Genome-Wide CRISPR-Cas9 Screen Identifies SMCHD1 as a Restriction Factor for Herpesviruses.

Intrinsic immunity is the frontline of host defense against invading pathogens. To combat viral infection, mammalian hosts deploy cell-intrinsic effectors to block viral replication prior to the onset of innate and adaptive immunity. In this study, SMCHD1 is identified as a pivotal cellular factor that restricts Kaposi's sarcoma-associated herpesvirus (KSHV) lytic reactivation through a genome-wide CRISPR-Cas9 knockout screen. Genome-wide chromatin profiling revealed that SMCHD1 associates with the KSHV genome, most prominently the origin of lytic DNA replication (ORI-Lyt). SMCHD1 mutants defective in DNA binding could not bind ORI-Lyt and failed to restrict KSHV lytic replication. Moreover, SMCHD1 functioned as a pan-herpesvirus restriction factor that potently suppressed a wide range of herpesviruses, including alpha, beta, and gamma subfamilies. SMCHD1 deficiency facilitated the replication of a murine herpesvirus in vivo. These findings uncovered SMCHD1 as a restriction factor against herpesviruses, and this could be harnessed for the development of antiviral therapies to limit viral infection. IMPORTANCE Intrinsic immunity represents the frontline of host defense against invading pathogens. However, our understanding of cell-intrinsic antiviral effectors remains limited. In this study, we identified SMCHD1 as a cell-intrinsic restriction factor that controlled KSHV lytic reactivation. Moreover, SMCHD1 restricted the replication of a wide range of herpesviruses by targeting the origins of viral DNA replication (ORIs), and SMCHD1 deficiency facilitated the replication of a murine herpesvirus in vivo. This study helps us to better understand intrinsic antiviral immunity, which may be harnessed to develop new therapeutics for the treatment of herpesvirus infection and the related diseases.

Electrodeposited Polyaniline Nanofibers and MoO3 Nanobelts for High-Performance Asymmetric Supercapacitor with Redox Active Electrolyte.

Transition molybdenum oxides (MoO3) and conductive polymer (polyaniline, PANI) nanomaterials were fabricated and asymmetric supercapacitor (ASC) was assembled with MoO3 nanobelts as negative electrode and PANI nanofibers as a positive electrode. Branched PANI nanofibers with a diameter of 100 nm were electrodeposited on Ti mesh substrate and MoO3 nanobelts with width of 30-700 nm were obtained by the hydrothermal reaction method in an autoclave. Redox active electrolyte containing 0.1 M Fe2+/3+ redox couple was adopted in order to enhance the electrochemical performance of the electrode nano-materials. As a result, the PANI electrode shows a great capacitance of 3330 F g-1 at 1 A g-1 in 0.1 M Fe2+/3+/0.5 M H2SO4 electrolyte. The as-assembled ASC achieved a great energy density of 54 Wh kg-1 at power density of 900 W kg-1. In addition, it displayed significant cycle stability and its capacitance even increased to 109% of the original value after 1000 charge-discharge cycles. The superior performance of the capacitors indicates their promising application as energy storage devices.

Graphene/Carbon Paper Combined with Redox Active Electrolyte for Supercapacitors with High Performance.

Graphene/carbon paper is prepared by pyrolyzing graphene modified cellulose filter paper and directly used as a binder-free electrode to assemble a supercapacitor (SC) with a redox active electrolyte, containing a Fe3+/Fe2+ additive. By the graphene incorporation and the carbonization of the cellulose fibers, both the microstructure and the electrical conductivity of the carbon paper are promoted greatly. The filter paper derived carbon (FPC) electrode exhibits a specific capacitance (Cs) of 2832 F·g-1 in a 1 M H2SO4 + 0.5 M Fe3+/Fe2+ electrolyte at 1 A·g-1, which is about 81 times that in a normal H2SO4 electrolyte. With the modification of graphene, the capacitive performance of the SC is enhanced further and a remarkable Cs of 3396 F·g-1 at 1 A·g-1 is achieved for a graphene modified filter paper carbon (GFPC) electrode, which remains at ~632 F·g-1 at 10 A·g-1. The free standing GFPC electrode also exhibits good cycling stability (93.8% of capacitance retention after 2000 cycles) and an energy density of 118 Wh·kg-1 at a power density of 500.35 W·kg-1, all of which are much higher than those of FPC. These encouraging results suggest that the graphene modification of electrode materials combined with a Fe3+/Fe2+ redox active electrolyte is a prospective measure to fabricate SC with an ultrahigh performance.

Redox-Active Gel Electrolyte Combined with Branched Polyaniline Nanofibers Doped with Ferrous Ions for Ultra-High-Performance Flexible Supercapacitors.

In this work, the effects of utilizing an Fe2+/Fe3+ redox-active electrolyte and Fe2+-doped polyaniline (PANI) electrode material on the performance of an assembled supercapacitor (SC) were studied. The concentration of the redox couple additive in the electrolyte of the SC was optimized to be 0.5 M. With the optimized concentration of 0.4 M Fe2+, the doped PANI branched nanofibers electropolymerized onto titanium mesh were much thinner, cleaner, and more branched than normal PANI. A specific capacitance (Cs) of 8468 F g-1 for the 0.4 M Fe2+/PANI electrode in the 1 M H2SO4 + 0.5 M Fe2+/Fe3+ gel electrolyte and an energy density of 218.1 Wh kg-1 at a power density of 1854.4 W kg-1 for the resultant SC were achieved, which were much higher than those of the conventional PANI electrode tested in a normal H2SO4 electrolyte (404 F g-1 and 24.9 Wh kg-1). These results are among the highest reported for PANI-based SCs in the literature so far and demonstrate the potential effectiveness of this strategy to improve the electrochemical performance of flexible SCs by modifying both the electrode and electrolyte.