Epidermal growth factor stimulates phosphorylation of eukaryotic initiation factor 4B, independently of protein kinase C

Wolthuis, Rob M. F.; Cremers, A.F.M.; Kasperaitis, Marcelle A.M.; Mast, C. van der; Voorma, Harry O.; Boonstra, Johannes

doi:10.1016/0167-4889(93)90035-n

Cited by 7 publications

(2 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We studied two transformed cell lines, the ts-src-transformed MDCK cells and epidermoid carcinoma cell line A431 (Behrens et al, 1993;Wolthuis et al, 1993) to see their response to the PMA treatment. The src-transformed MDCK cells have a very poor actin cytoskeleton and fodrin is diffusely distributed in the cytoplasm (Sormunen et al, 1999).…”

Section: Discussionmentioning

confidence: 99%

Translocation of MARCKS and reorganization of the cytoskeleton by PMA correlates with the ion selectivity, the confluence, and transformation state of kidney epithelial cell lines

et al. 1999

View full text Add to dashboard Cite

The role of protein kinase C (PKC) in the regulation of the cytoskeleton of epithelial cells with tightly sealed contacts, poor contacts, and without contacts were investigated by incubating them with a protein kinase C activator phorbol myristoyl acetate (PMA). The morphology and organization of the membrane skeleton and stress fibers as well as the localization of an actin-bundling PKC substrate MARCKS in confluent MDCK cells originating from the distal tubulus of dog kidney, LLC-PK1 cells originating from the proximal tubulus of pig kidney, src-transformed MDCK cells, epidermoid carcinoma A431 cells, and MDCK cells grown in low calcium medium (LC medium) in low density were visualized with phase contrast and immunofluorescence microscopy. Four different responses to the PMA-treatment in actin-based structures of cultured epithelial cells were observed: 1) disintegration of the membrane skeleton in confluent MDCK cells; 2) depolymerization of the stress fibers in confluent MDCK and LLC-PK1 cells; 3) formation of the membrane skeleton in A431 cells, and 4) formation of the stress fibers and membrane skeleton in LC-MDCK cells. Thus, it seems that in fully confluent tightly sealed epithelium, activation of PKC has a deleterious effect on actin-based structures, whereas in cells without contacts or loose contacts, activation of PKC by PMA results in improvement of actin-based cytoskeletal structures. The main difference between the two kidney cell lines used is their selectivity to ion transport: the monolayer of LLC-PK1 cells is anion selective and MDCK cells cation selective. We propose a model where alterations in the ionic milieu within the MDCK cells by means of cation channels affect the disintegration of the membrane skeleton. The distribution of MARCKS followed the distribution of fodrin in both cell lines upon PMA-treatment, suggesting that phosphorylation of MARCKS by PKC may contribute in the regulation of the integrity of the membrane skeleton.

show abstract

Section: Discussionmentioning

confidence: 99%

Translocation of MARCKS and reorganization of the cytoskeleton by PMA correlates with the ion selectivity, the confluence, and transformation state of kidney epithelial cell lines

et al. 1999

View full text Add to dashboard Cite

show abstract

“…This effect is accomplished by suppression of Ras-stimulated transformation via c-jun NH2-terminal kinase (JNK) signal transduction pathway (Kennedy et al, 2003), or Raf-1-independent deregulation of p38 MAPK cascade (Pruitt et al, 2002). Activation of eiF2B and phosphorylation of 4E-BPs as well as eiF-4G by insulin treatment (Proud and Denton, 1997;von Manteuffel et al, 1997;Kleijn et al, 1998), phosphorylation of eiF-4B and eiF-4G via EGFmediated stimulation of S6 Kinase (Wolthuis et al, 1993;Kleijn et al, 1998), and phosphorylation of 4E-BP1 and increase in protein synthesis (Wang and Proud, 2002) are mechanisms of Ras-mediated translational control in oncogenesis.…”

Section: Ras/raf/erk Pathwaymentioning

confidence: 99%

Postgenomic global analysis of translational control induced by oncogenic signaling

Rajasekhar

Holland

2004

Oncogene

View full text Add to dashboard Cite

Phosphorylation of elF‐4E and initiation of protein synthesis in P19 embryonal carcinoma cells

Kleijn

Voorma

Thomas

1995

J of Cellular Biochemistry

Self Cite

View full text Add to dashboard Cite

Mitogenic stimulation of protein synthesis is accompanied by an increase in eIF-4E phosphorylation. The effect on protein synthesis by induction of differentiation is less well known. We treated P19 embryonal carcinoma cells with the differentiating agent retinoic acid and found that protein synthesis increased during the first hour of addition. However, the phosphorylation state, as well as the turnover of phosphate on eIF-4E, remained unchanged. Apparently, the change in protein synthesis after RA addition is regulated by another mechanism than eIF-4E phosphorylation. By using P19 cells overexpressing the EGF receptor, we show that the signal transduction pathway that leads to phosphorylation of eIF-4E is present in P19 cells; the EGF-induced change in phosphorylation of eIF-4E in these cells is likely to be regulated by a change in eIF-4E phosphatase activity. These results suggest that the onset of retinoic acid-induced differentiation is triggered by a signal transduction pathway which involves changes in protein synthesis, but not eIF-4E phosphorylation.

show abstract

Epidermal growth factor stimulates phosphorylation of eukaryotic initiation factor 4B, independently of protein kinase C

Cited by 7 publications

References 46 publications

Translocation of MARCKS and reorganization of the cytoskeleton by PMA correlates with the ion selectivity, the confluence, and transformation state of kidney epithelial cell lines

Translocation of MARCKS and reorganization of the cytoskeleton by PMA correlates with the ion selectivity, the confluence, and transformation state of kidney epithelial cell lines

Postgenomic global analysis of translational control induced by oncogenic signaling

Phosphorylation of elF‐4E and initiation of protein synthesis in P19 embryonal carcinoma cells

Contact Info

Product

Resources

About