the translation of oncogenes and tumour suppressors
examples of miRNA causing disease
down syndrome - 5 miRNA present of chromosome 21
Alzheimer’s disease - loss of miRNA causes increase in production of BACE1 enzyme which cleaves APP protein causing plaques in brain
examples of long non-coding RNAs
- XIST = x-inactivation specific transcription
- HOTAIR = HOX transcription antisense RNA (cancer)
- H19
how do SNPs cause disease
SNPs can alter the ability of the RNA to bind other RNAs or proteins so it cannot function properly, leading to development of disease
- SNPs affect function of ncRNAs therefore affect function of proteins
ncRNA biomarkers
RNA packaged in blood stream to resist degradation
can be found in a biopsy of tissue or body fluids
what percentage of RNA is non-coding
98.5%
