|
|
Mitochondrial protein import.
Drašnarová, Zuzana ; Doležal, Pavel (advisor) ; Pyrih, Jan (referee)
Most of mitochondrial proteins are synthesized in the cytoplasm and after that transported to the outer or the inner membrane or to the intermembrane space and the mitochondrial matrix. All mitochondrial proteins cross the outer membrane via the TOM complex. From here different populations of proteins follow distinct transport routes: (i) β-barel proteins are assembled in the outer membrane with the help the SAM complex, (ii) after the passage through the TOM complex the intermembrane space proteins are bound by the MIA pathway, (iii) the mitochondrial carrier proteins of the inner mitochondrial membrane require the activity of the TIM22 complex and finally (iv) the matrix proteins as well as the small sub-population of the inner membrane proteins are transported via the TIM23 complex. Whereas the transport across the outer mitochondrial membrane does not require the additional energy, the transport across the inner membrane depends on ATP and/or the membrane potential. The transported proteins carry targeting sequences which are recognized by the outer membrane receptors. Key words: protein import, mitochondria, translocase, membrane, matrix, intermembrane space
|
|
| |
|
|
Introduction of APEX-based labeling for the research of mitochondrial organelles of Giardia intestinalis and Trichomonas vaginalis.
Drašnarová, Zuzana ; Doležal, Pavel (advisor) ; Rothová, Olga (referee)
Giardia intestinalis and Trichomonas vaginalis are parasitic protists living in the environment without oxygen. For this reason, their mitochondria were transformed into organelles lacking the oxidative phosphorylation. We do not know anything about the intermembrane space (IMS) of these mitochondrial organelles. Main reason is that it is hard to isolate IMS proteins using the classical methods of the molecular biology, as cell fractionation. Recently, the new ascorbate peroxidase (APEX) tag has been developed. This tagging is suitable for the fluorescence as well as the electron microscopy. APEX can also behave like biotin ligase when exposed to biotin-phenol and this allows the labeling of the proteins of the compartment as well as their isolation. We optimized the conditions for optimal APEX activity and using this technique we were able to visualize the IMS of hydrogenosomes of T. vaginalis and to isolate hydrogenosomal proteins.
|
|
|
Mitochondrial protein import.
Drašnarová, Zuzana ; Doležal, Pavel (advisor) ; Pyrih, Jan (referee)
Most of mitochondrial proteins are synthesized in the cytoplasm and after that transported to the outer or the inner membrane or to the intermembrane space and the mitochondrial matrix. All mitochondrial proteins cross the outer membrane via the TOM complex. From here different populations of proteins follow distinct transport routes: (i) β-barel proteins are assembled in the outer membrane with the help the SAM complex, (ii) after the passage through the TOM complex the intermembrane space proteins are bound by the MIA pathway, (iii) the mitochondrial carrier proteins of the inner mitochondrial membrane require the activity of the TIM22 complex and finally (iv) the matrix proteins as well as the small sub-population of the inner membrane proteins are transported via the TIM23 complex. Whereas the transport across the outer mitochondrial membrane does not require the additional energy, the transport across the inner membrane depends on ATP and/or the membrane potential. The transported proteins carry targeting sequences which are recognized by the outer membrane receptors. Key words: protein import, mitochondria, translocase, membrane, matrix, intermembrane space
|
guest ::
