Micro RNA-Mediated regulation of the full-length and truncated isoforms of human neurotrophic tyrosine kinase receptor type 3 (NTRK 3)

Guidi, Mònica

Micro RNA-Mediated regulation of the full-length and truncated isoforms of human neurotrophic tyrosine kinase receptor type 3 (NTRK 3)

Document Type

Doctoral thesis
Published Version

Author

Guidi, Mònica

Director

Espinosa Parrilla, Yolanda
Estivill, Xavier

Publication Date

2009-01-13

Citation

Guidi, M. Micro RNA-Mediated regulation of the full-length and truncated isoforms of human neurotrophic tyrosine kinase receptor type 3 (NTRK 3). Universitat Pompeu Fabra; 2009. handle: http://hdl.handle.net/10803/7114

This citation was generated automatically.

Doctoral program

Programa de doctorat en Biomedicina

Abstract

Neurotrophins and their receptors are key molecules in the development of the nervous system. Neurotrophin-3 binds preferentially to its high-affinity receptor NTRK3, which exists in two major isoforms in humans, the full-length kinaseactive form (150 kDa) and a truncated non-catalytic form (50 kDa). The two variants show different 3'UTR regions, indicating that they might be differentially regulated at the post-transcriptional level. In this work we explore how microRNAs take part in the regulation of full-length and truncated NTRK3, demonstrating that the two isoforms are targeted by different sets of microRNAs. We analyze the physiological consequences of the overexpression of some of the regulating microRNAs in human neuroblastoma cells. Finally, we provide preliminary evidence for a possible involvement of miR-124 - a microRNA with no putative target site in either NTRK3 isoform - in the control of the alternative spicing of NTRK3 through the downregulation of the splicing repressor PTBP1.
Las neurotrofinas y sus receptores constituyen una familia de factores cruciales para el desarrollo del sistema nervioso. La neurotrofina 3 ejerce su función principalmente a través de una unión de gran afinidad al receptor NTRK3, del cual se conocen dos isoformas principales, una larga de 150KDa con actividad de tipo tirosina kinasa y una truncada de 50KDa sin dicha actividad. Estas dos isoformas no comparten la misma región 3'UTR, lo que sugiere la existencia de una regulación postranscripcional diferente. En el presente trabajo se ha explorado como los microRNAs intervienen en la regulación de NTRK3, demostrando que las dos isoformas son reguladas por diferentes miRNAs. Se han analizado las consecuencias fisiológicas de la sobrexpresión de dichos microRNAs utilizando células de neuroblastoma. Finalmente, se ha estudiado la posible implicación del microRNA miR-124 en el control del splicing alternativo de NTRK3 a través de la regulación de represor de splicing PTBP1.

Keywords

RISC complex, retinoic acid, renilla luciferase, real-time quantitative PCR, PTBP1, pri-miRNA, pre-miRNA, post-transcriptional regulation, piRNA, PicTar, pGL4.13, PCR, P-body, p75NTR, overexpression, NTRK3, NTRK2, NTRK1, non-coding RNAs, NGF, neurotrophin, neurotrophic signaling, neuronal differentiation, neurodevelopment, neuroblastoma, nervous system, mRNA, miRNA target prediction, miRNA profiling, miRNA mimic, miRNA microarray, miRNA inhibitor, miRanda, microRNA, microarray, luciferase assay, Ingenuity Pathway Analysis (IPA), heLa cells, gene silencing, gene regulation, full-length isoform (FL-NTRK3), firefly luciferase, ERK, disease, dicer, cancer development, BDNF, argonaute, alternative splicing, 3'UTR, RNAhybrid, RT-PCR, SH-SY5Y cells, siRNA, standard error, synaptic plasticity, target validation, TargetScan, transfection, translational repression, TrkA, TrkB, TrkC, truncated isoform (TR-NTRK3), tyrosine kinase (TK), western blot