microRNA (miRNA)
Definition
Small non-coding RNA molecules of approximately 18-24 nucleotides that regulate gene expression post-transcriptionally. Abundant in blood cells, relatively resistant to degradation compared with full-length mRNA, and detectable by PCR assays with high sensitivity.
Related terms
- Degradation index
- A ratio or combination of RNA abundance measurements designed to capture the state of degradation of a sample. Often calculated as the...
- Inter-individual variability
- Differences in RNA degradation rate between different donors' blood, arising from variation in RNase activity, blood cell composition, and haematological status. One...
- mRNA (messenger RNA)
- Transcripts encoding proteins, synthesised in the nucleus from DNA templates and translated by ribosomes. mRNA molecules vary greatly in length (hundreds to...
- RNase
- Ribonuclease enzymes that cleave RNA phosphodiester bonds. Present in blood plasma (RNase A family) and released from cells on death. The activity...
- RT-qPCR
- Reverse-transcription quantitative PCR: a two-step assay in which RNA is first converted to complementary DNA (cDNA) by reverse transcriptase, then amplified and...
Explained in
- mRNA and microRNA Approaches to Stain AgeSmall non-coding RNA molecules of approximately 18-24 nucleotides that regulate gene expression post-transcriptionally. Abundant in blood cells, relatively res...