Curiously, yeast mtRNase P function is impaired by disruption of the type II fatty acid synthesis (FAS II) pathway [73].
As in the Fas DD/FADD DD complex, disruption of the type IIa interface by the N150K mutation did not show a distinct effect on complex formation.
Consistently, homozygous disruption of the type II receptor of the TGF-β gene (Tgfbr2) in Apc1638N mice causes malignant transformation of the intestinal adenomas induced by Apc mutation [38].
This finding is consistent with the previous observation that disruption of the type IIb interface on Fas DD did not block formation of the Fas DD/FADD DD complex.
The balance between cell proliferation and cell death is important to maintain equilibrium in different tissues, and a disturbance in this balance may lead to tumour development [ 34] since the disruption of this type of regulation is a characteristic of tumours.
Although specific mutations of the p53 protein have been described in approximately 50% of human cancers, a disruption of wild-type p53 transcriptional activity can independently contribute to tumourgenesis in other cancer types (Chene, 2004; Haupt and Haupt, 2004; Tovar et al, 2006).
One report describes that in different cultured fibroblast cell lines, disruption of wild-type p53 function resulted in increased sensitivity of cells to taxol treatment compared to cells expressing wild-type p53 (Wahl et al, 1996).
For example, osteoblast-specific disruption of BMP type-IA receptor leads to LBM in young mice but HBM in old mice [64].
In the wing, expression of hINSC96Y leads to ectopic expression of veins and mechano-sensory organs, indicating disruption of wild-type signaling processes regulating cell fates.
The mutant transgene was able to accelerate tumor development in wild-type and Trp53+/- mice but had no effect in Trp53-/ mice, indicating its tumor promotion occurred only through disruption of wild-type p53 function [ 25].
