Proto-oncogene products

The relationship between the two receptors for NGF is complex and not yet completely understood. It has been suggested that the functional form of the NGF receptor is a heterodimer of p75 and pl40 proteins. BDNF and NT-3 bind to p75, but the functional receptors for these neurotrophins are the proto-oncogene products of and trkQ. 

Sagata, N., Oskarsson, M., Copeland, T Brumbaugh, J and Vande Woude, G. F. (1988). Function of c-mos proto-oncogene product in meiotic maturation in Xenopus oocytes. Nature 335 519-525. 

Paules, R. S., Buccione, R., Moschel, R. C., Vande Woude, G. F., and Eppig, J. J. (1989). Mouse mos proto-oncogene product is present and functions during oogenesis. Proc. Natl. Acad. Sci. USA 86 5395-5399. 

Andoniou, C. E., et al.. The Cbl proto-oncogene product negatively regulates the Src-family tyrosine kinase Eyn by enhancing its degradation. Mol Cell Biol, 2000, 20(3), 851-67. 

Meisner, H., and M. P. Czech. Coupling of the proto-oncogene product c-Cbl to the epidermal growth factor receptor. J Biol Chem. 270 25332-25335.1995. 

A frequent cause of activation of proto-oncogenes is a change in the structure of the coded protein, affecting the regulation and function. Via the oncogenic activation, there is no creation of completely new functions, but rather the normal function of a proto-oncogene product is modified and/or released from cellular regulation. 

A change in the gene expression or stability of a proto-oncogene product may lead to an increase in the cellular concentration of the protein. Due to the increased concentration, a mitogenic signal mediated by a proto-oncogene product may be amplified. 

Paz-Ares, J., Goshal, D., Wienand, U., Peterson, P. A., and Saedler, H., 1987, The regulatory cl locus of Zea mays encodes a protein with homology to myb proto-oncogene products and with structural similarities to transcriptional activators, EMBO J. 6 3553-3558. 

Matsuda, S., Kadowaski, Y., Ichino, M., Akiyama, T., Toyoshima, K., and Yamamoto, T. 1993. 17/3-Estradiol mimics ligand activity of c-erbB2 proto-oncogene product. Proc. Natl. Acad. Sci. USA 90 10803-10807. 

Wrba, F., Gullick, W. J., Fertl, H. et al. 1989. Immunohistochemical detection of the c-erbB-2 proto-oncogene product in normal, benign and malignant cartilage tissues. Histopathology 75 71-76. 

CiCHOWSKI K, Brugge JS, Brass LF. Thrombin recq>tor activation and integrin engagement stimulate tyrosine phospheaylalion of the proto-oncogene product, p95 , in platelets. JBiol Chem 271 7544-7550,19%. 

Crespo P, SCHUEBEL KE, Ostrom AA, GUTKIND JS, BUSTELO XR. Phosphotyrosine-dependent activation of Rac-l GDP/GTP exchange by the vav proto-oncogene product. Muure 385 169-172,1997. 

DECKERT M, TARTARE-DECKERT S, Couture C, MUSTELIN T, Altman A. Functicmal and physical interactions of Syk family kinases with the Vav proto-oncogene product Immunity 5 591-604,1996. 

Margolis B, Hu P, Katzav S, Li W, Olivhi JM, Ullrich A, Weiss A, Schlessingsi J. Tyrosine phosphorylation of vav proto-oncogene product containing SH2 domain and transcription factor motifs Nature 356 71-74,1992. 

O Neill E, Rushworth L, Baccarini M, Kolch W (2004) Role of the kinase MST2 in suppression of apoptosis by the Proto-Oncogene product Raf-1. Science 306 2267-2270... 

A EXPERIMENTAL FIGURE 23-18 Addition of serum to quiescent 3T3 cells yields a marked increase in the activity of two proto-oncogene products, c-Fos and c-Myc. Serum contains factors like platelet-derived growth factor (PDGF) that stimulate the growth of quiescent cells. One of the earliest effects of growth factors is to induce expression of c-fos and c-myc, whose encoded proteins are transcription factors. 

Kaplan, D.R., Martin-Zanca, D. and Parada, L.F. (1991) Tyrosine phosphorylation and tyrosine kinase activity of the trk proto-oncogene product induced by NGF. Nature 350 158-160. 

Like insulin, the intracellular portion of the plasma membrane receptor for lGF-1 (but not lGF-11) has intrinsic tyrosine kinase activity. The fact that the receptors for insulin and a number of other growth factors have intrinsic tyrosine kinase activity indicates that tyrosine phosphorylation initiates the process of cellular replication and growth. Subsequently, a chain of kinases is activated, which include a number of proto-oncogene products (see Chapters 11 and 18). 

Mature mRNA molecules vary in lifetime. Some last for hours or days. Among the latter are mRNAs of maternal origin that accumulate in oocytes and are utilized during the early stages of embryonic development. Other mRNAs, e.g., transcripts of the c-fos and c-myc proto-oncogene products, have half-lives of 30 Some mRNA molecules are... 

Kaplan, D., et al.. The trk proto-oncogene product a signal transducing receptor for nerve growth factor. Science, 1991, 252, 554-557. 

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