Identify at least different mutations that result in growth factor receptors that transform cells.
Identify at least different mutations that result in growth factor receptors that transform cells.
Solution
Mutations that result in growth factor receptors that transform cells:
1). The host cell-growth receptors can be activated upon the binding of certain virus-encoded
proteins. This results in uncontrolled cell proliferation in the absence of normal signals necessary
for cell proliferation.
2). Mutations that cause dimerization of tyrosine kinases result in constitutive activation of
receptors in the absence of normal cellular signals. A similar effect is observed if the growth
factor receptors are overexpressed.
3). Constitutive expression of intracellular signal-transduction proteins in the tumor cells allow
the growth enhancing signals in the absence of normal growth factors.
4). Point mutation in Ras, which reduces its GTPase activity and thus maintain it in an activated
state. Thus, the growth signals are continuously passed.
5). Abnormal expression of nuclear transcription factors including the Fos, Myc and Jun also
induce transformation..
Identify at least different mutations that result in growth facto.pdf
1. Identify at least different mutations that result in growth factor receptors that transform cells.
Identify at least different mutations that result in growth factor receptors that transform cells.
Solution
Mutations that result in growth factor receptors that transform cells:
1). The host cell-growth receptors can be activated upon the binding of certain virus-encoded
proteins. This results in uncontrolled cell proliferation in the absence of normal signals necessary
for cell proliferation.
2). Mutations that cause dimerization of tyrosine kinases result in constitutive activation of
receptors in the absence of normal cellular signals. A similar effect is observed if the growth
factor receptors are overexpressed.
3). Constitutive expression of intracellular signal-transduction proteins in the tumor cells allow
the growth enhancing signals in the absence of normal growth factors.
4). Point mutation in Ras, which reduces its GTPase activity and thus maintain it in an activated
state. Thus, the growth signals are continuously passed.
5). Abnormal expression of nuclear transcription factors including the Fos, Myc and Jun also
induce transformation.
