INIBIOLP   05426
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE LA PLATA "PROF. DR. RODOLFO R. BRENNER"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Functional analysis of fatty acid binding proteins expressed in enterocyte
Autor/es:
RODRIGUEZ SAWICKI LUCIANA; FALOMIR LOCKHART LISANDRO JORGE; BOTTASSO NATALIA; FRANCHINI GISELA; STORCH JUDITH; CÓRSICO BETINA
Lugar:
Buenos Aires
Reunión:
Conferencia; International Gregorio Weber Conference; 2011
Resumen:
Long
chain fatty acids (LCFA) are needed as a source of metabolic energy, membrane
biogenesis, second messengers, modulation of gene expression; and are associated
with cell growth, differentiation, apoptosis and inflammatory processes. Lipid
hydrolysis in the intestinal lumen releases great quantities of LCFA. Once
inside the enterocyte, LCFA can be reversibly bound to two homologous proteins:
Intestinal and Liver Fatty Acid Binding Proteins (I- and LFABP) (1,2,3).
Classical functions proposed include cytosolic buffers and transporters of
hydrophobic ligands, but new studies position them as key components for
regulatory systems. The present work was conducted to evaluate FABP´s specific
roles in the lipid metabolism and inflammatory response of the enterocyte. For
this purpose, we obtained a cellular model of Caco-2 cells with ablated
expression of LFABP and analyzed the assimilation and metabolism of LCFA.
Knock-down clones showed marked variations in LCFA assimilation rates and
differences in oleate distribution among complex lipid species. Cell
proliferation and differentiation were also slowed in the clones. In addition,
the effect of LCFA in the induction of an inflammatory response in Caco-2 cells
was studied, showing increased levels of cytokines mRNA after LCFA exposure.
These results indicate that LFABP plays a specific role in the enterocyte lipid
metabolism. We plan to expand this line of research including the análisis of
FABP-protein interactions with candidate proteins using Fluorescene Resonance
Transfer Energy (FRET). Although some interacting partners have been reported
for several members of this family (4, 5, 6), no one is yet known for IFABP.
Proteins participating in lipid assimilation, its metabolism and transcription
factors are strong candidates to interact with FABPs. At the moment, LFABP,
IFABP and candidate proteins cDNAs are being ligated to different visible
fluorescent proteins. Pairs of proteins will be transfected in Caco-2 cells and
analyzed using confocal microscopy for FRET signal. The information obtained
combining lipid metabolism, immunological processes and protein-protein
interactions will contribute to asses intestinal FABPs specific functions and
their importance in the enterocyte cell biology.