3'IsomiR Species Composition Affects Reliable Quantification of miRNA/isomiR Variants by Poly(A) RT-qPCR

Small RNA-sequencing (small RNA-seq) has revealed the presence of small RNA-naturally occurring variants such as microRNA (miRNA) isoforms or isomiRs. Due to their small size and the sequence similarity among miRNA isoforms, their validation by RT-qPCR is challenging. We previously identified two mi...

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Detalles Bibliográficos
Autores: Ferre-Giraldo, Adriana, Santiago, Lucía, Sánchez Herrero, José Francisco|||0000-0001-6771-4807, López-Rodrigo, Olga|||0000-0001-9325-5835, Sánchez-Curbelo, Josvany|||0000-0002-6489-3309, Sumoy, Lauro|||0000-0003-0005-4618, Bassas, Lluís|||0000-0002-3473-3611, Larriba, Sara|||0000-0003-4579-5452
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:300101
Acceso en línea:https://ddd.uab.cat/record/300101
https://dx.doi.org/urn:doi:10.3390/ijms242015436
Access Level:acceso abierto
Palabra clave:IsomiRs
MiRNA isoforms
Poly(A)-RT-qPCR
Selective amplification
Small RNAseq validation strategy
Descripción
Sumario:Small RNA-sequencing (small RNA-seq) has revealed the presence of small RNA-naturally occurring variants such as microRNA (miRNA) isoforms or isomiRs. Due to their small size and the sequence similarity among miRNA isoforms, their validation by RT-qPCR is challenging. We previously identified two miR-31-5p isomiRs-the canonical and a 3'isomiR variant (3' G addition)-which were differentially expressed between individuals with azoospermia of different origin. Here, we sought to determine the discriminatory capacity between these two closely-related miRNA isoforms of three alternative poly(A) based-RT-qPCR strategies in both synthetic and real biological context. We found that these poly(A) RT-qPCR strategies exhibit a significant cross-reactivity between these miR-31-5p isomiRs which differ by a single nucleotide, compromising the reliable quantification of individual miRNA isoforms. Fortunately, in the biological context, given that the two miRNA variants show changes in the same direction, RT-qPCR results were consistent with the findings of small RNA-seq study. We suggest that miRNA selection for RT-qPCR validation should be performed with care, prioritizing those canonical miRNAs that, in small RNA-seq, show parallel/homogeneous expression behavior with their most prevalent isomiRs, to avoid confounding RT-qPCR-based results. This is suggested as the current best strategy for robust biomarker selection to develop clinically useful tests.