Signal transduction through extracellular signal-regulated kinase-like pp57 blocked in differentiated cells having low protein kinase Cβ activity Journal Article


Authors: Lee, H.; Ghose-Dastidar, J.; Winawer, S.; Friedman, E.
Article Title: Signal transduction through extracellular signal-regulated kinase-like pp57 blocked in differentiated cells having low protein kinase Cβ activity
Abstract: pp57 is a cytoplasmic kinase which is related antigenically and functionally to the extracellular signal regulated kinase or the mitogen- activated kinase family of signal transduction proteins. Two undifferentiated colon carcinoma cell lines responded to the diacylglycerol diolein by growth and a rapid 3-4-fold increase in tyrosine phosphorylation of pp57, and smaller increases in threonine and serine phosphorylation. By enhancing tyrosine phosphorylation of pp57, diolein increased pp57 kinase activity on myelin basic protein. Two enterocytic differentiated colon carcinoma cell lines, when treated with diolein, exhibited neither increased pp57 tyrosine phosphorylation nor increased growth. Both enterocytic lines exhibited 30% of the total PKC activity, 10-20% of the abundance of PKCβ as detected by Western blotting with anti-peptide antisera, and 10-20% of the PKCβ activity, by immune complex kinase reactions, that was expressed in the undifferentiated cell lines. The abundance of three other PKC isozymes, α, ε, and ζ appeared unchanged in the undifferentiated and enterocytic lines, reflecting their common parental cell line origin. The association between loss of PKCβ activity and blocked signaling through pp57 in each of two cell lines suggests that PKCβ is part of a signal transduction system activating pp57.
Keywords: signal transduction; human cell; cancer growth; cell division; protein kinases; mitogenesis; cell differentiation; cancer cell culture; enzyme activation; tumor cells, cultured; enzyme activity; tyrosine; phosphorylation; enzyme regulation; protein kinase c; colon carcinoma; isoenzymes; diglycerides; isoenzyme; ca(2+)-calmodulin dependent protein kinase; oncogene proteins v-rel; human; priority journal; article; support, u.s. gov't, p.h.s.; retroviridae proteins, oncogenic; glycerol dioleate
Journal Title: Journal of Biological Chemistry
Volume: 268
Issue: 7
ISSN: 0021-9258
Publisher: American Society for Biochemistry and Molecular Biology  
Date Published: 1993-03-05
Start Page: 5255
End Page: 5263
Language: English
PUBMED: 8383133
PROVIDER: scopus
DOI/URL:
Notes: Article -- Export Date: 1 March 2019 -- Source: Scopus
Citation Impact
MSK Authors
  1. Sidney J Winawer
    274 Winawer