Tesis doctoral de Yaiza Español Fernández
Cytosolic and mitochondrial translations systems are separately maintained in eukaryotes. In the specific case of the trypanosoma brucei mitochondrial translation system, aminoacyl-trna synthetases and trnas are encoded in the nucleus and their transit through the cytosol on their way to the mitochondria is necessary. the t. Brucei genome codes for two trnalys isoacceptors: trnalys uuu and trnalys cuu that are shared by the two translation machineries mentioned. Over the course of this work, it has been determined that although cytosolic and mitochondrial trnalys uuu populations are transcribed from the same nuclear gene, they present different features. The implications of those features in trna mitochondrial import are discussed. the t. Brucei genome codes for two proteins with predicted lysyllysrna synthetase activity, namely tbkrs-1 and tbkrs-2. Unlike other known krss, tbkrs-2 contains an intriguing carboxyterminal extension with no homology to any reported protein. Tbkrs-1 and tbkrs-2 aminoacylation activity has been analyzed both in vivo and in vitro, their functional localization has been elucidated and the role of the carboxyterminal on tbkrs-2 activity has been tested. Furthermore, tbkrs-2 mitochondrial import determinants and processing events undergone by tbkrs-2 upon mitochondrial import have been determined. Altogether the results obtained in this work reveal a novel mechanism which ensures the segregation of lysyltrna synthetase activities in t. Brucei. This mechanism involves an extra domain in tbkrs-2 that prevents the enzyme from being active in the cytosol
Datos académicos de la tesis doctoral «Characterization of the lysyl-trna synthetases from trypanosoma brucei«
- Título de la tesis: Characterization of the lysyl-trna synthetases from trypanosoma brucei
- Autor: Yaiza Español Fernández
- Universidad: Barcelona
- Fecha de lectura de la tesis: 15/12/2009
Dirección y tribunal
- Director de la tesis
- Lluís Ribas De Pouplana
- Tribunal
- Presidente del tribunal: ricard Albalat rodriguez
- ignacio Luque romero (vocal)
- (vocal)
- (vocal)