Analysis of the expression, function, and evolution of miR-27 isoforms and their responses in metabolic processes

Abstract

This study aimed to discuss the potential roles of isomiRs of miR-27 family in metabolisms associated with disease via analyses of their evolution, expression, and function. miR-27b-3p was relatively highly expressed in liver cancer samples compared to miR-27a-3p and miR-27-5p loci. The diversity of isomiRs in miR-27-3p locus is similar to that of miRNAs among homologous genes. IsomiRs exhibited variable expression across different cancer tissue types, and some of them were abnormally expressed in ob/ob mice. Further experimental validation indicated that the protein expression of metabolism-related proteins, including PEPCK, G6Pase, FAS, and CPT1A, were significantly suppressed when canonical miR-27b was transfected into AML-12 cells. In contrast, the expression of these proteins was only slightly inhibited by isomiR-27b-1 or isomiR-27b-2 after transfection into AML-12 cells. These observations support that isomiRs exhibiting sequence divergence are functional regulatory molecules, and that they may contribute to biological processes via coordinated interactions in regulatory networks.

Circulating microRNA/isomiRs as novel biomarkers of esophageal squamous cell carcinoma

“…Of note, these previous reports dealt with the mature miR-205-5p and miR-574-3p whereas our diagnostic panel included isomiR. The two types were previously thought to have a similar function because of their similar sequence, but more recent studies have identified that they have different functions [19,43,44]. In fact, the target messenger RNA of isomiR has concordance and discordance with mature miR, in accordance with the difference between them in sequence [45].…”

MicroRNA-27a (miR-27a) in Solid Tumors: A Review Based on Mechanisms and Clinical Observations

“…In liver cancer, miR-27a-3p has a high expression level of isomiR in normal cells, while isomiR expression is decreased significantly in tumor cells. However, this differentiation is not observed at the homologous miR-27b-3p site, indicating that isomiR-27a may have a more complicated background in tumor cells (20). As a 22-nt long mimic, it is easy for miR-27a to cooperate with other miRs.…”

MiR‐27 alleviates myocardial cell damage induced by hypoxia/reoxygenation via targeting TGFBR1 and inhibiting NF‐κB pathway

“…The miR-27 family (containing miR-27a and miR-27b), a highly conserved miRNA family across different species, are encoded on different chromosomes and share analogous seed sequences with a nucleotide difference at the 3 0 end. 13 Recent research has suggested that miR-27a can increase the expression of β-MHC gene in ventricular myocytes. 14…”