Phorbol ester binding and protein kinase C activity in normal and transformed human keratinocytes

Journal Article · Tue Sep 01 04:00:00 EDT 1987 · Experimental Cell Research; (USA)

DOI:https://doi.org/10.1016/0014-4827(87)90101-7· OSTI ID:6621990

Snoek, G T; de Laat, S W ^[1]; Boonstra, J ^[2]; Ponec, M ^[3]

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1. Netherlands Institute of Developmental Biology, Utrecht (Netherlands)
2. Univ. of Utrecht (Netherlands)
3. University Hospital, Leiden (Netherlands)

Normal keratinocytes, SV40-transformed keratinocytes (SVK{sub 14}), and various squamous carcinoma cell (SCC) lines have been used as an in vitro model system to study the properties of phorbol ester receptor and protein kinase C expression during keratinocyte differentiation. The cell lines used exhibit a decreasing capacity to differentiate; moreover, all cell lines respond to a low external Ca{sup 2+} concentration by a decreased capacity to differentiate. Normal keratinocytes exhibited the highest number of phorbol ester receptors as compared to the other cell lines, while each individual cell line exhibited a higher number of phorbol ester receptors during growth under normal Ca{sup 2+} conditions as compared to cells grown under low Ca{sup 2+} conditions. The apparent dissociation constant (K{sub d}) demonstrated only small variations in the various cell lines. These studies revealed differences between protein kinase C properties from the two cell lines grown under normal and low Ca{sup 2+} conditions. The differences included the effect of phorbol 12-myristate 13-acetate (PMA) on the redistribution pattern of protein kinase C between the cytoplasmic and particulate fractions as well as the activating effect of diolein in vitro on protein kinase C activity. These observations demonstrate that the functional protein kinase C activity of keratinocytes is determined by various endogenous and exogenous activators and that these activators are modulated differently in various cell lines, under various growth conditions (low Ca{sup 2+} versus normal Ca{sup 2+}).

• OSTI ID: 6621990
• Journal Information: Experimental Cell Research; (USA), Journal Name: Experimental Cell Research; (USA) Vol. 172:1; ISSN ECREA; ISSN 0014-4827
• Country of Publication: United States
• Language: English

Related Subjects

550301* -- Cytology-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ANIMAL CELLS
ANIMAL TISSUES
ANIMALS
BIOLOGICAL EFFECTS
BODY
CARCINOGENS
CARCINOMAS
CELL DIFFERENTIATION
CELL PROLIFERATION
CELL TRANSFORMATIONS
CORTICOSTEROIDS
DISEASES
ENZYME ACTIVITY
ENZYMES
EPITHELIUM
ESTERS
GLUCOCORTICOIDS
GROWTH FACTORS
HYDROCORTISONE
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
KETONES
MAMMALS
MAN
MITOGENS
NEOPLASMS
ONCOGENIC TRANSFORMATIONS
ORGANIC COMPOUNDS
ORGANS
PHORBOL ESTERS
PHOSPHORUS-GROUP TRANSFERASES
PHOSPHOTRANSFERASES
PREGNANES
PRIMATES
PROTEINS
RADIORECEPTOR ASSAY
SKIN
STEROIDS
TISSUES
TRACER TECHNIQUES
TRANSFERASES
TUMOR CELLS
VERTEBRATES