Characterization of the mRNA untranslated regions [UTR] of the Trypanosoma cruzi LYT1 isoforms derived by alternative trans-splicing

Abstract

In trypanosomatids,geneexpressionismainlyregulated at posttranscriptional level,throughmechanisms based on the interaction between RNA Binding Proteins [RBPs] and motifs present in the untranslated regions [UTRs] of Them RNAs,whichaltogetherformribonucleoproteiccomplexes [RNP] that define thefateofthemRNA.Thepre-mRNAderivedfromthe LYT1 gene of Trypanosomacruzi, isprocessedbyalternative trans-splicing, resultingin differentmRNAswhichcodefortheisoformsmLYT1andkLYT1,proteins having differential expression,cellular location and function.The aim of this study was to characterizethe5¿and3¿UTRsofthe LYT1 mRNAsasthe initial steptowardstheobjectiveofidentificationoftheRBPsresponsiblefor theirdifferentialexpression.Thepresenceofthetwotypesof5¿UTRswere confirmedintwo T.cruzi isolatesbelongingtotheDTUI,thus,corroborating theoccurrenceofalternative trans-splicing alsointhe LYT1 geneofthis T.cruzi DTU.Inaddition,forthefirsttime,wasunscoveredtheexistenceoftwo types of LYT1 mRNAstranscripts,differinginlengthby116nts,thatare generatedbyalternativepolyadenylation.Furthermore,an in-silico analysis of theexperimentallyobtainedUTRs,andtenadditional LYT1 sequences retrievedfromTritrypDBandGenBankdatabases,togetherwithathoroughly searchofstructuralmotifs,showedaremarkableconservationofrelevant structuralmotifspreviouslyassociatedwithRNAmetabolisminthedifferent UTRs; theseelementsmightbeinvolvedinthedifferentialstage