It is clear that membrane trafficking is active during cytokinesis which probably begins from early anaphase. What Tommy claimed is the membrane trafficking is active in mitosis.
One reason people don't believe Tommy's idea is many internal membrane organelles are disasembled during mitosis. Even there are some endocytosis activities, it is probably not a "general" endocytosis.
Pictures below are the results from my previous experiments which I treated cells with N-N-dimethylformamide for a short period of time to interrupt the association between membrane and cortical actin network. Membrane was released from the cortex as hugh blebs. Red is RhoA, green is actin, and blue is DNA. You will be surprised how much membrane can be stored on the rigid, round-up cortex, Same as cytokinetic cells.
M Phase Cell
C Phase Cell
Therefore I doubt cells require membrane trafficking to regulate the total amount of cortical membrane during cell division.
Another possiblity is membrane trafficking actually is working on recycling signal molecules, but not membrane per se. I will buy this hypothesis. However, compared to cytokinetic cells which have a highly specialized equatorial cortex for cleavage furrow, the cortex in metaphase is kind of homogenous. I just cannot see what can be recycled from mitotic cortex.
Together, I am still not convinced.
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