(A) Infection by female Leptopilina spp. parasitic
wasps introduces not only wasp eggs into the body cavities and hemolymph of
fruit fly larvae, but also venom gland products which includes spiked, 300-nm
VLPs. VLP bioactivity is known to be necessary for the infective success of
L. heterotoma, rather than other venom constituents
[6, 9]. (B) Intact anterior lymph
gland lobes from uninfected control Dome-MESO-GFP fly larvae.
GFP marks the stem-like progenitors in the medulla. (C)
Dome-MESO-GFP glands of Lb 17-infected larvae
show lamellocyte differentiation (white arrowhead) and lobe dispersal (white
arrow). (D) Progenitors are depleted in
Dome-MESO-GFP anterior lobes infected with
Lh 14. (B – D) White asterisks mark
dorsal vessels. (E) Scanning EMs of Lb 17 and
(F)
Lh 14 VLPs. (G) CryoEM of Lh 14
VLPs: The external lipid bilayer is contiguous, extending from spike bases
(black arrows) at the VLP core to spike tips (white arrowhead). The black
arrowhead marks area in zoom, bottom right.