IHEM   20887
INSTITUTO DE HISTOLOGIA Y EMBRIOLOGIA DE MENDOZA DR. MARIO H. BURGOS
Unidad Ejecutora - UE
artículos
Título:
Modeling fusion/fission-dependent intracellular transport of fluid phase markers
Autor/es:
MAYORGA, L.S.; CAMPOY, E
Revista:
TRAFFIC
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Año: 2010
ISSN:
1398-9219
Resumen:
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A fundamental feature of
eukaryotic cells is the presence of distinct membrane-bound compartments having
unique protein and lipid composition.
These compartments are interconnected by active trafficking mechanisms
that must direct macromolecules to defined locations, and at the same time
maintain the protein and lipid composition of each organelle. It is well
accepted that Rab proteins play a central role in intracellular transport
regulating the recognition, fusion and fission of organelles. However, how the transport is achieved is not
completely understood. We propose a model
whereby a soluble component in the luminal compartment is transported along
different Rab-containing organelles that interact according to the following
simple principles: i) only organelles with the same or compatible Rab membrane
domains can fuse, ii) after fusion, an asymmetric fission occurs producing a
tubule and a round-shaped vesicle, and iii) Rab membrane domains distribute
asymmetrically between the two resulting organelles. When this model was tested
in a simulation, efficient unidirectional transport was observed, while the
compartment identity was preserved. All three principles were absolutely
necessary for transport. The model is
compatible with Rab association/dissociation dynamics and with Rab conversion. In simulations mimicking a simplified
endocytic pathway, soluble and membrane-associated markers were efficiently
transported preserving the identity of the interacting compartments.