microRNA2

MicroRNA-2 refers to a member of the miR-2 family, small non-coding RNAs about 22 nucleotides in length. They regulate gene expression post-transcriptionally by pairing with target mRNAs, typically in the 3' untranslated region (3' UTR), guiding the RNA-induced silencing complex to repress translation or promote mRNA decay.

Biogenesis begins with transcription by RNA polymerase II to form a primary miRNA (pri-miRNA), which is processed by the Drosha-DGCR8 complex into a precursor miRNA (pre-miRNA) hairpin in the nucleus. The pre-miRNA is exported to the cytoplasm by exportin-5 and further processed by Dicer into a mature miRNA duplex. One strand is incorporated into the RNA-induced silencing complex (RISC); the guide strand of miR-2 typically directs repression of target mRNAs through seed matching (positions 2–8) in their 3' UTR, leading to translational repression and/or deadenylation and decay of the transcript.

In various species, miR-2 family members participate in neuronal development and differentiation, apoptosis, and patterning, with targets that differ across organisms. The functional outcomes depend on cellular context and the specific gene set regulated by the miR-2 member present. Some miR-2 family members have been explored in cancer models as potential oncogenic or tumor-suppressive regulators, depending on their targets.

In research contexts, microRNA-2 is studied using sequencing, quantitative PCR, Northern blotting, and luciferase reporter assays to confirm targets. Target prediction tools and cross-species conservation analyses aid in identifying candidate genes, while genetic manipulation in model organisms provides functional insight. Because miR-2 denotes a family with species-specific members, precise sequence, genomic location, and targets must be verified in organism-specific databases.