Premium
Alkyllysophospholipid ET‐18‐OCH 3 acts as an activator of protein kinase C in HL‐60 cells
Author(s) -
Heesbeen Ellen C.,
Verdonck Leo F.,
Hermans Stefanie W.G.,
van Heugten Hans G.,
Staal Gerard E.J.,
Rijksen Gert
Publication year - 1991
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(91)81267-c
Subject(s) - protein kinase c , protein kinase a , prkcq , kinase , biochemistry , chemistry , mitogen activated protein kinase kinase , cytotoxic t cell , microbiology and biotechnology , activator (genetics) , phorbol , in vitro , map2k7 , biology , cyclin dependent kinase 2 , receptor
HL‐60 cells are very sensitive to the cytotoxic action of ether lipids. Several hypotheses have been proposed to explain this cytotoxicity. We investigated the influence of the alkylphospholipid ET‐18‐OCH 3 on the activity of protein kinase C. HL‐60 cells were incubated with ET‐18‐OCH 3 at a concentration of 20 μg/ml for 4 h. After the incubation the membrane fraction of the HL‐60 cells was isolated and the activity of protein kinase C was determined while it was still associated with the membrane, using the synthetic peptide substrate [Ser 25 ]‐protein kinase C (19–31) as a protein kinase C specific substrate. The activity of the membrane‐bound protein kinase C was increased in HL‐60 cells treated with ET‐18‐OCH 3 compared to untreated HL‐60 cells. The increase in protein kinase C activity was not a consequence of translocation and appeared to be additive to the effect of the phorbol ester 12‐myristate 13‐acetate. In contrast, solubilized protein kinase C from HL‐60 cells could be inhibited or stimulated in vitro by ET‐18‐OCH 3 , dependent on the mode of addition of ET‐18‐OCH 3 and phospholipids.