Biology Reference
In-Depth Information
macroscopic structure (phenotype)
proteins
A
genes
macroscopic structure (phenotype)
the macroscopic state determines the
specific protein interactions
proteins
B
genes
F
IGURE
10. The contradiction in genetic determinism. A:
According to genetic
determinism, protein interactions determine the macroscopic state of cells (their
phenotype).
B:
It is this macroscopic state which forces the proteins to behave in
a specific way. Organization arises therefore from the phenotype (from the global
structure) and not from the genes (from the genotype) and proteins. This com-
pletely upsets the founding premise of genetics!
intrinsic molecular nature but on the global state of the cell, which
permits it to propagate along a specific pathway (Dumont
et al
.,
2002). Although this is very surprising in the context of the reduc-
tionist paradigm, this view is furthermore confirmed by a spec-
tacular experiment analysed by Soto and Sonnenschein (2006).
Erythropoietin (EPO) and prolactin receptors activate transduc-
tion pathways that have several proteins in common. If the normal
EPO receptor is replaced in erythroid cells by a prolactin receptor,
these cells differentiate into red blood cells when they are stimu-
lated by prolactin (Socolovsky
et al
., 1998). Prolactin therefore
induces the signal normally provided by EPO. This hormone does
not normally play any part in red blood cell differentiation, however.
