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Title: Contrasting role of phospholipase C-{gamma}1 in the expression of immediate early genes induced by epidermal or platelet-derived growth factors

Abstract

While significant progress has been achieved in identifying the signal transduction elements that operate downstream of activated receptor tyrosine kinases, it remains unclear how different receptors utilize these signaling elements to achieve a common response. This study compares the capacity of epidermal growth factor (EGF) and platelet-derived growth factor (PDGF) to elicit the induction of immediate early gene (IEG) mRNAs in the presence or absence of phospholipase C-{gamma}1 (PLC-{gamma}1). The results show that while PDGF induction of nearly all IEG mRNAs is abrogated in plcg1 null cells, EGF induction of the same genes is variable in the null cells and exhibits three distinct responses. Five IEG mRNAs (Nup475, Cyr61, TF, Gly, TS7) are completely inducible by EGF in the presence or absence of PLC-{gamma}1, while three others (JE, KC, FIC) exhibit a stringent requirement for the presence of PLC-{gamma}1. The third type of response is exhibited by c-fos and COX-2. While these mRNAs are completely induced by EGF in the absence of PLC-{gamma}1, the time course of their accumulation is significantly delayed. No IEG was identified as completely inducible by EGF and PDGF in the absence of PLC-{gamma}1. Electrophoretic mobility shift assays (EMSA) demonstrate that PLC-{gamma}1 is necessary for nuclearmore » extracts from PDGF-treated cells, but not EGF-treated cells, to interact with probes for AP-1 or NF-{kappa}B.« less

Authors:
 [1];  [1];  [2]
  1. Department of Biochemistry, Vanderbilt University School of Medicine, 606 Light Hall, Nashville, TN 37232-0146 (United States)
  2. Department of Biochemistry, Vanderbilt University School of Medicine, 606 Light Hall, Nashville, TN 37232-0146 (United States). E-mail: graham.carpenter@vanderbilt.edu
Publication Date:
OSTI Identifier:
20775348
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Cell Research; Journal Volume: 312; Journal Issue: 6; Other Information: DOI: 10.1016/j.yexcr.2005.11.034; PII: S0014-4827(05)00566-5; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; CHEMILUMINESCENCE; GENES; GROWTH FACTORS; PHOSPHOTRANSFERASES; RECEPTORS; TYROSINE

Citation Formats

Liao Hongjun, Santos, Josue de los, and Carpenter, Graham. Contrasting role of phospholipase C-{gamma}1 in the expression of immediate early genes induced by epidermal or platelet-derived growth factors. United States: N. p., 2006. Web. doi:10.1016/j.yexcr.2005.11.034.
Liao Hongjun, Santos, Josue de los, & Carpenter, Graham. Contrasting role of phospholipase C-{gamma}1 in the expression of immediate early genes induced by epidermal or platelet-derived growth factors. United States. doi:10.1016/j.yexcr.2005.11.034.
Liao Hongjun, Santos, Josue de los, and Carpenter, Graham. 2006. "Contrasting role of phospholipase C-{gamma}1 in the expression of immediate early genes induced by epidermal or platelet-derived growth factors". United States. doi:10.1016/j.yexcr.2005.11.034.
@article{osti_20775348,
title = {Contrasting role of phospholipase C-{gamma}1 in the expression of immediate early genes induced by epidermal or platelet-derived growth factors},
author = {Liao Hongjun and Santos, Josue de los and Carpenter, Graham},
abstractNote = {While significant progress has been achieved in identifying the signal transduction elements that operate downstream of activated receptor tyrosine kinases, it remains unclear how different receptors utilize these signaling elements to achieve a common response. This study compares the capacity of epidermal growth factor (EGF) and platelet-derived growth factor (PDGF) to elicit the induction of immediate early gene (IEG) mRNAs in the presence or absence of phospholipase C-{gamma}1 (PLC-{gamma}1). The results show that while PDGF induction of nearly all IEG mRNAs is abrogated in plcg1 null cells, EGF induction of the same genes is variable in the null cells and exhibits three distinct responses. Five IEG mRNAs (Nup475, Cyr61, TF, Gly, TS7) are completely inducible by EGF in the presence or absence of PLC-{gamma}1, while three others (JE, KC, FIC) exhibit a stringent requirement for the presence of PLC-{gamma}1. The third type of response is exhibited by c-fos and COX-2. While these mRNAs are completely induced by EGF in the absence of PLC-{gamma}1, the time course of their accumulation is significantly delayed. No IEG was identified as completely inducible by EGF and PDGF in the absence of PLC-{gamma}1. Electrophoretic mobility shift assays (EMSA) demonstrate that PLC-{gamma}1 is necessary for nuclear extracts from PDGF-treated cells, but not EGF-treated cells, to interact with probes for AP-1 or NF-{kappa}B.},
doi = {10.1016/j.yexcr.2005.11.034},
journal = {Experimental Cell Research},
number = 6,
volume = 312,
place = {United States},
year = 2006,
month = 4
}
  • A cohort of the serum and growth factor regulated immediate-early gene set is induced with slower kinetics than c-fos. Two of the first immediate-early genes characterized as such, c-myc and JE, are contained within this subset. cis-acting genomic elements mediating induction of the slower responding subset of immediate-early genes have never been characterized. Herein the authors characterize two widely separated genomic elements which are together essential for induction of the murine JE gene by platelet-derived growth factor, serum, interleukin-1, and double-stranded RNA. One of these elements is novel in several regards. It is a 7-mer, TTTTGTA, found in the proximalmore » 3[prime] sequences downstream of the JE stop codon. The 3[prime] element is position dependent and orientation independent. It does not function in polyadenylation, splicing, or destabilization of the JE transcript. Copies of the 7-mer or its inverse are found at comparable 3[prime] sites in 25 immediate-early genes that encode transcription factors or cytokines. Given its general occurrence, the 7-mer may be a required cis-acting control element mediating induction of the immediate-early gene set. 64 refs., 10 figs., 1 tab.« less
  • Addition of platelet-derived growth factor (PDGF), recombinant insulin-like growth factor I (rIGF-I) or epidermal growth factor (EGF) to BALB/c 3T3 fibroblasts causes a marked increase in the binding of (/sup 125/I) diferric transferrin to cell surface receptors. This effect is very rapid and is complete within 5 minutes. The effect is transient with (/sup 125/I) diferric transferrin binding returning to control values within 25 minutes. In contrast, PDGF and rIGF-I cause a prolonged stimulation of (/sup 125/I) diferric transferrin binding that could be observed up to 2 hours. The increase in the binding of (/sup 125/I) diferric transferrin caused bymore » growth factors was investigated by analysis of the binding isotherm. EGF, PDGF and rIGF-I were found to increase the cell surface expression of transferrin receptors rather than to alter the affinity of the transferrin receptors. Furthermore, PDGF and rIGF-I stimulated the sustained uptake of (/sup 59/Fe) diferric transferrin by BALB/c 3T3 fibroblasts. Thus, the effect of these growth factors to increase the cell surface expression of the transferrin receptor appears to have an important physiological consequence.« less
  • Cultured arterial smooth muscle cells (SMC) can produce platelet-derived growth factor (PDGF)-like molecules. This property raises the possibility that SMC-derived PDGFs function as autocrine/paracrine regulators in the formation and maintenance of the artery wall. In this study the authors have asked if levels of mRNAs directing synthesis of PDFG are modulated in aortic SMC during postnatal development. The authors report here that genes encoding PDGF A- and B-chain precursors are expressed at similar low levels in intact aortas from newborn and adult rats. Marked differences in regulation of transcript abundance of these genes were revealed when aortic SMC were grownmore » in cell culture. PDGF B-chain transcripts accumulated in passaged newborn rat SMC but not adult rat SMC, whereas PDGF A-chain RNA was found in comparable amounts in SMC from both age groups. Similarly, SMC from newborn rats secreted at least 60-fold more PDGF-like activity into conditioned medium than did adult rat SMC. These results show that PDGF A- and B-chain genes are transcribed in the normal rat aorta and provide evidence for age-related change in the control of PDGF B-chain gene expression in aortic SMC. Independent regulation of transcript levels in cultured SMC leaves open the possibility that PDGFs of different composition (AA, AB, BB) play different roles in normal function of the artery wall.« less
  • MHC class II molecules expressed in lymphoid and nonlymphoid cells act as signal-transducer molecules. We demonstrate that engagement of MHC class II molecules on human IFN-{gamma}-treated fibroblast-like synoviocytes by their natural ligand, the staphylococcal enterotoxin A (SEA), selectively induces the production of interstitial collagenase over the expression of the tissue inhibitor of metalloproteinase (TIMP). Collagenase gene expression required de novo protein synthesis and was accompanied by high levels of PGE{sub 2} production, suggesting its implication in this response. Two inhibitors that affect prostaglandin biosynthesis, indomethacin and arachidonyl-trifluoromethyl-ketone, inhibited both PGE{sub 2} production and collagenase gene expression. The addition of exogenousmore » PGE{sub 2} to inhibitor-treated cells partially restored the SEA-induced collagenase, indicating a role for PGE{sub 2} in this response. As cyclooxygenases (COX-1 and -2), cytosolic phospholipase A{sub 2} (cPLA{sub 2}), and secreted PLA{sub 2} (sPLA{sub 2}) are the enzymes potentially implicated in prostaglandin synthesis, their involvement in SEA-induced collagenase was investigated. The mRNA levels of COX-2 and cPLA{sub 2} rapidly increased following ligation of MHC class II molecules, while COX-1 and sPLA{sub 2} mRNA levels were unchanged and transiently depressed, respectively. SEA-induced COX-2 mRNA was translated adequately to protein, whereas cPLA{sub 2} protein level was not enhanced, but rapidly phosphorylated, a process previously linked to the enzyme activation. In conclusion, this work demonstrates a selective induction of collagenase gene expression over its natural inhibitor TIMP in human IFN-{gamma}-treated fibroblast-like synoviocytes mediated, at least in part, by PGE{sub 2}, and provides evidence that signaling via MHC class II molecules induces the production of PGE{sub 2} through enhanced production of COX-2 and possibly activation of the cPLA{sub 2}. 46 refs., 10 figs.« less
  • Treatment of mouse NIH 3T3 cells with the phorbol ester tumor promoter, phorbol 12-myristate 13-acetate, results in altered transcription of several genes as measured in nuclear run-off experiments. The first set of genes, whose altered transcription occurs rapidly in the absence of protein synthesis, is typified by induction of c-myc and c-fos and decreased transcription of ..cap alpha../sup 2/ type I procollagen. This work demonstrates the existence of a second class of genes whose rapidly increased transcription requires prior protein synthesis, which is represented by the gene encoding a secreted lysosomal protein, MEP. Similar induction of MEP RNA is seenmore » after treatment with platelet-derived growth factor or transformation with Kirsten sarcoma virus.« less