scholarly journals Tyrosine Residues in the Granulocyte Colony-stimulating Factor (G-CSF) Receptor Mediate G-CSF-induced Differentiation of Murine Myeloid Leukemic (M1) Cells

1996 ◽  
Vol 271 (43) ◽  
pp. 26947-26953 ◽  
Author(s):  
Sandra E. Nicholson ◽  
Robyn Starr ◽  
Ulrike Novak ◽  
Douglas J. Hilton ◽  
Judith E. Layton
Blood ◽  
1996 ◽  
Vol 87 (6) ◽  
pp. 2148-2153 ◽  
Author(s):  
RM Barge ◽  
JP de Koning ◽  
K Pouwels ◽  
F Dong ◽  
B Lowenberg ◽  
...  

Granulocyte colony-stimulating factor (G-CSF) induces rapid phosphorylation of JAK kinases as well as activation of the p21ras route through interaction with its specific receptor (G-CSF-R). The cytoplasmic membrane-proximal region of G-CSF-R (amino acids 631 to 684) is necessary for proliferation induction and activation of JAK2. In contrast, activation of Shc and Syp, signaling molecules implicated in the p21ras signaling route, depends on the phosphorylation of tyrosine residues located in the membrane-distal region (amino acids 685 to 813) of G-CSF-R. We investigated whether G-CSF-induced activation of signaling complexes of the p21ras route depends on the function of the membrane-proximal cytoplasmic region of G-CSF-R. A G- CSF-R mutant was constructed in which tryptophan 650 was replaced by arginine and expressed in BAF3 cells (BAF/W650R). In contrast to BAF3 cell transfectants expressing wild-type G-CSF-R, BAF/W650-R cells did not proliferate and did not show activation of JAK2, STAT1, or STAT3 in response to G-CSF. Immunoprecipitations with anti-Shc and anti-Grb2 antisera showed that mutant W650R also failed to activate Syp and Shc. These data indicate that the membrane-proximal cytoplasmic domain of G- CSF-R is not only crucial for proliferative signaling and activation of JAK2 and STATs, but is also required for activation of the p21ras route, which occurs via the membrane-distal region of G-CSF-R.


2021 ◽  
pp. 096032712110085
Author(s):  
EA Ahmed ◽  
AM Abd-Eldayem ◽  
E Ahmed

Acetaminophen (APAP) is often used as an antipyretic and analgesic agent. Overdose hepatotoxicity, which often results in liver cell failure and liver transplantation, is a severe complication of APAP usage. To save the liver and save lives from acute liver damage caused by APAP, the search for new strategies for liver defense is important. Wistar rats have been used for the induction of APAP hepatotoxicity. Elevated levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) were evaluated for liver toxicity. In addition, the levels of hepatic tissue oxidative markers such as malondialdehyde (MDA), nitric oxide (NO) increased while glutathione (GSH) was depleted and catalase (CAT) activity was curtailed. The biochemical findings were consistent with the changes in histology that suggested liver damage and inflammation. Treated rats with N-acetylcysteine (N-AC) and granulocyte colony stimulating factor (G-CSF) showed a decrease in serum levels of ALT, AST and LDH, while the level of ALP in the G-CSF group was still high. After administration of APAP, treatment with N-AC or G-CSF substantially reduced the level of MDA and NO while maintaining the GSH content and CAT activity. Treatment with N-AC and G-CSF after administration of APAP has also attenuated inflammation and hepatocytes necrosis. The results of this study showed that G-CSF could be viewed as an alternative hepatoprotective agent against APAP-induced acute liver injury compared to N-AC.


2008 ◽  
Vol 22 (7) ◽  
pp. 635-639 ◽  
Author(s):  
Miyako Morooka ◽  
Kazuo Kubota ◽  
Yuji Murata ◽  
Hitoshi Shibuya ◽  
Kimiteru Ito ◽  
...  

1988 ◽  
Vol 256 (1) ◽  
pp. 213-218 ◽  
Author(s):  
P Wingfield ◽  
R Benedict ◽  
G Turcatti ◽  
B Allet ◽  
J J Mermod ◽  
...  

Human granulocyte colony-stimulating factor (G-CSF), and a mutant having a Ser for Cys substitution at residue 18 were produced in Escherichia coli strain W3110. About 60 mg of pure protein was obtained from 50 g of wet cells with a recovery of about 20%. The proteins were characterized physically and chemically, including determination of disulphide bonds, which were found to exist between residues 37-43 and 65-75. Cys-18 is not involved in disulphide bond formation and was substituted by Ser with no effects on gross protein conformation or biological activity. Both the wild-type and the mutant recombinant-derived proteins, although not glycosylated, possess colony-stimulating activities. In a bioassay using the murine myelomonocytic leukaemic cell line WEH1 3B D+, activities were obtained which were similar to those of natural G-CSF and of a glycosylated recombinant-derived human G-CSF produced in monkey cells.


Sign in / Sign up

Export Citation Format

Share Document