They showed that the division of these stem cells is regulated at the final stage of replication, called cytokinesis, right before the two
daughter cells separate.
Bellen's research team have discovered that the Arp2/3 complex and its activator WASp (Wiskott-Aldrich syndrome protein) function in these
daughter cells to transport Delta vesicles to the apical region of the
daughter cells.
Caption: A young brain stem cell (shown dividing, top) packs old proteins (red) into a
daughter cell. Older cells (one shown, bottom) lose a barrier that segregates these proteins.
The word "epigenetic" literally means "in addition in changes in generic sequence." The term has evolved to include any process that alters gene activity without changing the DNA sequence, and leads to modifications that can be transmitted to
daughter cells (although experiments show that some epigenetic changes can be reversed).
During early development, the following common features were apparent: (1) the first cell division produces prospective cells that generate the anterior peripheral region of the embryo; (2) the second cell division produces prospective cells that generate the posterior peripheral region plus the internal cells of the embryo; (3) in the lineage of prospective internal cells, several divisions ultimately result in cell death of one of the
daughter cells. Early developmental processes are almost identical in the vermiform embryos of all four dicyemid genera.
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Daughter Cell (Sequel to The Chosen) by Jay Hartlove
2 HEALTHY DAUGHTERS Protein structures called kinetochores (red) are largely responsible for a crucial task: ensuring that each
daughter cell produced when a cell divides in two ends up with a complete set of chromosomes.
Specifically, when cells in culture were first treated with ethanol, the subsequent exposure to bad cholesterol was without effect on cell division: Each
daughter cell received the correct number of chromosomes.
coli bacteria dividing over hundreds of generations and confirmed that the sausage-shaped bacteria divided each time into
daughter cells that grew elongated at different rates -- suggesting that one
daughter cell was getting all or most of the cellular damage from its mother while the other was getting little or none.