Alternative splicing control over naïve primed pluripotency

• Autores: Victoria Eugenia Rodríguez Vaello
• Directores de la Tesis: Manuel Irimia Martínez (dir. tes.)
• Lectura: En la Universitat de Barcelona ( España ) en 2020
• Idioma: español
• Tribunal Calificador de la Tesis: Thomas Graf (presid.), Jovita Mezquita Pla (secret.), Thorsten Boroviak (voc.)
• Programa de doctorado: Programa de Doctorado en Biomedicina por la Universidad de Barcelona
• Materias:
  • Ciencias de la vida
    • Biología celular
    • Biología molecular
• Enlaces
  • Tesis en acceso abierto en: TDX
• Resumen

  • A fundamental step in embryo development is the transition through pluripotency. There are two known sequential states of pluripotency termed naïve and primed pluripotency. Considerable efforts have been made to characterize these two cell identities using gene expression, protein, metabolic and epigenetic profiling; but the molecular program that drives the naïve-to-primed transition is still poorly understood. Alternative splicing (AS) is known to be regulated in stem cells to confer pluripotent cell identity but its role during the transition between naïve and primed pluripotency states remains largely unexplored. We performed deep coverage RNA sequencing on embryo-derived stem cell lines and identified over 700 splicing events that were differentially spliced between the two states. These events showed distinct genomic features and were also observed in vivo and in equivalent human pluripotency states. By differential gene expression analyses, we found two regulatory axes that contributed to shape the two AS landscapes: the Rbmx/RbmxL2 axis and the Rbm47/Esrp axis. We further performed a high-throughput screen to test the effect of 1,500 single knockdowns of RNA binding proteins and chromatin modifiers on naïve-to-primed AS switches. This led us to the identification of Qki as an additional master naïve-to-primed AS regulator. Functional assays showed that depletion of these splicing regulators affected the differentiation dynamics of embryonic stem cells. Overall, our results provide new insights into the regulatory networks governing naïve and primed pluripotency and the gain of differentiation potential.