TY - JOUR
T1 - A system to select for mutant LLC-PK1 cells affected in camp mediated hormonal response using a photoactivatable analogue of vasopressin
AU - Luzius, Heike
AU - Jans, David A.
AU - Fahrenholz, Falk
PY - 1990/1/1
Y1 - 1990/1/1
N2 - The photoreactive analogue of vasopressin, [1-(3-mercapto) propionic acid, 8-(N6-4-azidophenyl-amidino)lysine] vasopressin (apa-LVP) could be used to elicit stimulation of cAMP production in LLC-PK renal epithelial cells, detectable up to 24 h after photoacti-vation by flash photolysis. This is in contrast to cells treated with vasopressin, or apa-LVP without photoactivation, where cAMP synthesis is down regulated within 4 h. The prolonged stimulation of cAMP production induced by photoactivation of apa-LVP was demonstrated to be cytotoxic to LLC-PK1 cells, whereas the vasopressin receptor negative LLC-PK1 mutant M18 was resistant to the cytotoxic effect. A selection strategy was developed for mutants resistant to this long-term stimulation of cAMP production, whereby multiple cycles of treatment with apa-LVP and photoactivation were used. Mutants so selected were then characterized using a novel screening system for detection of the production of urokinase-type plasminogen activator in response to cAMP agonists. One mutant was examined and found to be impaired in hormonal responsiveness, whereby hormone and forskolin stimulated cAMP-mediated responses were markedly reduced. It exhibited resistance to the long-term stimulation of cAMP production elicited by apa-LVP and photoactivation. This implies that apa-LVP can be used to select for novel mutants specifically impaired in cAMP metabolism and in particular down-regulation of cAMP response.
AB - The photoreactive analogue of vasopressin, [1-(3-mercapto) propionic acid, 8-(N6-4-azidophenyl-amidino)lysine] vasopressin (apa-LVP) could be used to elicit stimulation of cAMP production in LLC-PK renal epithelial cells, detectable up to 24 h after photoacti-vation by flash photolysis. This is in contrast to cells treated with vasopressin, or apa-LVP without photoactivation, where cAMP synthesis is down regulated within 4 h. The prolonged stimulation of cAMP production induced by photoactivation of apa-LVP was demonstrated to be cytotoxic to LLC-PK1 cells, whereas the vasopressin receptor negative LLC-PK1 mutant M18 was resistant to the cytotoxic effect. A selection strategy was developed for mutants resistant to this long-term stimulation of cAMP production, whereby multiple cycles of treatment with apa-LVP and photoactivation were used. Mutants so selected were then characterized using a novel screening system for detection of the production of urokinase-type plasminogen activator in response to cAMP agonists. One mutant was examined and found to be impaired in hormonal responsiveness, whereby hormone and forskolin stimulated cAMP-mediated responses were markedly reduced. It exhibited resistance to the long-term stimulation of cAMP production elicited by apa-LVP and photoactivation. This implies that apa-LVP can be used to select for novel mutants specifically impaired in cAMP metabolism and in particular down-regulation of cAMP response.
UR - http://www.scopus.com/inward/record.url?scp=0024997711&partnerID=8YFLogxK
U2 - 10.3109/10799899009064658
DO - 10.3109/10799899009064658
M3 - Article
C2 - 2175811
AN - SCOPUS:0024997711
SN - 1079-9893
VL - 10
SP - 61
EP - 80
JO - Journal of Receptors and Signal Transduction
JF - Journal of Receptors and Signal Transduction
IS - 1-2
ER -