Biology Reference
In-Depth Information
Table 15.6 The definition of the c-triad, assumed to be the necessary and sufficient condition for
cell life including morphogenesis (Ji and Ciobanu 2003)
C-Triad
Description
1.
Computation
Cells are evolutionarily programmed to express only those genes that
promote the survival of the organisms (of which they are parts) under
given environmental conditions
2.
Construction
Cells manufacture their structural components and intercellular messengers
before undergoing cell division, under the control of the environment
(through synchronic interactions) and the genome (through diachronic
interactions)
3.
Communication
Cells communicate synchronically with one another by exchanging
messenger molecules in order to cooperate to accomplish tasks beyond
the ability of individual cells
Computation
Construction
Communication
Fig. 15.9 A diagrammatic representation of the C-triad (Ji and Ciobanu 2003). The three
processes are postulated to be both necessary and sufficient
to account for the molecular
mechanisms underlying the life of the cell
describable in terms of an n-bit string of 1
0
s and 0
0
. Thus, the circles of the
TRAL model and hypercubes are mathematically equivalent or isomorphic. All
the cells (i.e., nodes), except the original cell at the center, are connected by
three links each forming a Y in the centrifugal direction (i.e., from the center
toward the periphery), reflecting the fact that one cell gives rise to two cells
with the precursor cell disappearing as the result of cell division.
6. Within any time period (e.g., an average cell cycle time), only one ring, that is,
the outermost ring, is present or realized with all the associated precursor rings
having disappeared into the past (unlike the real tree rings which accumulate).
7. The outermost ring is associated with a probability space erected perpendicular
to it to encode the probabilities of observing particular gene-activity states of
the cells on the ring determined by the current cellular environment, the gene-
activity states being represented by strings of 2n 1
0
s (a gene turned on) or 0
0
s
(a gene turned off).
8. The gene-activity state of a cell, in combination with the cell environment, is
thought to determine the three fundamental activities of the cell, that is,
computation, construction, and communication (see Table
15.6
and Fig.
15.9
).
9. Therefore, the shape or topology of the probability landscape (to be referred
to as the probability distribution function of cell states [PDFCS]) erected on
the outermost ring (which resembles the topology of a landscape) is determined
by both the current gene-activity states of the cells (which in turn determine
