K-fiber dynamics: a focus on the microtubule minus-ends
- Autores: Alejandra Laguillo Diego
- Directores de la Tesis: Isabelle Vernos (dir. tes.)
- Lectura: En la Universitat Pompeu Fabra ( España ) en 2021
- Idioma: español
- Tribunal Calificador de la Tesis: Jens Lüders (presid.), Thomas Surrey (secret.), Stefanie Redemann (voc.)
- Programa de doctorado: Programa de Doctorado en Biomedicina por la Universidad Pompeu Fabra
- Materias:
- Enlaces
- Tesis en acceso abierto en: TDX
- Resumen
During cell division, microtubules (MTs) organize into a bipolar spindle that drives faithful chromosome segregation through the kinetochore fibers (k-fibers), bundles of parallel MTs that attach the chromosomes through their plus-ends to the spindle poles through their minus-ends. K-fiber MT plus and minus ends dynamics are coordinated to provide stability at the same time as support error correction, chromosome alignment and segregation. However, k-fiber minus-ends have been poorly characterized.
Electron tomography studies showed that the k-fibers MT minus ends have mixed open or close conformations suggesting complex regulatory mechanisms. Consistently, the silencing of MCRS1, currently the only potential regulator, results in k-fibers with less MTs with an increased proportion of open ends morphologies. TIRF based in vitro reconstitution assays showed that MCRS1 and KANSL3 associate preferentially with one MT end. Another member of the complex, KANSL1 may mediate their interaction formation of a ternary complex. Altogether, my results suggest that the MCRS1-KANSL-complex could dynamically “cap” some K-fiber MT-minus-ends to regulate their depolymerization rates for proper cell division.
