INIBIOLP   05426
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE LA PLATA "PROF. DR. RODOLFO R. BRENNER"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Endonuclear lipids have a high proportion of neutral lipids
Autor/es:
LAYERENZA, JUAN PABLO; TRICERRI, ALEJANDRA M.; GARCÍA DE BRAVO, MARGARITA M.; POLO, MÓNICA; VES-LOSADA, ANA
Lugar:
Carlos Paz, Córdoba
Reunión:
Congreso; XLIV Reunión anual de SAIB; 2008
Institución organizadora:
SAIB
Resumen:
Nuclear lipids are mostly found in the double nuclear membrane, and
in a minor proportion they are associated to chromatin and to the
nuclear matrix (Mx). Composition and physico-chemical properties of
these lipid pools are very important as they are the sources of
nuclear signal transduction system of PI, PC and SM as well FA
involved in genetic regulation. The aim of this work was to analyze
nuclear neutral lipids composition (NL), their location and nuclear
fluidity (GP: Generalized polarization). Thus, whole nuclei and
nuclear double membranedepleted nuclei (Mx) were isolated from
rat liver cells. Purity of nuclear fractions was determined by electronic
microscopy and marker proteins. Nuclei lipids mainly contain 84%
and 16% of PL an NL, respectively, as follows:
PC>PE>TAG>PI>Cho>SM/PS>>CE. Endonuclear lipids (Mx) are
mainly constituted of 57% PL and 43% NL, as follows:
TAG³PC>PE³Cho>SM/PI/PS/CE. Thus, the mayor lipid pool in nuclei
is PC, while TAG and PC are mainly found inside nuclei. Mx were
analized by Laurdan GP (espectrofluorometric and 2 Foton
microscopy), presenting less fluidity than nuclei.
In conclusion, endonuclear lipids are enriched in NL (TAG, Cho, CE).
Despite the minor amount of PL, these are enriched in SM and PS.
TAG and PC were found to be the major lipids inside the nuclei, and
they may be alternative sources of FA with different properties and
regulation.