MINIATURE INVERTED?REPEAT TRANSPOSABLE ELEMENTS (MITES) ARE RELATED TO MICRORNA PRODUCTION SITES AND TARGETS GENES IN WHEAT

CRESCENTE J. M.; GUIDOBALDI F.; HELGUERA M.; VANZETTI L. S.

Rosario

Simposio; Simposio de Genómica Funcional de Plantas; 2017

Through a computational approach we have identified high-confidence putative 21-nt microRNA (miRNA) production sites and predicted cleavage-directed target genes. These miRNA production sites are expected to emerge from MITEs insertions, specifically in intronic regions or untranslated regions (UTR). 21nt filtered miRNA library consist in 581.178 sequences. This was aligned against 15.218 scaffolds (65 Mb) throwing 28.582 perfect match hits. From those results, 7.579 regions could develop a pre-miRNA-like hairpin structure according to UNAfold. After extracting annotation for these sections, we determined that 2.462 come from either intronic or UTR regions. The transcription strand validation shows that 1.356 of the results could possibly be transcribed in pre-miRNAs with correct orientation. Cleavage analysis performed with degradome library shows evidence that sliced targets hits 58 transcripts. Comparing the 1.355 miRNA production sites with known transposable elements gave 728 positive results. According to detectMITE, from the remaining 627 negative results, 268 have the structure of a MITE (TSD, TIR and high copy number), showing that 73% of miRNA production sites is TE-related and giving strong evidence that miRNA can be produced by a MITE insertion