ER compartmentalization

The secretory membrane system in the Drosophila syncytial blastoderm embryo exists as functionally compartmentalized units around individual nuclei

David Frescas, Manos Mavrakis, Holger Lorenz, Robert DeLotto, and Jennifer Lippincott-Schwartz

J. Cell Biol. 2006 173: 219-230.

A very simple question was addressed in this work. Is the ER and Golgi compartmentalized in the Drosophila syncytial blastoderm embryo? The answer is NO and YES. NO, if nuclei are still in the interior of the embryo, and YES, if the nuclei are already in the periphery of the embryo. The authors also found that the compartmentalization is disrupted when microtubules are depolymerized after the nuclei arrived to the periphery. Also this compartmentalization occurs prior to cellularization, suggesting a role for the microtubule cytoskeleton on the formation of distinct ER and Golgi compartments within the same space.
Now the question is what are the mechanisms that give rise to this compartmentalization.

note: during proof reading of this post, a comment on the same paper was published in this blog by the mad scientist. Any similarities between posts is a pure coincidence and should not be use against the authors of this blog.