CIBICI   14215
CENTRO DE INVESTIGACION EN BIOQUIMICA CLINICA E INMUNOLOGIA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
THE PHYSIOLOGICAL RELEVANCE OF MIDGUT MEMBRANE PROTEINS IN THE PROCESS OF LIPID TRANSFER IN A VECTOR OF CHAGAS DISEASE
Autor/es:
FRUTTERO LL; STARIOLO R; CARLINI CR; RUBIOLO ER; CANAVOSO LE
Lugar:
San Juan, Argentina
Reunión:
Jornada; 2º Reunión Conjunta de Sociedades de Biología de la República Argentina, XVIII Jornadas Científicas de la Sociedad de Biología de Córdoba; 2011
Institución organizadora:
Sociedades de Biología de la República Argentina
Resumen:
In insects, lipid transport through hemolymph is accomplished by
lipophorin, the main high-density lipoprotein. It is suggested that
lipophorin transfers its lipid cargo to tissues by a process mediated
by uncharacterized non-endocytic receptors. In this context, we have
analyzed the lipid transfer between circulating lipophorin and the
midgut tissue in Panstrongylus megistus, a Chagas disease vector.
We made special focus in the characterization of membrane proteins
that interacted with lipophorin. Immunofluorescence and in
vivo assays with fluorescently labeled lipophorin showed that this
lipoprotein interacted mainly with the sub-epithelial layer of the
midgut. No intracellular signal compatible with endocytosis was
observed. The use of lipophorin-Bodipy-FA (a fatty acid analog)
demonstrated that lipid transfer at the midgut was bidirectional,
and showed no dependence with the nutritional status of the insect.
By combining ligand blotting, immunoprecipitation, and mass spectrometry
approaches, several midgut membrane proteins interacting
with lipophorin were identified, including the β subunit of the
ATP synthase complex (β-ATPase), which was pointed out in human
cell lines as a lipoprotein receptor. These findings are in agreement
with the function of lipophorin as a reusable shuttle and suggest
for the first time a novel role for β-ATPase as a non-endocytic
lipophorin receptor in the midgut of P. megistus.