Proliferative genes

Proliferative genes are proto-oncogenes mutated proto-oncogenes may become oncogenes. 

Iwai, K., Hirata, K., Ishida, T, Takeuchi, S., Hirase, T., Rikitake, Y, Kojima, Y, Inoue, N., Kawashima, S. andYokoyama, M. (2004) An anti-proliferative gene BTGl regulates angiogenesis in vitro. Biochem. Biophys. Res. Commun. 516, 628-635. 

The screening method based on diameter of halos yielded only five strains with at least 20% more PG than wild t> e. Most attempts to enhance pectinase production have been made in filamentous fiingi, in which enzyme production is regulated by induction and catabolite repression mechanisms [8], By contrast, PG produced by marxianus is constitutive and not subject to catabolite repression [6], Failure to find greatly enhanced secretion levels is consistent with the idea of a constitutive gene that is capable of only modest further induction. PG was found in this study to be already the most prolific secreted protein of K. marxianus. 

Nasmyth The work by Gareth Williams and Ron Laskey with the MCM proteins in cervical cancer is an example of a cell cycle gene that is presumably part of some huge battery of genes that is somehow related to whether the cell is in a proliferative state. It turns out to be rather a good marker for tumour cells. But it is nothing directly to do with proliferation itself. 

The characterization of the cells isolated after transformation with a gene that alters the proliferative properties of the primary cells is approached at several different levels. The first stage is the verification that the cells are transformed and have altered growth properties when compared with primary cells. The next stage is the verification that the transformed cells are epithelial in origin. Finally, the cells can be characterized for specific genotypic and/or phenotypic endpoints that are of interest. 

Many intracellular targets of sphingosine that may contribute to its apoptotic and anti-proliferative effects have been identified (Figure 2). These include proteins of the bcl-2 family, the retinoblastoma gene product, several enzymes and its ability to interact with DNA (reviewed by Alessenko, 2000). For example, sphingosine-induced apoptosis of HL60 cells correlated with reduced expression of the cell survival protein bcl-2... 

Cyclosporin-A In 1972, the immunosuppressive effect of cyclosporin-A, an antibiotic secreted by some fungi, was discovered. Other antibiotics also have immunosuppressive effects. They interfere with proliferation of T-helper cells by preventing the entry of a transcription factor into the nucleus. This prevents transcription of the genes involved in the proliferative process. Their use is restricted to patients after transplantation, since there are serious side-effects, for example, toxic effects on the mbules of the kidney. This precludes their use for treatment of non-life-threatening autoimmune diseases. 

Retroviruses require proliferative target cells to mediate effective gene transfer. Lentiviruses, the class of retrovirus that includes human immunodeficiency virus, are an exception. They can also integrate in nondividing cells. An additional obstacle for retroviruses is the high susceptibility of the virus particle to humoral factors that ablate their gene transfer capacity. Perhaps most important, retroviruses, even when used ex vivo, pose a low but real risk of cancer. 

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