HIV-1 Vpr drives epigenetic remodeling to enhance virus transcription and latency reactivation.

Despite decades of research, the primary proviral function of the HIV-1 Vpr accessory protein remains enigmatic. Vpr is essential for pathogenesis and for virus replication in myeloid cells, but the underlying cause-and-effect mechanism(s) driving these phenomena are poorly understood. Canonically, Vpr hijacks a cellular ubiquitin ligase complex to target several dozen host proteins for proteasomal degradation.

Layer-number-dependent photoswitchability in 2D MoS-diarylethene hybrids.

Molybdenum disulfide (MoS) is a notable two-dimensional (2D) transition metal dichalcogenide (TMD) with properties ideal for nanoelectronic and optoelectronic applications. With growing interest in the material, it is critical to understand its layer-number-dependent properties and develop strategies for controlling them. Here, we demonstrate a photo-modulation of MoS flakes and elucidate layer-number-dependent charge transfer behaviors.

PARP1-TRIM44-MRN loop dictates the response to PARP inhibitors.

PARP inhibitors (PARPi) show selective efficacy in tumors with homologous recombination repair (HRR)-defects but the activation mechanism of HRR pathway in PARPi-treated cells remains enigmatic. To unveil it, we searched for the mediator bridging PARP1 to ATM pathways by screening 211 human ubiquitin-related proteins. We discovered TRIM44 as a crucial mediator that recruits the MRN complex to damaged chromatin, independent of PARP1 activity.

DSS1 restrains BRCA2's engagement with dsDNA for homologous recombination, replication fork protection, and R-loop homeostasis.

DSS1, essential for BRCA2-RAD51 dependent homologous recombination (HR), associates with the helical domain (HD) and OB fold 1 (OB1) of the BRCA2 DSS1/DNA-binding domain (DBD) which is frequently targeted by cancer-associated pathogenic variants. Herein, we reveal robust ss/dsDNA binding abilities in HD-OB1 subdomains and find that DSS1 shuts down HD-OB1's DNA binding to enable ssDNA targeting of the BRCA2-RAD51 complex. We show that C-terminal helix mutations of DSS1, including the cancer-associated R57Q mutation, disrupt this DSS1 regulation and permit dsDNA binding of HD-OB1/BRCA2-DBD.

Photoswitchable optoelectronic properties of 2D MoSe/diarylethene hybrid structures.

The ability to modulate optical and electrical properties of two-dimensional (2D) semiconductors has sparked considerable interest in transition metal dichalcogenides (TMDs). Herein, we introduce a facile strategy for modulating optoelectronic properties of monolayer MoSe with external light. Photochromic diarylethene (DAE) molecules formed a 2-nm-thick uniform layer on MoSe, switching between its closed- and open-form isomers under UV and visible irradiation, respectively.

Akt enhances the vulnerability of cancer cells to VCP/p97 inhibition-mediated paraptosis.

Valosin-containing protein (VCP)/p97, an AAA+ ATPase critical for maintaining proteostasis, emerges as a promising target for cancer therapy. This study reveals that targeting VCP selectively eliminates breast cancer cells while sparing non-transformed cells by inducing paraptosis, a non-apoptotic cell death mechanism characterized by endoplasmic reticulum and mitochondria dilation. Intriguingly, oncogenic HRas sensitizes non-transformed cells to VCP inhibition-mediated paraptosis.

Crucial roles of the BRCA1-BARD1 E3 ubiquitin ligase activity in homology-directed DNA repair.

The tumor-suppressor breast cancer 1 (BRCA1) in complex with BRCA1-associated really interesting new gene (RING) domain 1 (BARD1) is a RING-type ubiquitin E3 ligase that modifies nucleosomal histone and other substrates. The importance of BRCA1-BARD1 E3 activity in tumor suppression remains highly controversial, mainly stemming from studying mutant ligase-deficient BRCA1-BARD1 species that we show here still retain significant ligase activity. Using full-length BRCA1-BARD1, we establish robust BRCA1-BARD1-mediated ubiquitylation with specificity, uncover multiple modes of activity modulation, and construct a truly ligase-null variant and a variant specifically impaired in targeting nucleosomal histones.

Morphology Engineering of Hybrid Supercapacitor Electrodes from Hierarchical Stem-like Carbon Networks with Flower-like MoS Structures.

There is a critical need to develop high-performance supercapacitors that can complement and even rival batteries for energy storage. This work introduces a strategy to drastically enhance the energy storage performance of a supercapacitor by engineering electrode morphologies with ternary composites offering distinct benefits for the energy storage application. The electrodes were fabricated with conductive networks of carbon nanotubes (CNTs) coated with a zeolitic imidazole framework (ZIF) for high ion diffusivity and ion-accumulating molybdenum disulfide (MoS) with various morphologies.

Transcriptional regulation and chromatin dynamics at DNA double-strand breaks.

In eukaryotic cells, DNA damage can occur at any time and at any chromatin locus, including loci at which active transcription is taking place. DNA double-strand breaks affect chromatin integrity and elicit a DNA damage response to facilitate repair of the DNA lesion. Actively transcribed genes near DNA lesions are transiently suppressed by crosstalk between DNA damage response factors and polycomb repressive complexes.

Synthesis of a nitrogen doped reduced graphene oxide based ceramic polymer composite nanofiber film for wearable device applications.

In this study, piezoelectric composite nanofiber films were fabricated by introducing nitrogen-doped-reduced-graphene-oxide as a conductive material to a P(VDF-TrFE) polymer and a BiScO-PbTiO ceramic composite employing an electrospinning process. Nitrogen was doped/substituted into rGO to remove or compensate defects formed during the reduction process. Electro-spinning process was employed to extract piezoelectric composite nanofiber films under self-poling condition.

Recent progress in 2D hybrid heterostructures from transition metal dichalcogenides and organic layers: properties and applications in energy and optoelectronics fields.

Atomically thin transition metal dichalcogenides (TMDs) present extraordinary optoelectronic, electrochemical, and mechanical properties that have not been accessible in bulk semiconducting materials. Recently, a new research field, 2D hybrid heteromaterials, has emerged upon integrating TMDs with molecular systems, including organic molecules, polymers, metal-organic frameworks, and carbonaceous materials, that can tailor the TMD properties and exploit synergetic effects. TMD-based hybrid heterostructures can meet the demands of future optoelectronics, including supporting flexible, transparent, and ultrathin devices, and energy-based applications, offering high energy and power densities with long cycle lives.

The chromatin remodeler RSF1 coordinates epigenetic marks for transcriptional repression and DSB repair.

DNA lesions impact on local transcription and the damage-induced transcriptional repression facilitates efficient DNA repair. However, how chromatin dynamics cooperates with these two events remained largely unknown. We here show that histone H2A acetylation at K118 is enriched in transcriptionally active regions.

USP39 promotes non-homologous end-joining repair by poly(ADP-ribose)-induced liquid demixing.

Mutual crosstalk among poly(ADP-ribose) (PAR), activated PAR polymerase 1 (PARP1) metabolites, and DNA repair machinery has emerged as a key regulatory mechanism of the DNA damage response (DDR). However, there is no conclusive evidence of how PAR precisely controls DDR. Herein, six deubiquitinating enzymes (DUBs) associated with PAR-coupled DDR were identified, and the role of USP39, an inactive DUB involved in spliceosome assembly, was characterized.

Improvement of Figure of Merit Pb(Zr,Ti)O₃-Pb(Zn,Ni,Nb)O₃-Pb(In,Nb)O₃ Piezoelectric Ceramics.

Figure of merit the product of piezoelectric charge constant and the piezoelectric voltage constant-d × g in piezoelectric energy harvesting systems are critical measures in energy harvester applications. It is difficult to achieve high figure of merit because of the interdependence of d and the relative dielectric constant, ε. Until now, the prohibitive amount of effort required to solve this problem has led to it being considered an unsolvable issue.

Enhanced Energy Efficiency of Light Grid System with Optimized System Design and Recycling with Thermoelectric Platform.

In this work, a light grid system with a high-power LED chip was manufactured and employed to analyze the energy efficiency of output optical energy. The high-power LED system based on thermoelectric modules, a heat dissipation structure and optical transmission system with an optical fiber were optimally combined and designed, which increased the efficiency of light grid system. Additionally, by introducing an effective design for the heat dissipation structure, the output optical energy and recycled electrical energy were increased.

Improved Multilayered (Bi,Sc)O-(Pb,Ti)O Piezoelectric Energy Harvesters Based on Impedance Matching Technique.

As a piezoelectric material, (Bi,Sc)O-(Pb,Ti)O ceramics have been tested and analyzed for sensors and energy harvester applications owing to their relatively high Curie temperature and high piezoelectric coefficient. In this work, we prepared optimized (Bi,Sc)O-(Pb,Ti)O piezoelectric materials through the conventional ceramic process. To increase the output energy, a multilayered structure was proposed and designed, and to obtain the maximum output energy, impedance matching techniques were considered and tested.

Selective Chemical Modulation of Interlayer Excitons in Atomically Thin Heterostructures.

Strongly bound interlayer excitons (Xs) in atomically thin transition metal dichalcogenide (TMDC) heterostructures such as MoS/WSe show promising optoelectronic properties for spin-valleytronics and excitonic devices. The ability to probe and control Xs is critical for the development of such applications. This Letter introduces a versatile chemical method for selectively tailoring interlayer excitons in TMDC heterostructures.

Enhanced Electrical Properties of Platinum Spotted AZO/PET Thin Films Prepared by Sol-Gel Process.

Recently, many researches on Al-doped ZnO (AZO) thin film based transparent conducting oxide (TCO) have been intensively investigated for the electronic and display device applications. In this study, AZO thin films with different thicknesses were deposited on polyethylene terephthalate (PET) substrates by sol-gel spin coating at a relatively low temperature. By optimizing the AZO thickness, maximum figure of merit (FOM) values were investigated and discussed.

Possibility of Thermal Energy Recycling Based Light Emitting Diodes Grid System.

Light Emitting Diodes (LED) are highly energy efficient and offer long-life times for display applications. Long life and minimal energy consumption are often the most attractive advantages for electronic devices. Because LEDs are based on compound semiconductors, which explore the direct transition between the conduction and valance band edges, thermal energy loss can be minimized during operation.

Relaxation-Related Piezoelectric and Dielectric Behavior of Bi(Mg,Ti)O⁻PbTiO Ceramic.

Piezoelectric and dielectric materials have attracted much attention for their functional device applications. Despite its excellent piezoelectric properties, the content of lead in piezoelectric materials should be restricted to prevent future environmental problems. Therefore, reduced lead content in piezoelectric materials with similar piezoelectric properties is favorable.

Microhomology Selection for Microhomology Mediated End Joining in .

Microhomology-mediated end joining (MMEJ) anneals short, imperfect microhomologies flanking DNA breaks, producing repair products with deletions in a Ku- and -independent fashion. Puzzlingly, MMEJ preferentially selects certain microhomologies over others, even when multiple microhomologies are available. To define rules and parameters for microhomology selection, we altered the length, the position, and the level of mismatches to the microhomologies flanking homothallic switching (HO) endonuclease-induced breaks and assessed their effect on MMEJ frequency and the types of repair product formation.

Pellino1 regulates reversible ATM activation via NBS1 ubiquitination at DNA double-strand breaks.

DNA double-strand break (DSB) signaling and repair are critical for genome integrity. They rely on highly coordinated processes including posttranslational modifications of proteins. Here we show that Pellino1 (Peli1) is a DSB-responsive ubiquitin ligase required for the accumulation of DNA damage response proteins and efficient homologous recombination (HR) repair.