Fig 1.
Expression level interactions between BmDredd and other two apoptosis-related genes in MSG and PSG during metamorphosis.
(A) Expression levels in MSG and in PSG. L5D3-L5D7: day 3 to day 7 of the fifth larval instar. W: wandering stage. sp12h: 12 h of spinning. PD1: 1-day-old pupa. PD2: 2-day-old pupa. (B) The increase of BmDredd expression induced by ecdysone in MSG and PSG, P<0.5. Early, middle and late means the time of feeding ecdysone at L5D3, L5D5 to L5D6 and L5D7 to wandering respectively.
Fig 2.
Role of BmDredd in SG apoptosis.
(A) BmDredd expression levels in different silkworm tissues at sp18h, P<0.05. (B) BmDredd expression levels in SG after injecting Z-DEVD-fmk for about 36 h, P<0.05.
Fig 3.
TEM of the SG during the middle of the spinning stage.
(a), (a1) and (a2): cavity of SG (CSG). (b), (b1) and (b2):nucleus of SG. (c to c2) and (d to d2): cytoplasm. Yellow arrows in b, b1 and b2: condensed chromatin, yellow frames in b1 and b2: dispersed chromatin. Red arrows in c, c1, and d to d2: mitochondrion, red frames in d and d2: endoplasmic reticulum (ER), red circles in c2: golgi apparatus. AB: apoptosis body. A: Control SG injecting with dsRNA-EGFP at L5D7. B: dsRNA injected during the middle of the fifth instar (about middle of L5D6). C: dsRNA injected during late stage of the fifth instar (about early wandering). D: BmDredd expression levels in SG at 30 h post-BmDredd interference. E: Caspase3-like activities in PSG after dsRNA treatments for about 30 h, P<0.5.
Fig 4.
Overexpression of BmDredd in silkworm.
(A) Fluorescence microscopy, a1 and a2: green fluorescence indicative of successful transfection and overexpression of the PXL-BAC-U6-Dredd-GFP. a3 and a4: DAPI and Rhodamine staining, DAPI (blue fluorescence): nuclei, Rhodamine (red fluorescence): BmDredd. a1, a3: control, a2, a4: overexpression of BmDredd. (B) BmDredd expression levels in the SG after 48h overexpression. P<0.01. (C) caspase3-like activity of SG after 48 h overexpression.