Expression and Regulation Profile of Mature MicroRNA in the Pig: Relevance to Xenotransplantation

Abstract

The pig is an important source of meat production and provides a valuable model for certain human diseases. MicroRNA (miRNA), which is non-coding RNA and regulates gene expression at the posttranscriptional level, plays a critical role in various biological processes.Studies on identification and function of mature miRNAs in multiple pig tissues are increasing, yet the literature is limited. Therefore, we reviewed current research to determine the miRNAs expressed in specific pig tissues that are involved in carcass values (including muscle and adipocytes), reproduction (including pituitary, testis, and ovary), and development of some solid organs (e.g., brain, lung, kidney, and liver). We also discuss the possible regulating mechanisms of miRNA. Finally, as pig organs are suitable candidates for xenotransplantation, biomarkers of their miRNA in xenotransplantation were evaluated.

New long-non coding RNAs related to fat deposition based on pig model

“…For lncRNA-miRNA, the following default parameters were used: minimum seven base pairs in seed, no lonely base pairs, no GU at helix ends, ignore seeds with GU ends, maximum interaction energy of -15 kcal/mol and hybridisation energy of -16.5 kcal/mol. As input miRNA data, the DE miRNA sequences (including isomiRs) identified in our previous study (GSE122816) were used (Ropka-Molik et al, 2020), along with fat-related miRNA sequences mentioned in the literature (Du et al, 2018;Iacomino and Siani, 2017;Song et al, 2018;Zhu et al, 2018). For lncRNA-target_mRNA interaction analysis, the following default parameters were used: minimum 10 base pairs in seed, no lonely base pairs, no GU at helix ends, ignore seeds with GU ends, and threshold set at maximum interaction energy of -30 kcal/ mol and hybridisation energy -35 kcal/mol.…”

The potential role of 3D-bioprinting in xenotransplantation

“…mRNA from several endothelial cell lines revealed heterogeneous signatures even in passaged cells, providing evidence that epigenetic modification mediates differential gene expression (transcriptome) profiles ]. This heterogeneity and variable gene expression between cells reflects to two important phenomena in xenotransplantation research [30]; genetically engineered pigs produced by CRISPR/cas9 (clustered regularly interspaced short palindromic repeat/cas9) technology with knockout or knockin of genes (pig or human) may have different expression levels in different organs and tissues (D. Ayares, personal communication), and immunogenicity of different organs and tissues (such as aorta, kidney, lungs) from the same genetically engineered pig with similar gene transcription levels may respond differently to the same stimulant (recipient) (Ekser et al, unpublished data).…”