INVESTIGADORES
SALVADOR Gabriela Alejandra
artículos
Título:
Involvement of lysophosphatidic acid, sphingosine 1-phosphate and ceramide 1-phosphate in the metabolization of phosphatidic acid by lipid phosphate phosphatases in bovine rod outer segments
Autor/es:
PASQUARE SUSANA; SALVADOR GABRIELA; GIUSTO NORMA
Revista:
NEUROCHEMICAL RESEARCH
Editorial:
Springer
Referencias:
Lugar: USA; Año: 2008 vol. 33 p. 1205 - 1215
ISSN:
0364-3190
Resumen:
Involvement of Lysophosphatidic Acid, Sphingosine 1-Phosphate
and Ceramide 1-Phosphate in the Metabolization of Phosphatidic
Acid by Lipid Phosphate Phosphatases in Bovine Rod Outer
Segments
Abstract The aim of the present research was to evaluate
the generation of [2-3H]diacylglycerol ([2-3H]DAG) from
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
the generation of [2-3H]diacylglycerol ([2-3H]DAG) from
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
the generation of [2-3H]diacylglycerol ([2-3H]DAG) from
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
The aim of the present research was to evaluate
the generation of [2-3H]diacylglycerol ([2-3H]DAG) from
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
3H]diacylglycerol ([2-3H]DAG) from
[2-3H]-Phosphatidic acid ([2-3H]PA) by lipid phosphate
phosphatases (LPPs) at different concentrations of lysophosphatidic
acid (LPA), sphingosine 1-phosphate (S1P),
and ceramide 1-phosphate (C1P) in purified ROS obtained
from dark-adapted retinas (DROS) or light-adapted retinas
(BLROS) as well as in ROS membrane preparations
depleted of soluble and peripheral proteins. Western blot
analysis revealed the presence of LPP3 exclusively in all
membrane preparations. Immunoblots of entire ROS and
depleted ROS did not show darklight differences in LPP3
levels. LPPs activities were diminished by 53% in BLROS
with respect to DROS. The major competitive effect on PA
hydrolysis was exerted by LPA and S1P in DROS and by
C1P in BLROS. LPPs activities in depleted ROS were
similar to the activity observed in entire DROS and
BLROS, respectively. LPA, S1P and C1P competed at
different extent in depleted DROS and BLROS. Sphingosine
and ceramide inhibited LPPs activities in entire and
depleted DROS. Ceramide also inhibited LPPs activities in
entire and in depleted BLROS. Our findings are indicative
of a different degree of competition between PA and LPA,
S1P and C1P by LPPs depending on the illumination state
of the retina.
phosphatases (LPPs) at different concentrations of lysophosphati