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| Untersuchte Arbeit: Seite: 3, Zeilen: 1-17 |
Quelle: Otte et al 1998 Seite(n): 1605, Zeilen: left col. 28-33; right col. 4ff |
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| [Insulin-like growth factor -II (IGF-II) is a small mitogenic peptide and is one of the most ubiquitous growth factors in the mammalian embryo, where it plays an] important role in regulating fetal growth. This was demonstrated when transgenic mice with a disrupted IGF-II gene showed fetal growth retardation. The IGF-II gene shows a complex structural organisation in all species analyzed. It consists of at least nine exons in man and sheep, and six exons in rat and mouse. Its expression is regulated in a developmental and tissue-specific manner, involving differential promoter usage and alternative splicing, as well as differential RNA processing site. Ability of translation of the different promoter transcripts is variable and growth-dependent, and the translated product is also subject to posttranslational modification. The IGF-II mRNA population originates from the use of four promoters in man and sheep and three promoters in rodents. During fetal life three promoters are active both in human and rodents, with promoter P3 in humans and promoter P3 in rodents (which corresponds to P4 in human) being predominantly used. Transcription from these promoters is repressed during adult life and a fourth promoter becomes activated in human liver. No homologue to human promoter P1 has been identified in rodents, but is present in the ovine and baboon IGF-II genes. Furthermore, imprinted antisense transcripts are expressed in the mouse IGF-II gene (Otte et al., 1998). | Insulin-like growth factor 2 (IGF2) is a small mitogenic peptide (1) and is one of the most ubiquitous growth factors in the mammalian embryo, where it plays an important role in regulating fetal growth. This was demonstrated when transgenic mice with a disrupted IGF2 gene showed retardation of fetal growth (2). [...]
The IGF2 gene shows a complex structural organisation in all species analysed. It consists of at least nine exons in man and sheep, and six exons in rat and mouse (5–13). Its expression is regulated in a developmental and tissue-specific manner (14), involving differential promoter usage and alternative splicing (15), as well as differential usage of an RNA processing site (16,17). Translatability of the different promoter transcripts is variable and growth-dependent (18–20) and the translated product is also subject to posttranslational modification (21). The IGF2 mRNA population originates from the use of four promoters in man and sheep (6,7,22–24) and three promoters in rodents (8,10,13). During fetal life three promoters are active both in human and rodents, with promoter P3 in humans and promoter P3 in rodents (which corresponds to P4 in human) being predominantly used. Transcription from these promoters is repressed during adult life and a fourth promoter becomes activated in human liver (22,23,25–27). No homologue to human promoter P1 has been identified in rodents, but is present in the ovine and baboon IGF2 genes (7,28). Furthermore, imprinted antisense transcripts are expressed in the mouse IGF2 gene (29). 1 Blundell,T.L. and Humbel,R.E (1980) Nature, 287, 781–787. 2 DeChiara,T.M., Efstratiadis,A. and Robertson,E.J. (1990) Nature, 345, 78–80. 5 Ikejiri,K., Wasada,T., Haruki,K., Hizuka,N., Hirata,Y. and Yamamoto,M. (1991) Biochem. J., 280, 439–444. 6 Holthuizen,P.R, van der Lee,F.M., Ikejiri,K., Yamamoto,M. and Sussenbach,J.S. (1990) Biochim. Biophys. Acta, 1087, 341–343. 7 Ohlsen,S.M., Lugenbeel,K.A. and Wong,E.A. (1994) DNA Cell. Biol., 13, 377–388. 8 Frunzio,R., Chiariotti,L., Brown,A.L., Graham,D.E., Rechler, M.M. and Bruni,C.B. (1986) J. Biol. Chem., 261, 17138–17149. 9 Soares,M.B., Turken,A., Ishii,D., Mills,L., Episkopou,V., Cotter, S., Zeitlin,S. and Efstratiadis,A. (1986) J. Mol. Biol., 192, 737–752. 10 Ueno,T., Takahashi,K., Matsuguchi,T., Endo,H. andYamamoto,M. (1987) Biochem. Biophys. Res. Commun., 148, 344–349. 11 Ikejiri,K., Ueno,T., Matsuguchi,T., Takahashi,K., Endo,H. and Yamamoto,M. (1990) Biochem. Biophys. Acta, 1049, 350–353. 12 Rotwein,P. and Hall,L.J. (1990) DNA Cell. Biol., 9, 725–735. 13 Ikejiri,K., Furuichi,M., Ueno,T., Matsuguchi,T., Takahashi,K., Endo,H. and Yamamoto,M. (1991) Biochim. Biophys. Acta, 1089, 77–82. 14 Rechler,M.M. and Nissley,S.P. Insulin-like growth factors. (1990) In Sporn,M.B. and Roberts,A.B. (eds), Peptide Growth Factors and their Receptors, New York: Springer-Verlag, pp 236–362. 15 Sussenbach,J.S., Steenbergh,P.H. and Holthuizen,P. (1992) Growth Regulation, 2, 1–9. 16 Christiansen,J., Kofod,M. and Nielsen,F.C. (1994) Nucleic Acids Res., 22, 5709–5716. 17 Scheper,W., Holthuizen,P.E. and Sussenbach,J.S. (1996) Nucleic Acids Res., 24, 1000–1007. 18 Nielsen,F.C., Gammeltolft,S. and Christiansen,J. (1990) J. Biol. Chem., 265, 13431–13434. 19 De Moor,C.M, Jansen,M., Sussenbach,J.S. and Van Den Brande,J.L. (1994) Eur. J. Biochem., 222, 1017–1024. 20 Nielsen,F.C., Ostergaard,L., Nielsen,J. and Christiansen,J. (1995) Nature, 377, 358–362. 21 Daughaday,W.H. and Rotwein,P. (1989) Endocrine Rev., 10, 69–91. 22 de Pagter-Holthuizen,P., Jansen,M., van Schaik,F.M., van der Kammen,R., Oosterwijk,C., Van Den Brande,J.L. and Sussenbach,J.S. (1987) FEBS Lett., 214, 259–264. 23 de Pagter-Holthuizen,P., Jansen,M., van der Kammen, R.A., van Schaik,F.M. and Sussenbach,J.S. (1988) Biochim. Biophys. Acta, 950, 282–295. 24 Newell,S., Ward,A. and Graham,C. (1994) Mol. Reprod. Dev., 39, 249–258. 25 Schofield,P.N. and Tate,V.E. (1987) Development, 101, 793–803. 26 van Dijk,M.A., van Schaik,F.M., Bootsma,H.J., Holthuizen,P. and Sussenbach,J.S. (1991) Mol. Cell. Endocrinol., 81, 81–94. 27 Li,X., Cui,H., Sandstedt,B., Nordlinder,H., Larsson,E. and Ekstr¨om, T.J. (1996) J. Endocrinol., 149, 117–124. 28 Jin,I.H., Sinha,G., Yballe,C., Vu,T.H. and Hoffman,A.R. (1995) Horm. Metab. Res., 27, 447–449. 29 Moore,T., Constanzia,M., Zubair,M., Bailleul,B., Feil,R., Sasaki,H. and Reik,W. (1997) Proc. Natl. Acad. Sci. USA, 94, 12509–12514. |
Although the source is finally given none of this has been marked as a citation. All of the original references have been omitted |
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