microRNA let-7i-5p (let-7i-5p)

microRNA let-7i-5p is a highly conserved member of the let-7 family of small non-coding RNAs, which are critical regulators of gene expression at the post-transcriptional level (1.2.1, 1.2.3). It functions primarily by binding to the 3-untranslated regions (3-UTRs) of target messenger RNAs (mRNAs), leading to their degradation or the inhibition of their translation into proteins (1.1.1, 1.2.4). In many contexts, let-7i-5p acts as a tumor suppressor by downregulating key oncogenes such as RAS, HMGA2, and MYC, thereby inhibiting cell proliferation and promoting apoptosis (1.2.2, 1.2.5). However, its role is context-dependent, and it has been observed to promote tumor progression in certain malignancies like nasopharyngeal carcinoma and clear cell renal cell carcinoma (1.2.3, 1.3.2). Beyond oncology, let-7i-5p is involved in regulating inflammatory responses, cardiovascular health, and neuroprotection, often through its presence in mesenchymal stem cell-derived exosomes (1.1.1, 1.1.2). Therapeutic development focuses on using miRNA mimics to restore its expression in cancers where it is lost, or antisense inhibitors (antagomirs) to block its activity in conditions where it is pathologically upregulated (1.2.1, 1.2.2).

Other names

hsa-let-7i-5pMIR7IMIRNLET7Ilet-7i

Binds to the 3-untranslated region (3-UTR) of target mRNAs to induce translational repression or mRNA degradation; also modulates DNA methylation and chromatin conformation.