Matches in SemOpenAlex for { <https://semopenalex.org/work/W2058743622> ?p ?o ?g. }
- W2058743622 endingPage "292" @default.
- W2058743622 startingPage "277" @default.
- W2058743622 abstract "Previous studies showed that lens epithelial cells proliferate rapidly in the embryo and that a lens mitogen, most likely derived from the blood, is present in the anterior chamber of the embryonic eye (Hyatt, G. A., and Beebe, D. C.,Development117, 701–709, 1993). Messenger RNAs for several growth factor receptors have been identified in embryonic lens epithelial cells. We tested several growth factors that are ligands for these receptors for their ability to maintain lens cell proliferation. Embryo serum, PDGF, GM-CSF, and G-CSF maintained lens cell proliferation, but NGF, VEGF, and HGF did not. This and a previous study (Potts, J. D., Harocopos, G. J., and Beebe, D. C.,Curr. Eye Res.12, 759–763, 1993) detected members of the Janus kinase family (Jaks) in the developing lens. Because Jaks are central players in the Jak-STAT-signaling pathway, we identified STAT proteins in the lens and tested whether they were phosphorylated in response to mitogens. STAT1 and STAT3, but not STAT 5 were detected in chicken embryo lens epithelial cells. Only STAT3 was found in terminally differentiated lens fiber cells. STAT1 and STAT3 were phosphorylated in lens cells analyzed immediately after removal from the embryo and when lens epithelial explants were treated with embryo serum, PDGF, or GM-CSF, but not with NGF. Chicken embryo vitreous humor or IGF-1, factors that stimulate lens cell differentiation, but not proliferation, did not cause STAT phosphorylation. When lens epithelial cells were cultured for 4 h in unsupplemented medium, STAT1 and STAT3 declined to nearly undetectable levels. Treatment with PDGF or embryo serum for an additional 15 min restored STAT1 and -3 levels. This recovery was blocked by cycloheximide, but not actinomycin D, suggesting that STAT levels are regulated at the level of translation. STAT levels were maintained in epithelial explants by lens mitogens, but not by factors that stimulated lens fiber differentiation. Both factors that stimulated lens cell proliferation and those that caused fiber differentiation protected cultured lens epithelial cells from apoptosis. These data suggest that the factor(s) responsible for lens cell proliferationin vivoactivates the Jak–STAT-signaling pathway. They also indicate that growth factors maintain STAT protein levels in lens epithelial cells by promoting the translation of STAT mRNA, an aspect of STAT regulation that has not been described previously. Signaling by most of the growth factors and cytokines known to activate the Jak-STAT pathway has been disrupted in mice by mutation or targeted deletion. Consideration of the phenotypes of these mice suggests that the factor responsible for lens cell proliferationin vivomay be a growth factor or cytokine that has not yet been described." @default.
- W2058743622 created "2016-06-24" @default.
- W2058743622 creator A5061607843 @default.
- W2058743622 creator A5069375705 @default.
- W2058743622 creator A5072637747 @default.
- W2058743622 date "1998-12-01" @default.
- W2058743622 modified "2023-10-17" @default.
- W2058743622 title "Activation of the Jak–STAT-Signaling Pathway in Embryonic Lens Cells" @default.
- W2058743622 cites W1547704219 @default.
- W2058743622 cites W1553277501 @default.
- W2058743622 cites W1605768520 @default.
- W2058743622 cites W1649526546 @default.
- W2058743622 cites W1702674772 @default.
- W2058743622 cites W1857978595 @default.
- W2058743622 cites W1932371007 @default.
- W2058743622 cites W193519295 @default.
- W2058743622 cites W1948282121 @default.
- W2058743622 cites W1959486232 @default.
- W2058743622 cites W1967909285 @default.
- W2058743622 cites W1969979508 @default.
- W2058743622 cites W1972044265 @default.
- W2058743622 cites W1975304753 @default.
- W2058743622 cites W1975687767 @default.
- W2058743622 cites W1977341142 @default.
- W2058743622 cites W1977801207 @default.
- W2058743622 cites W1978983255 @default.
- W2058743622 cites W1981799488 @default.
- W2058743622 cites W1982589114 @default.
- W2058743622 cites W1985233226 @default.
- W2058743622 cites W1989361398 @default.
- W2058743622 cites W1989730434 @default.
- W2058743622 cites W1996493396 @default.
- W2058743622 cites W1997887425 @default.
- W2058743622 cites W2001643449 @default.
- W2058743622 cites W2002273560 @default.
- W2058743622 cites W2003505321 @default.
- W2058743622 cites W2005638713 @default.
- W2058743622 cites W2006540383 @default.
- W2058743622 cites W2008647600 @default.
- W2058743622 cites W2011549360 @default.
- W2058743622 cites W2011642803 @default.
- W2058743622 cites W2012219330 @default.
- W2058743622 cites W2012438019 @default.
- W2058743622 cites W2013036001 @default.
- W2058743622 cites W2014409793 @default.
- W2058743622 cites W2017040356 @default.
- W2058743622 cites W2017684091 @default.
- W2058743622 cites W2022527563 @default.
- W2058743622 cites W2024418426 @default.
- W2058743622 cites W2035134361 @default.
- W2058743622 cites W2035184168 @default.
- W2058743622 cites W2036571449 @default.
- W2058743622 cites W2037868864 @default.
- W2058743622 cites W2037945038 @default.
- W2058743622 cites W2041267913 @default.
- W2058743622 cites W2042339641 @default.
- W2058743622 cites W2049651574 @default.
- W2058743622 cites W2052120035 @default.
- W2058743622 cites W2054838803 @default.
- W2058743622 cites W2056153206 @default.
- W2058743622 cites W2058472264 @default.
- W2058743622 cites W2059817089 @default.
- W2058743622 cites W2060271381 @default.
- W2058743622 cites W2063034492 @default.
- W2058743622 cites W2063627258 @default.
- W2058743622 cites W2065321603 @default.
- W2058743622 cites W2067376187 @default.
- W2058743622 cites W2070242833 @default.
- W2058743622 cites W2072536348 @default.
- W2058743622 cites W2074729230 @default.
- W2058743622 cites W2076600290 @default.
- W2058743622 cites W2077549378 @default.
- W2058743622 cites W2079673523 @default.
- W2058743622 cites W2082760987 @default.
- W2058743622 cites W2083398588 @default.
- W2058743622 cites W2083802827 @default.
- W2058743622 cites W2088027708 @default.
- W2058743622 cites W2089582261 @default.
- W2058743622 cites W2091898207 @default.
- W2058743622 cites W2093392246 @default.
- W2058743622 cites W2094431180 @default.
- W2058743622 cites W2095720878 @default.
- W2058743622 cites W2101283727 @default.
- W2058743622 cites W2108317548 @default.
- W2058743622 cites W2110153861 @default.
- W2058743622 cites W2115333784 @default.
- W2058743622 cites W2122506044 @default.
- W2058743622 cites W2127412428 @default.
- W2058743622 cites W2134962084 @default.
- W2058743622 cites W2137333423 @default.
- W2058743622 cites W2143508222 @default.
- W2058743622 cites W2144944614 @default.
- W2058743622 cites W2147028876 @default.
- W2058743622 cites W2151427219 @default.
- W2058743622 cites W2153236138 @default.
- W2058743622 cites W2153469946 @default.
- W2058743622 cites W2153829422 @default.
- W2058743622 cites W2155493652 @default.