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A typical characteristics of polydnavirus (PDV) infection is a persistent immunosuppression, governed by the viral integration and expression of virulence genes. Recently, activation of caspase-3 by Microplitis bicoloratus bracovirus (MbBV) to cleave Innexins, gap junction proteins, has been highlighted, further promoting apoptotic cell disassembly and apoptotic body (AB) formation. However, whether ABs play a role in immune suppression remains to be determined. Herein, we show that ABs transmitted immunosuppressive signaling, causing recipient cells to undergo apoptosis and dismigration. Furthermore, the insertion of viral–host integrated motif sites damaged the host genome, stimulating eIF5A nucleocytoplasmic transport and activating the eIF5A-hypusination translation pathway. This pathway specifically translates apoptosis-related host proteins, such as P53, CypA, CypD, and CypJ, to drive cellular apoptosis owing to broken dsDNA. Furthermore, translated viral proteins, such Vank86, 92, and 101, known to complex with transcription factor Dip3, positively regulated DHYS and DOHH transcription maintaining the activation of the eIF5A-hypusination. Mechanistically, MbBV-mediated extracellular vesicles contained inserted viral fragments that re-integrated into recipients, potentially via the homologous recombinant repair system. Meanwhile, this stimulation regulated activated caspase-3 levels via PI3K/AKT 308 and 473 dephosphorylation to promote apoptosis of granulocyte-like recipients Sf9 cell; maintaining PI3K/AKT 473 phosphorylation and 308 dephosphorylation inhibited caspase-3 activation leading to dismigration of plasmatocyte-like recipient High Five cells. Together, our results suggest that integration-mediated eIF5A hypusination drives extracellular vesicles for continuous immunosuppression.

A novel iridium complex with sterically bulky camphor-derives group as β-diketonate,i.e.,(2-phenylpyridinato-N,C2′) irdium(Ⅲ)(3-acetyl-camphor) [Ir(ppy)2(acam)],was synthesized and it was characterized by 1H NMR,ESI-MS,and elementary analysis.This complex exhibited a higher phototoluminescence quantum efficiency(0.54) than(2-phenylpyridinato-N,C2′) irdium(Ⅲ)(acetylacetonate) [Ir(ppy)2(acac)](0.34) in 2-methyl-tetrahydrofuran solution.Efficient green phosphorescent polymer light-emitting diodes using Ir(ppy)2(acam) as dopants showed high efficiencies and stable EL spectra,with maximum current efficiency of 15.1 cd/A,maximum power efficiency of 4.23 lm/W and maximum brightness of 9 939 cd/m2 at doping mass fraction of 1%.

An undoped electrophosphorescent organic light-emitting diode is fabricated using a pure platinum(II) (2-phenylpyridinato-N, C2) (3-benzoyl-camphor) [(ppy)pt(bcam)] phosphorescent layer acting as the emitting layer. A maximum power efficiency ηp of 6.62 lm/W and current efficiency of 14.78 cd/A at 745cd/m2 are obtained from the device. The roll-off percentage of ηp of the pure phosphorescent phosphor layer device is reduced to 5% at a current density of 20 mA/cm2, which is about 11% for conventional phosphorescent devices. The low roll-off efficiency is attributed to the phosphorescent material, which has the molecular structure of a strong steric hindrance effect.

Geometry optimization of target complexes were performed at the level of B3LYP/ LanL2DZ/6-31G*, and their absorption spectra and the second nonlinear optical properties were calculated at the TD-B3LYP/LANL2DZ/6-31++G** level and B3LYP/LANL2DZ/6-31++G** level, respectively. The results indicate that the introduction of conjugated substituting groups of electron-donor and conjugated substituting groups of strong electron-accepter makes maximal absorption wavelength red-shifted and blue-shifted, respectively. The introduction of conjugated substituting groups resultes in obvious increase of second nonlinear optical properties for IrQ3 complexes. The electronic transfer belongs to intra-ligand charge transfer （LLCT） for AgQ complexes, and LLCT mixed with partially metal-to-ligand charge transfer for PtQ2 and IrQ3 complexes. There is no effect of substituting groups on transition properties for AgQ, PtQ2 and IrQ3 complexes.