10.6084/m9.figshare.12141153.v1
Michalina Kazek
Michalina
Kazek
The importance of trehalose metabolism for proper Drosophila immune response during parasitoid infection
TAGC 2020
2020
Drosophila
Immunometabolism
trehalose
carbohydrate metabolism
Immunology
Invertebrate Biology
Cell Metabolism
2020-04-20 23:37:56
Poster
https://tagc2020.figshare.com/articles/poster/The_importance_of_trehalose_metabolism_for_proper_Drosophila_immune_response_during_parasitoid_infection/12141153
<p>The primary circulating sugar in insects is trehalose,
which is usually present in hemolymph in much higher concentration than
glucose. Trehalose is a non-reducing sugar, which can be rapidly cleaved to two
glucose molecules by the trehalase enzyme. In Drosophila, there are two
versions of trehalase, cytoplasmic and secreted. The secreted version is used
to maintain circulating glucose, by hydrolyzing trehalose, at a stable level
and appears to be part of systemic regulation of carbohydrate metabolism. However,
this systemic regulation cannot distinguish the supply of different organs. The
activated immune system becomes privileged in the acquisition of nutrients, and
this raises extremely interesting question of whether activated insect immune
cells (hemocytes) favor direct uptake of trehalose and conversion to glucose by
cytoplasmic trehalase, thereby being independent of systemic regulation.
Therefore, we test the role of trehalose and its metabolism during the immune
response. Experiments with 13C-labeled trehalose show that hemocytes during
parasitoid infection increase the uptake of trehalose, which is partially
metabolized by glycolysis but mainly by the pentose phosphate pathway. In
addition, transcript-specific expression analysis, immune cell-specific RNAi
and mitotic recombination have shown us the importance of cytoplasmic trehalase
for immune cells. The absence of the trehalase enzyme, specifically in
hemocytes, significantly reduces resistance to parasitoid. These results are in
agreement with the privileged access of immune cells to nutrients during
infection, which is required for efficient resistance, and demonstrate an
alternative evolutionary strategy for such a privileged access in insects.</p>