Extensive homologous recombination safeguards oocyte genome integrity in mammals.

Meiosis in mammalian oocytes is interrupted by a prolonged arrest at the germinal vesicle stage, during which oocytes have to repair DNA lesions to ensure genome integrity or otherwise undergo apoptosis. The FIRRM/FLIP-FIGNL1 complex dissociates RAD51 from the joint DNA molecules in both homologous recombination (HR) and DNA replication. However, as a type of non-meiotic, non-replicative cells, whether this RAD51-dismantling mechanism regulates genome integrity in oocytes remains elusive.

Morphological Features Influence the Drug Loading and Delivery Efficacy of Photoactivatable Gold Nanocarriers for Antitumor Photo/Chemotherapy.

Photoactivatable gold nanocarriers are transforming antitumor therapies by leveraging their distinctive physicochemical properties, enabling targeted drug delivery and enhanced therapeutic efficacy in cancer treatment. This study systematically investigates how surface topography and morphology of gold nanocarriers influence drug loading capacity, light-to-heat conversion efficiency, and overall therapeutic performance in photo/chemotherapy. We synthesized four distinct morphologies of gold nanoparticles: porous gold nanocups (PAuNCs), porous gold nanospheres (PAuNSs), solid gold nanocups (SAuNCs), and solid gold nanospheres (SAuNSs).

New insights into the role of lipids in aroma formation during black tea processing revealed by integrated lipidomics and volatolomics.

Lipids are important tea aroma precursors. Due to the complexity of black tea processing involving both enzymatic and thermal reactions, the role of lipids in black tea aroma formation remained unclear. Herein, the dynamic changes of lipids and volatiles during black tea processing were simultaneously analyzed by lipidomics and volatolomics using ultra-high-performance liquid chromatography coupled to Q-Exactive Orbitrap mass spectrometry (UHPLC-Q-Exactive) and gas chromatography-tandem mass spectrometry (GC-MS/MS).

Biomimetic ROS-responsive hyaluronic acid nanoparticles loaded with methotrexate for targeted anti-atherosclerosis.

Atherosclerosis (AS), an inflammatory disease characterized by lipid accumulation, has a high global incidence and mortality rate. Recently, nanotherapeutic approaches that target pathological sites and improve drug bioavailability and biocompatibility hold great promise for AS treatment. In this study, a biomimetic ROS-responsive hyaluronic acid-based nanomaterial was prepared for targeted anti-AS.

Key umami taste contributors in Longjing green tea uncovered by integrated means of sensory quantitative descriptive analysis, metabolomics, quantification analysis and taste addition experiments.

Umami taste is a key criteria of green tea quality evaluation. The aim of this study was to comprehensively explore the key umami taste contributors in Longjing tea. The taste and molecular profiles of 36 Longjing green tea infusions were characterized by sensory quantitative descriptive analysis and LC-MS based metabolomics, respectively.

The FLIP-FIGNL1 complex regulates the dissociation of RAD51/DMC1 in homologous recombination and replication fork restart.

Recruitment of RAD51 and/or DMC1 recombinases to single-strand DNA is indispensable for homology search and strand invasion in homologous recombination (HR) and for protection of nascent DNA strands at stalled replication forks. Thereafter RAD51/DMC1 dissociate, actively or passively, from these joint molecules upon DNA repair or releasing from replication stress. However, the mechanism that regulates RAD51/DMC1 dissociation and its physiological importance remain elusive.

BBOF1 is required for sperm motility and male fertility by stabilizing the flagellar axoneme in mice.

The sperm flagellum is a specialized type of motile cilium composed of a typical "9 + 2" axonemal structure with peri-axonemal structures, such as outer dense fibers (ODFs). This flagellar arrangement is crucial for sperm movement and fertilization. However, the association of axonemal integrity with ODFs remains poorly understood.

Effects of exercise in treating patients with venous leg ulcers: A systematic review and meta-analysis.

To determine the effects of exercise on VLU healing and exercise adherence, and to provide evidence for clinical practice and scientific investigation. PubMed, Embase and Scopus were searched from inception to 31st March, 2022. Pooled relative risks (RRs), standardised mean differences (SMDs), adherence rate with respective 95% confidence intervals (CIs) were calculated.

Dye-cored polylysine dendrimer as luminescent nanoplatform for imaging-guided anticancer drug delivery.

Dendrimers have numerous applications in imaging and drug delivery. Designing a dendrimer diagnostic platform with a well-defined structure and controlled drug delivery is a formidable challenge. Here, we design dendritic polymer-platinum conjugates (G5-PEG-Pt) as pH-responsive nanovesicles for imaging-guided platinum drug delivery.

Investigating the effect of three phenolic fractions on the volatility of floral, fruity, and aged aromas by HS-SPME-GC-MS and NMR in model wine.

In this study, the volatility of three typical wine aromas in model wine was investigated by HS-SPME-GC-MS, NMR, and sensory evaluation as influenced by different concentrations and structural properties of phenolics. Results showed that three phenolic fractions (phenolic acids, monomeric/oligomeric and polymeric procyanidins) exhibited different matrix effects on floral, fruity, and aged aromas perception. Physico-chemical and sensory analyses together indicated that all fractions reduced the perceived intensity of fruity and aged aroma attributes, and displayed stronger retention effects on fruity aromas at higher mDP and concentrations.

Ubiquitin-Proteasome System-Regulated Protein Degradation in Spermatogenesis.

Spermatogenesis is a prolonged and highly ordered physiological process that produces haploid male germ cells through more than 40 steps and experiences dramatic morphological and cellular transformations. The ubiquitin proteasome system (UPS) plays central roles in the precise control of protein homeostasis to ensure the effectiveness of certain protein groups at a given stage and the inactivation of them after this stage. Many UPS components have been demonstrated to regulate the progression of spermatogenesis at different levels.

Wine polysaccharides modulating astringency through the interference on interaction of flavan-3-ols and BSA in model wine.

Polysaccharides and flavan-3-ols from Cabernet Sauvignon wine were isolated and then characterized by high performance liquid chromatography coupled with diode array detector (HPLC-DAD), high performance size exclusion chromatography (HPSEC) and HPLC-MS. The influence of purified polysaccharides on the aggregation of flavan-3-ols-proteins were investigated using fluorescence spectroscopy, circular dichroism (CD) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) to evaluate the co-effect of polysaccharides on wine astringency. The results indicated that mannoproteins (MPs) and rhamnogalacturonans II (RG II) were the major polysaccharides to significantly alter the interaction of flavan-3-ols with bovine serum albumin (BSA).

Meiosis I progression in spermatogenesis requires a type of testis-specific 20S core proteasome.

Spermatogenesis is tightly regulated by ubiquitination and proteasomal degradation, especially during spermiogenesis, in which histones are replaced by protamine. However, the functions of proteasomal activity in meiosis I and II remain elusive. Here, we show that PSMA8-associated proteasomes are essential for the degradation of meiotic proteins and the progression of meiosis I during spermatogenesis.

SPO16 binds SHOC1 to promote homologous recombination and crossing-over in meiotic prophase I.

Segregation of homologous chromosomes in meiosis I is tightly regulated by their physical links, or crossovers (COs), generated from DNA double-strand breaks (DSBs) through meiotic homologous recombination. In budding yeast, three ZMM (Zip1/2/3/4, Mer3, Msh4/5) proteins, Zip2, Zip4, and Spo16, form a "ZZS" complex, functioning to promote meiotic recombination via a DSB repair pathway. Here, we identified the mammalian ortholog of Spo16, termed SPO16, which interacts with the mammalian ortholog of Zip2 (SHOC1/MZIP2), and whose functions are evolutionarily conserved to promote the formation of COs.

ALK phosphorylates SMAD4 on tyrosine to disable TGF-β tumour suppressor functions.

Loss of TGF-β tumour suppressive response is a hallmark of human cancers. As a central player in TGF-β signal transduction, SMAD4 (also known as DPC4) is frequently mutated or deleted in gastrointestinal and pancreatic cancer. However, such genetic alterations are rare in most cancer types and the underlying mechanism for TGF-β resistance is not understood.

Evolutionarily-conserved MZIP2 is essential for crossover formation in mammalian meiosis.

During meiosis, formation of crossovers-the physical links that ensure the segregation of homologous chromosomes-requires a group of evolutionarily conserved ZMM proteins. In budding yeast, three ZMM proteins, Zip2, Spo16, and Zip4, form a trimeric complex to bind recombination intermediates and promote crossover formation. Here, we show that MZIP2 is the mammalian ortholog of Zip2.