The biogenesis of organelles ensures propagation through successive generations but our knowledge of the underlying mechanisms is patchy, especially for membrane-bound organelles such as the Golgi apparatus. There are two popular models. The first considers the Golgi to be an autonomous organelle, responsible for its own duplication and partitioning during mitosis. This is the model we favor. The second model considers the Golgi to be a dependent organelle, in dynamic steady state with the ER, and reliant on it for all aspects of biogenesis. In the last granting period we studied those proteins that tether vesicles to Golgi membranes and cisternal membranes to each other. Collectively, we termed these matrix proteins and were able to provide evidence that they constituted an underlying scaffold that is normally populated by enzyme containing membranes. In this renewal we aim to confirm and extend these observations, focusing on the GRASP family of stacking proteins.
Our aim i s to determine precisely how these proteins carry out their stacking function. We also want to understand the process of Golgi assembly, both at the end of mitosis when the partitioned Golgi is reassembled, and during subsequent duplication, when a new copy of the Golgi is made. In particular we want to know whether the process is """"""""seeded"""""""" by matrix proteins and whether there is a precise order of cisternal assembly. Lastly, we have begun to study the process of Golgi duplication in two protozoan parasites, Toxoplasma gondii, and Trypanosoma brucei. Both have a single Golgi apparatus, the duplication of which can be followed in real time using video fluorescence microscopy. These simple systems are also medically important. ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
2R01GM060478-05
Application #
6730742
Study Section
Cell Development and Function Integrated Review Group (CDF)
Program Officer
Shapiro, Bert I
Project Start
2000-01-01
Project End
2008-01-31
Budget Start
2004-09-01
Budget End
2005-01-31
Support Year
5
Fiscal Year
2004
Total Cost
$306,390
Indirect Cost
Name
Yale University
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
043207562
City
New Haven
State
CT
Country
United States
Zip Code
06520
Franklin, Joseph B; Ullu, Elisabetta (2010) Biochemical analysis of PIFTC3, the Trypanosoma brucei orthologue of nematode DYF-13, reveals interactions with established and putative intraflagellar transport components. Mol Microbiol 78:173-86
de Graffenried, Christopher L; Ho, Helen H; Warren, Graham (2008) Polo-like kinase is required for Golgi and bilobe biogenesis in Trypanosoma brucei. J Cell Biol 181:431-8
Ang, Agnes Lee; Taguchi, Tomohiko; Francis, Stephen et al. (2004) Recycling endosomes can serve as intermediates during transport from the Golgi to the plasma membrane of MDCK cells. J Cell Biol 167:531-43
Shorter, James; Beard, Matthew B; Seemann, Joachim et al. (2002) Sequential tethering of Golgins and catalysis of SNAREpin assembly by the vesicle-tethering protein p115. J Cell Biol 157:45-62
Jokitalo, E; Cabrera-Poch, N; Warren, G et al. (2001) Golgi clusters and vesicles mediate mitotic inheritance independently of the endoplasmic reticulum. J Cell Biol 154:317-30
Pelletier, L; Jokitalo, E; Warren, G (2000) The effect of Golgi depletion on exocytic transport. Nat Cell Biol 2:840-6
Dirac-Svejstrup, A B; Shorter, J; Waters, M G et al. (2000) Phosphorylation of the vesicle-tethering protein p115 by a casein kinase II-like enzyme is required for Golgi reassembly from isolated mitotic fragments. J Cell Biol 150:475-88