Congresos y reuniones científicas
Título:
ROLE OF ACID HYDROLASES DURING FOLLICULAR ATRESIA IN A VECTOR OF CHAGAS´ DISEASE.
Autor/es:
LEYRIA J; AGUIRRE SA; FRUTTERO LL; 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, unfavourable nutritional conditions induce biochemical
and cellular changes in the ovarian tissue such as the early degradation
of vitellin (Vt), the main oocyte protein, and the atresia of
some follicles. In some species, the changes accomplished during
atresia are elicited to promote the recycling of proteins to sustain
younger follicles. In this study, we have explored biochemical
changes that take place during the process of follicular atresia induced
by a nutritional deficit in the hematophagous Dipetalogaster
maxima, a vector of Chagas’ disease. We have emphasized in the
roles of two acid hidrolases, cathepsin D (CD) and acid phosphatase
(AP). The study included assays of western-blot, the measurement
of enzyme activities, immunofluoresce as well as in vitro assays of
Vt proteolysis employing specific inhibitors of CD and AP. Results
showed that proteolysis of Vt occurred gradually during the transition
from vitellogenesis to follicular atresia. Higher activities of
AP and CD were registered at early and late atresia, in comparison
to pre-vitellogenesis and vitelogenesis. In vitro assays showed that
AP is important in promoting Vt degradation, which in turn was
mediated by CD. Altogether, the biochemical changes exhibited
during follicular atresia in D. maxima could reflect the ability of
the ovarian tissue to face a new vitellogenic cycle if nutritional
conditions improve. The results also provide a better understanding
of the biology of reproduction of Chagas’ disease vectors.