Cell division schematic illustration

Figure 11.10 Protein expression inside the liposomes a working plan. Schematic illustration of two critical steps on the road map to the minimal cell (a) Protein expression of a simple protein (GFP) or any other simple protein and (b) protein expression of the enzymes that catalyze the formation of the vesicle boundary. For the sake of simplicity, growth and division is illustrated as an ideal duplication.

The process of cell division is a nice example of many of these motors working together. Figure 3 illustrates this in a simple schematic. Here, from the parent cell (A), duplication of the centriole occurs (B), and the centrioles migrate to opposite ends of the cell (C). Chromosome duplication and condensation follow (D), the nuclear envelope breaks down, and the two sets of chromosomes are drawn to the centrioles at opposite ends of the cell (E). Cell cleavage then takes place (F and G), and two... 

Fig. 3. Schematic illustrations of distinct steps in cell division show the central role of contractile motor action in the process of mitosis. (A) to (C) replication (prophase) (D) formation of the mitotic spindle (metaphase) (E) and (F) chromosome migration (anaphase) and building of the nuclear envelopes, and (G) formation of the contractile ring containing actin and myosin, forming the cleavage furrow and eventually two separate daughter cells. CE, centriole pair A, aster of microtubules N, nucleus M, microtubules C, chromosomes K, kinetochore NR, remnant of nuclear envelope NE, nucelar envelope reforming CR, contractile ring CM, cell membrane]. From Squire (1986).

The basic partitioning is illustrated schematically in Fig. 8a and realistically in Fig. 8b for a simulation study focusing on the dynamics of a tryptophan ring in the protein lysozyme.108 With the division indicated in the figure the total number of atoms to be simulated is 696 (294 protein atoms and 134 water molecules). This is a great reduction from the estimated 11,766 atoms (1266 protein atoms and 3500 water molecules) that would be necessary if conventional periodic boundary conditions were employed the estimate is based on using a 50-A cubic cell, a 26-A sphere to represent lysozyme, and 1 g/cm3 density for water. 

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