mmu-mir-1224: Mmu-mir-1224 is a canonical mirtron with the guide strand in the 5′ arm that has been shown to be functional against reporter targets in the 3′ untranslated region (3′ UTR) of Renilla luciferase [PMC4513878]. It has been found to be upregulated in Kupffer cells [PMC7766432]. Mmu-mir-1224 mimic was used in transfection experiments using DharmaFECT 1 transfection reagent [PMC9868883]. Mutations made to the splice sites of mmu-mir-1224 resulted in the abrogation of splicing and restoration of a functional eGFP mRNA transcript [PMC3479180]. Mmu-mir-1224 has been identified as a potentially attractive mirtron for targeting genes of interest [PMC3479180]. Removal of a secondary structure bulge in mmu-mir-1224 affected its processing and silencing ability [PMC3479180]. Mmu-mir-1224 was found to be differentially expressed in both sexes induced by GR ablation, with its expression changing in opposite directions [PMC7906897]. It is one of several miRNAs that are upregulated during follicle atresia, while others are downregulated during this process [PMC9783981] [PMC6256094] [PMC4522283]. The mmu-mir-1224 mirtron loop sequence was used as the loop for artificial mirtrons due to its favorable branch point and splicing prediction scores during design analysis [PMC8307164]. Mmu-mir-1224 is one of several miRNAs expressed by Kupffer cells, along with mmu-mir-720p, mmu-miR-2141, and others [PMC8652219] The abundance of mmu-miR-1224 has been observed in fecal samples [PMC6599184].