Spindle-Localized CPE-Mediated Translation Controls Mediotic Chromosome Segregation
- Autores: Carolina Eliscovich
- Directores de la Tesis: Raúl Méndez de la Iglesia (dir. tes.)
- Lectura: En la Universitat Pompeu Fabra ( España ) en 2008
- Idioma: español
- Materias:
- Enlaces
- Tesis en acceso abierto en: TDX
- Resumen
Meiotic progression and early development are programmed, at least in part, by the translational activation of maternally inherited mRNAs, such as the ones encoding for cyclin B1 or mos. These mRNAs are not translated en masse at any one time, or even at any one place; rather, their translation is specifically regulated by the cytoplasmic polyadenylation element (CPE) present in their 3'UTRs, which recruits the CPE-binding protein CPEB (Colegrove-Otero et al., 2005; de Moor et al., 2005; Mendez and Richter, 2001; Richter, 2007). This RNA-binding protein not only dictates the timing and extent of translational activation by cytoplasmic polyadenylation (Mendez et al., 2000a; Mendez et al., 2000b; Mendez et al., 2002) but also participates, together with the translational repressor Maskin, in the transport and localization, in a quiescent state, of its targets to the subcellular locations where their translation is going to take place (Huang et al., 2003; Huang and Richter, 2004). During Xenopus early development, CPEB localizes at the animal pole of oocytes and later on embryonic spindles and centrosomes (Groisman et al., 2000). Disruption of embryonic CPEB-mediated translational regulation results in abnormalities in the mitotic apparatus and inhibits embryonic mitotic divisions (Groisman et al., 2000). In this thesis work we show that spindle-localized translational activation of CPE-regulated mRNAs, encoding for proteins with a well-known function in the structural aspects of the cell cycle namely spindle assembly and chromosome segregation, is essential to complete the first meiotic division and for chromosome segregation in Xenopus oocytes.
