Argonaute 2 immunoprecipitation revealed large tumor suppressor kinase 1 as a novel proapoptotic target of miR‐21 in T cells. (6th February 2017)

• Record Type: Journal Article
• Authors: Teteloshvili, Nato; Smigielska‐Czepiel, Katarzyna; Yuan, Ye; Seitz, Annika; de Jong, Debora; Rutgers, Bea; Jellema, Pytrick; van der Lei, Roelof Jan; Slezak‐Prochazka, Izabella; Brouwer, Elisabeth; Boots, Annemieke M.H.; Kroesen, Bart‐Jan; van den Berg, Anke; Kluiver, Joost
• Is Part Of: FEBS journal. Volume 284:Number 4(2017)
• Page Start: 555
• Page End: 567
• Publication Date: 2017-02-06
• Subjects: AGO2‐RIP -- apoptosis -- LATS1 -- miR‐21 -- T cells; Biochemistry -- Periodicals; Molecular biology -- Periodicals; Pathology, Molecular -- Periodicals; 572
• DOI: 10.1111/febs.14011
• Languages: English
• ISSNs: 1742-464X

Abstract

Abstract : MicroRNA (miR)‐21 is an important suppressor of T‐cell apoptosis that is also overexpressed in many types of cancers. The exact mechanisms underlying the antiapoptotic effects of miR‐21 are not well understood. In this study, we used the Jurkat T‐cell line as a model to identify apoptosis‐associated miR‐21 target genes. We showed that expression of miR‐21 rapidly increases upon αCD3/αCD28 activation of Jurkat cells. Inhibition of miR‐21 reduced cell growth which could be explained by an increase in apoptosis. MicroRNA target gene identification by AGO2 RNA‐immunoprecipitation followed by gene expression microarray (RIP‐Chip) resulted in the identification of 72 predicted miR‐21 target genes that were at least twofold enriched in the AGO2‐IP fraction of miR‐21 overexpressing cells. Of these, 71 were at least twofold more enriched in the AGO2‐IP fraction of miR‐21 overexpressing cells as compared to AGO2‐IP fraction of control cells. The target gene for which the AGO2‐IP enrichment was most prominently increased upon miR‐21 overexpression was the proapoptotic protein LATS1. Luciferase reporter assays and western blot analysis confirmed targeting of LATS1 by miR‐21. qRT‐PCR analysis in primary T cells showed an inverse expression pattern between LATS1 transcript levels and miR‐21 upon T‐cell stimulation. Finally, LATS1 knockdown partially rescued the miR‐21 inhibition‐induced impaired cell growth. Collectively, these data identify LATS1 as a miR‐21 target important for the antiapoptotic function of miR‐21 in T cells and likely also in many types of cancer. Abstract : MicroRNA (miR)‐21 is an important suppressor of T‐cell apoptosis, but the relevant targets of miR‐21 have remained unclear. By performing RNA‐immunoprecipitation followed by gene expression microarray (RIP‐Chip), Kluiver and colleagues now find that LATS 1, which encodes a pro‐apoptotic protein in the Hippo signalling pathway, is a miR‐21 target. T‐cell activation increased miR‐21 levels, which correlated with a reduction in LATS1 levels. Depletion of miR‐21 in T cells induces apoptosis; however, concomitant LATS 1 knockdown partially rescued this effect. This study suggests that LATS 1 is a key target for the anti‐apoptotic function of miR‐21 in T cells.