Biochemistry and Cell Biology最新文献

The 2'-5'-oligoadenylate synthetases (OAS) are important components of the innate immune system that recognize viral double-stranded RNA (dsRNA). Upon dsRNA binding, OAS generate 2'-5'-linked oligoadenylates (2-5A) that activate ribonuclease L (RNase L), halting viral replication. The OAS/RNase L pathway is thus an important antiviral pathway and viruses have devised strategies to circumvent OAS activation. OAS enzymes are divided into four classes according to size: small (OAS1), medium (OAS2), and large (OAS3) that consist of one, two, and three OAS domains, respectively, and the OAS-like protein (OASL) that consists of one OAS domain and tandem domains similar to ubiquitin. Early investigation of the OAS enzymes hinted at the recognition of dsRNA by OAS, but due to size differences amongst OAS family members combined with the lack of structural information on full-length OAS2 and OAS3, the regulation of OAS catalytic activity by dsRNA was not well understood. However, the recent biophysical studies of OAS have highlighted overall structure and domain organization. In this review, we present a detailed examination of the OAS literature and summarized the investigation on 2'-5'-oligoadenylate synthetases.

Interstitial cystitis (IC), defined as a painful bladder syndrome (PBS), is a chronic condition that manifests itself as a suprapubic pain associated with an enhancing of frequency/urgency of urination, and for which there is no cure. Here, we present a retrospective pilot study on women affected from IC/PBS and treated with bovine lactoferrin (bLf). A total of 31 women, affected (20) or unaffected (11) from hereditary thrombophilia (HT), presented the median of 6 episodes of IC/PBS during the 6 months before the study. Treatment consisted of 17 weeks of orally administered Valpalf^® capsules, containing bLf plus sodium bicarbonate and citrate. Out of 31 patients, only 3 women had one episode of IC/PBS during the follow-up period, while no episode was observed in 28 women. In the HT group, a significant decrease in both serum IL-6 and D-dimers was found after Valpalf^® treatment. Moreover, in Valpalf^®-treated women, cystoscopy revealed a global improvement in the appearance of the bladder, especially in term of inflammation/irritation and presence of Hunner ulcers. Even if our results must be corroborated by randomized double-blinded controlled trials on a larger number of patients, our observations indicate that bLf treatment is efficient in relieving IC/PBS symptoms, without side effects.

I was fortunate enough to start my career at what was the dawn of modern-day molecular biology and to apply it to an important health problem. While my early work focused on fundamental science, the desire to understand human disease better and to find practical applications for research discoveries resulted, over the following decades, in creating a stream of translational research directed specifically toward epithelial cancers. This could only have been possible through multiple collaborations. This type of team science would eventually become a hallmark of my career. With the development of higher throughput molecular techniques, the pace of research and discovery has quickened, and the concept of personalized medicine based on genomics is now coming to fruition. I hope my legacy will not just reflect my published works, but will also include the impact I have had on the development of the next generation of scientists and clinician scientists who inspired me with their dedication, knowledge, and enthusiasm.

Lipocalin-2 (LCN2), an effector molecule of the innate immune system that is small enough to be tagged as a reporter molecule, can be coupled with the ferric ion through a siderophore such as enterobactin (Ent). Mintbody (modification-specific intracellular antibody) can track a posttranslational protein modification in epigenetics. We constructed plasmids expressing the LCN2 hybrid of mintbody to examine the potential of LCN2 as a novel reporter for magnetic resonance imaging (MRI). Cells expressing the LCN2 hybrid of mintbody showed proper expression and localization of the hybrid and responded reasonably to Ent, suggesting their potential for in vivo study by MRI.

Ferroptosis has been regarded as a critical event in the process of diffuse large B cell lymphoma (DLBCL). Sentrin-specific protease 1 (SENP1) has emerged as an oncogene in multiple human malignancies. The present work was to investigate the effects of SENP1 on the progression of DLBCL and the possible regulatory mechanism involving ferroptosis. SENP1 expression in DLBCL tissues, parental and cisplatin-resistant DLBCL cells were, respectively, tested by GEPIA database, RT-qPCR, and Western blot. Cell viability was estimated via CCK-8 assay. Flow cytometry analysis estimated cell apoptosis and cycle. Western blot examined the expression of apoptosis-, cell cycle-, and ferroptosis-associated proteins. TBARS assay and BODIPY 581/591 C11 probe measured lipid peroxidation. Related assay kit assessed total iron levels. CCK-8 and flow cytometry evaluated cisplatin resistance. SENP1 expression was raised in DLBCL tissues and cells. SENP1 knockdown reduced cell viability, boosted cell apoptosis, cell cycle arrest, and elevated cisplatin sensitivity in DLBCL. SENP1 depletion drove the ferroptosis of both parental and cisplatin-resistant DLBCL cells and ferroptosis inhibitor Fer-1 reversed the influences of SENP1 inhibition on cell viability, apoptosis, cell cycle, and cisplatin resistance in DLBCL. Anyway, SENP1 absence might facilitate ferroptosis to obstruct the development of DLBCL and cisplatin resistance.

We previously found that the position of matrix attachment regions (MARs) within the vector significantly affects its ability to enhance transgenic expression in the recombinant protein production. This study aims to systematically investigate the position-dependent impacts of MAR on transgene expression. We observed a significant increase in enhanced green fluorescent protein (eGFP) expression levels in stably transfected CHO-K1 cells with either MAR 1-68 or MAR X-29 when MARs located upstream of the promoter. This increase was especially evident with MAR flanked the expression cassette. Concurrently, a substantial increase was observed in the percentage of eGFP-expressing cells, with 97.8% and 96.0% in MAR-containing constructs versus 73.7% in MAR-absent constructs. Further analysis of erythropoietin (EPO) expression revealed that constructs with flanking MARs induced the highest EPO productivity. Bioinformatics analysis revealed that certain specific transcription factors are important in modulating the transcription process. In conclusion, vectors harboring both MARs around the expression cassette constitute an optimal construct for enhanced recombinant protein production in CHO-K1 cells. This insight underscores the importance of strategic MAR incorporation in vector design for optimized recombinant protein expression.

Atherosclerosis (AS) is an inflammatory arterial disorder that occurs due to the deposition of the excessive lipoprotein under the artery intima, mainly including low-density lipoprotein and other apolipoprotein B-containing lipoproteins. G protein-coupled receptors (GPCRs) play a crucial role in transmitting signals in physiological and pathophysiological conditions. GPCRs recognize inflammatory mediators, thereby serving as important players during chronic inflammatory processes. It has been demonstrated that free fatty acids can function as ligands for various GPCRs, such as free fatty acid receptor (FFAR)1/GPR40, FFAR2/GPR43, FFAR3/GPR41, FFAR4/GPR120, and the lipid metabolite binding glucose-dependent insulinotropic receptor (GPR119). This review discusses GPR43 and its ligands in the pathogenesis of AS, especially focusing on its distinct role in regulating chronic vascular inflammation, inhibiting oxidative stress, ameliorating endothelial dysfunction and improving dyslipidemia. It is hoped that this review may provide guidance for further studies aimed at GPR43 as a promising target for drug development in the prevention and therapy of AS.

Over the past four decades, prion diseases have received considerable research attention owing to their potential to be transmitted within and across species as well as their consequences for human and animal health. The unprecedented nature of prions has led to the discovery of a paradigm of templated protein misfolding that underlies a diverse range of both disease-related and normal biological processes. Indeed, the "prion-like" misfolding and propagation of protein aggregates is now recognized as a common underlying disease mechanism in human neurodegenerative disorders such as Alzheimer's and Parkinson's disease, and the prion principle has led to the development of novel diagnostic and therapeutic strategies for these illnesses. Despite these advances, research into the fundamental biology of prion diseases has declined, likely due to their rarity and the absence of an acute human health crisis. Given the past translational influence, continued research on the etiology, pathogenesis, and transmission of prion disease should remain a priority. In this review, we highlight several important "unsolved mysteries" in the prion disease research field and how solving them may be crucial for the development of effective therapeutics, preventing future outbreaks of prion disease, and understanding the pathobiology of more common human neurodegenerative disorders.

We here describe the structure-based design of small molecule inhibitors of the type IV secretion system of Helicobacter pylori. The secretion system is encoded by the cag pathogenicity island, and we chose Cagα, a hexameric ATPase and member of the family of VirB11-like proteins, as target for inhibitor design. We first solved the crystal structure of Cagα in a complex with the previously identified small molecule inhibitor 1G2. The molecule binds at the interface between two Cagα subunits and mutagenesis of the binding site identified Cagα residues F39 and R73 as critical for 1G2 binding. Based on the inhibitor binding site we synthesized 98 small molecule derivates of 1G2 to improve binding of the inhibitor. We used the production of interleukin-8 of gastric cancer cells during H. pylori infection to screen the potency of inhibitors and we identified five molecules (1G2_1313, 1G2_1338, 1G2_2886, 1G2_2889, and 1G2_2902) that have similar or higher potency than 1G2. Differential scanning fluorimetry suggested that these five molecules bind Cagα, and enzyme assays demonstrated that some are more potent ATPase inhibitors than 1G2. Finally, scanning electron microscopy revealed that 1G2 and its derivatives inhibit the assembly of T4SS-determined extracellular pili suggesting a mechanism for their anti-virulence effect.

Sperm nuclear basic proteins (SNBPs) were isolated from extracted antheridia-rich male gametophytes raised from spores of the swordfern, Polystichum munitum. Electrophoretic (acetic acid-urea PAGE and SDS-PAGE) and chromatographic (rp-HPLC) characterization of the nuclear proteins exhibited the characteristics of the histone (H-type). In both types of gel electrophoresis, histones H1, H2A, and H2B showed an altered electrophoretic mobility corresponding to that which is routinely observed for the histones in other plants. Histones present during spermatogenesis of the fern P. munitum were compared with the few current SNBPs known to be present in higher and lower evolutionary plant clades. A transition from an early protamine (P-type) SNBPs in charophytes and bryophytes to the (H-type) SNBP observed here is reminiscent of similar reversions observed in the animal kingdom.