|
|
|
| Untersuchte Arbeit: Seite: 28, Zeilen: 1-45 |
Quelle: Boini 2006 Seite(n): 12, 14, 15, Zeilen: 12: 11ff; 14: 12ff; 15: 1ff |
|---|---|
| [Like SGK2, SGK3 has been implicated in the regulation of numerous] transporters and channels, including K+ channels (Gamper et al., (2002) Pflügers Arch; Henke et al., (2004) J cell Physiol); Embark et al., (2003) Pflügers Arch), Na+-K+-ATPase (Henke G. et al., (2002) Kidney Blood Press Res), the glutamate transporter EEAT1 (Boehmer et al., (2003) Cardiovasc Res), the cardiac voltage-gated Na+ channel SCN5A (Boehmer et al., (2003) J Neurochem), ENaC (Friedrich et al., (2003) Pflügers Arch), Na+-dicarboxylate cotransporter 1 (Böhmer et al., (2004) Biochem Biophys Res Commun), the chloride channel ClCa/barttin (Embark et al., (2004) Pflügers Arch), the epithelial Ca2+ channel TRPV5 (Embark et al., (2004) Pflügers Arch), the Na+-phosphate cotransporter NaPi2b (Palmada M. et al., (2004) Cell Physiol Biochem), the amino acid transporter ASCT2 (Palmada M. et al., (2005) Cell Physiol Biochem), GluR1, and GluR6 (Strutz-Seebohm et al., (2005); Strutz-Seebohm et al., (2005a) J Physiol). For the same reasons mentioned above for SGK2, additional studies on SGK3 will be necessary to evaluate the physiological relevance of these findings.
1.4. Tissue distribution of SGK isoforms SGK isoforms are expressed in numerous tissues and cell lines. Among the three kinases, SGK1 (Waldegger et al., (1997) Proc Natl Acad Sci USA; Kobayashi et al., (1999) Biochem J) and SGK3 show the broadest distribution, with expression in many tissues including the brain, placenta, lung, liver, pancreas, kidney, heart and skeletal muscle. In situ hybridization studies localized SGK1 mRNA in several epithelial and/or nonepithelial cells within the brain (Wärntges et al., (2002) Cell Physiol Biochem; Nishida et al., (2004) Brain Res; Tsai et al., (2002) Proc Natl Acad Sci USA; Stichel et al., (2005) Eur J Neurosci; Gonzalez-Nicolini A. and McGinty F., (2002) Brain Res Gene ExpPatterns), eye (Rauz et al., (2003) Exp Eye Res; Rauz et al., (2003a) Invest Ophtalmol Vis Sci), lung (Wärntges et al., (2002) Cell Physiol Biochem) liver (Fillon et al., (2002) Comp Biochem Physiol A Mol Integr Physiol), ovary (Alliston et al., (2000) Endocrinology), pancreas (Klingel et al., (2000) Am J Physiol Gastrointest Liver Physiol), intestine (Waldegger et al., (1999) Gastroentherology) and kidney (Chen et al., (1999) Proc Natl Acad Sci USA; Friedrich et al., (2002) Kidney Blood Press res; Huber et al., (2001) Pflügers Archive). SGK1 mRNA expression is established very early in embryonic development, as indicated by in situ hybridizations on whole-mount preparations of mouse embryo (Lee et al., (2001) Mech Dev). By embryonic day (E) 8.5, SGK1 is already highly expressed in the decidua and yolk sac. By days E9.5– E12.5 it is found in the developing heart, eye, and lung, and it becomes highly expressed by days E13.5–E16.5 in the brain choroid plexus, kidney distal tubules, bronchi/bronchiole, adrenal glands, liver, thymus, and intestine (Lee et al., (2001) Mech Dev). In contrast to SGK1 and SGK3, SGK2 reveals a more restricted distribution and is highly abundant only in the liver, kidney, and pancreas, where it is found in two different SGK2 species, referred to as SGK2α and SGK2β (Kobayashi et al., (1999) Biochem J). SGK isoform expression varies also between cell lines cultured in vitro. Similar to its expression pattern in vivo, SGK1 is broadly expressed in cultured cells and is readily detectable in, for example, hepatoma cells, fibroblasts and mammary tumor cells (Webster et al., (1993) J Biol Chem; Kobayashi et al., (1999) Biochem J). By contrast, SGK2 mRNA is expressed in hepatoma cells but not in fibroblasts, whereas SGK3 is found in fibroblasts but not in hepatoma cells. Remarkably, all three SGK isoforms are expressed in cells derived from the renal cortical collecting duct (Naray-Fejes-Toth et al., (2004) Proc Natl Acad Sci USA). |
[p. 12]
Like SGK2, SGK3 has been implicated in the regulation of numerous transporters and channels, including K+ channels (Gamper et al., 2002; Henke et al., 2004; Embark et al., 2003), Na+,K+-ATPase (Henke et al., 2002), the glutamate transporter EEAT1 (Boehmer et al., 2003), the cardiac voltage-gated Na+ channel SCN5A (Boehmer et al., 2003), ENaC (Friedrich et al., 2003), Na+-dicarboxylate cotransporter 1 (Boehmer et al., 2004), the chloride channel ClCa/barttin (Embark et al., 2004), the epithelial Ca2+ channel TRPV5 (Embark et al., 2004), the Na+-phosphate cotransporter NaPi1b (Palmada et al., 2004), the amino acid transporter ASCT2 (Palmada et al., 2005), GluR1, and GluR6 (Strutz-Seebohm et al., 2005; Strutz-Seebohm et al., 2005a). For the same reasons mentioned above for SGK2, additional studies on SGK3 will be necessary to evaluate the physiological relevance of these findings. [...] [p. 14] 1.4 Tissue Distribution of SGK Isoforms SGK isoforms are expressed in numerous tissues and cell lines. Among the three kinases, SGK1 (Webster et al., 1993; Waldegger et al., 1997; Kobayashi et al., 1999) and Sgk3 (Kobayashi et al., 1999) show the broadest distribution, with expression in many tissues including the brain, placenta, lung, liver, pancreas, kidney, heart and skeletal muscle. In situ hybridization studies localized SGK1 mRNA in several epithelial and/or nonepithelial cells within the brain (Warntges et al., 2002; Nishida et al., 2004; Tsai et al., 2002; Stichel et al., 2005; Gonzalez-Nicolini and McGinty 2003), eye (Rauz et al., 2003; Rauz et al., 2003a), lung (Waerntges et al., 2002), liver (Fillon et al., 2002), ovary (Alliston et al., 2000), pancreas (Klingel et al., 2000), intestine (Waldegger et al., 1999), and kidney (Chen et al., 1999; Friedrich et al., 2002; Huber et al., 2001). SGK1 mRNA expression is established very early in embryonic development, as indicated by in situ hybridizations on whole-mount preparations of mouse embryo (Lee et al., 2001). By embryonic day (E) 8.5, SGK1 is already highly expressed in the decidua and yolk sac. By days E9.5– E12.5 it is found in the developing heart, eye, and lung, and it becomes highly expressed by days E13.5–E16.5 in the brain choroid plexus, kidney distal tubules, bronchi/brochioli, adrenal glands, liver, thymus, and intestine (Lee et al., 2001). In contrast to SGK1 and SGK3, SGK2 reveals a more restricted distribution and is highly abundant only in the liver, kidney, and pancreas, where it is found in two different SGK2 species, referred to as SGK2α and [p. 15] SGK2β (Kobayashi et al., 1999). SGK isoform expression varies also between cell lines cultured in vitro. Similar to its expression pattern in vivo, SGK1 is broadly expressed in cultured cells and is readily detectable in, for example, hepatoma cells, fibroblasts, and mammary tumor cells (Webster et al., 1993; Kobayashi et al., 1999). By contrast, SGK2 mRNA is expressed in hepatoma cells but not in fibroblasts, whereas SGK3 is found in fibroblasts but not in hepatoma cells. Remarkably, all three SGK isoforms are expressed in cells derived from the renal cortical collecting duct (Naray-Fejes-Toth et al., 2004). |
The source is not given. |
|