Development and application of an uncapped mRNA platform

BACKGROUND

A novel uncapped mRNA platform was developed.

METHODS

Five lipid nanoparticle (LNP)-encapsulated mRNA constructs were made to evaluate several aspects of our platform, including transfection efficiency and durability in vitro and in vivo and the activation of humoral and cellular immunity in several animal models. The constructs were eGFP-mRNA-LNP (for enhanced green fluorescence mRNA), Fluc-mRNA-LNP (for firefly luciferase mRNA), SδT-mRNA-LNP (for Delta strain SARS-CoV-2 spike protein trimer mRNA), gDED-mRNA-LNP (for truncated glycoprotein D mRNA coding ectodomain from herpes simplex virus type 2 (HSV2)) and gDFR-mRNA-LNP (for truncated HSV2 glycoprotein D mRNA coding amino acids 1-400).

RESULTS

Quantifiable target protein expression was achieved in vitro and in vivo with eGFP- and Fluc-mRNA-LNP. SδT-mRNA-LNP, gDED-mRNA-LNP and gDFR-mRNA-LNP induced both humoral and cellular immune responses comparable to those obtained by previously reported capped mRNA-LNP constructs. Notably, SδT-mRNA-LNP elicited neutralizing antibodies in hamsters against the Omicron and Delta strains. Additionally, gDED-mRNA-LNP and gDFR-mRNA-LNP induced potent neutralizing antibodies in rabbits and mice. The mRNA constructs with uridine triphosphate (UTP) outperformed those with N1-methylpseudouridine triphosphate (N1mψTP) in the induction of antibodies via SδT-mRNA-LNP.

CONCLUSIONS

Our uncapped, process-simplified and economical mRNA platform may have broad utility in vaccines and protein replacement drugs.KEY MESSAGESThe mRNA platform described in our paper uses internal ribosome entry site (IRES) (Rapid, Amplified, Capless and Economical, RACE; Register as BH-RACE platform) instead of caps and uridine triphosphate (UTP) instead of N1-methylpseudouridine triphosphate (N1mψTP) to synthesize mRNA.Through the self-developed packaging instrument and lipid nanoparticle (LNP) delivery system, mRNA can be expressed in cells more efficiently, quickly and economically.Particularly exciting is that potent neutralizing antibodies against Delta and Omicron real viruses were induced with the new coronavirus S protein mRNA vaccine from the BH-RACE platform.

A fast in situ hybridization chain reaction method in Drosophila embryos and ovaries

The in situ hybridization chain reaction (isHCR) is a powerful method for visualizing mRNA in many species. We present a rapid isHCR method for Drosophila embryos and ovaries. Ethylene carbonate was added to the hybridization buffer to facilitate the hybridization reaction, and a modified short hairpin DNA was used in the amplification reaction; these modifications decreased the RNA staining time from 3 days to 1 day. This method is compatible with immunohistochemistry and can detect multiple mRNAs. The proposed method could significantly reduce staining time for Drosophila researchers using isHCR.

Hyperdifferentiated murine melanoma cells promote adaptive anti-tumor immunity but activate the immune checkpoint system

Accumulating evidence suggests that phenotype switching of cancer cells is essential for therapeutic resistance. However, the immunological characteristics of drug-induced phenotype-switching melanoma cells (PSMCs) are unknown. We investigated PSMC elimination by host immunity using hyperdifferentiated melanoma model cells derived from murine B16F10 melanoma cells. Exposure of B16F10 cells to staurosporine induced a hyperdifferentiated phenotype associated with transient drug tolerance. Staurosporine-induced hyperdifferentiated B16F10 (sB16F10) cells expressed calreticulin on their surface and were phagocytosed efficiently. Furthermore, the inoculation of mice with sB16F10 cells induced immune responses against tumor-derived antigens. Despite the immunogenicity of sB16F10 cells, they activated the PD-1/PD-L1 immune checkpoint system and strongly resisted T cell-mediated tumor destruction. However, in vivo treatment with immune checkpoint inhibitors successfully eliminated the tumor. Thus, hyperdifferentiated melanoma cells have conflicting immunological properties - enhanced immunogenicity and immune evasion. Inhibiting the ability of PSMCs to evade T cell-mediated elimination might lead to complete melanoma eradication.

Haematologic outcomes and associated clinical characteristics among patients receiving Olaparib therapy in the UAE: a retrospective chart review

BACKGROUND

Poly ADP ribose polymerase (PARP) inhibitors, such as Olaparib (Lynparza®), are pivotal in treating certain cancers, particularly those linked to BReast CAncer gene (BRCA) mutations. Despite its established efficacy, Olaparib use is associated with various adverse events (AEs), notably haematologic toxicities, such as anaemia. This retrospective chart review study aimed to examine haematologic outcomes and associated factors in patients treated with Olaparib at a tertiary hospital in the UAE.

METHODS

We reviewed the medical charts of patients prescribed Olaparib and focused on haematologic indices at a baseline of 1-month, 3-month and 6-month follow-up periods. Data were analysed to determine the AEs frequency, transfusions need and potential associated patients' clinical characteristics.

RESULTS

This study included all patients who received Olaparib (n = 66). Most patients were females (n = 61; 92.4%) and the vast majority were non-smokers (97%) and free of hepatic disease. Themean age of the patients was 57.03-year-old (SD) = 12.06 years), and body mass index (BMI) was 28.16 (SD = 6.40) kg/m2. A high rate of anaemia (70.8%) was detected among the patients during their Olaparib therapy. Approximately, one-third of the patients developed neutropenia and thrombocytopenia. Transfusion was needed in almost half of the patients. Glomerular filtration rate (GFR) and neutropenia were significantly correlated with moderate-severe anaemia (OR = 0.097, 95% CI: 0.011-0.88, p value = .038) and (OR = 9.04, 95% CI: 1.024-79.78, p value = .048), respectively.

CONCLUSIONS

Our findings highlight the side effects of Olaparib therapy in terms of haematology which could be avoided. Further studies are needed to better understand the therapeutic management of Olaparib and the mitigation of haematologic complications.

Nanocarrier-mediated siRNA delivery: a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

Traumatic brain injury and Alzheimer's disease share pathological similarities, including neuronal loss, amyloid-β deposition, tau hyperphosphorylation, blood-brain barrier dysfunction, neuroinflammation, and cognitive deficits. Furthermore, traumatic brain injury can exacerbate Alzheimer's disease-like pathologies, potentially leading to the development of Alzheimer's disease. Nanocarriers offer a potential solution by facilitating the delivery of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease. Unlike traditional approaches to neuroregeneration, this is a molecular-targeted strategy, thus avoiding non-specific drug actions. This review focuses on the use of nanocarrier systems for the efficient and precise delivery of siRNAs, discussing the advantages, challenges, and future directions. In principle, siRNAs have the potential to target all genes and non-targetable proteins, holding significant promise for treating various diseases. Among the various therapeutic approaches currently available for neurological diseases, siRNA gene silencing can precisely "turn off" the expression of any gene at the genetic level, thus radically inhibiting disease progression; however, a significant challenge lies in delivering siRNAs across the blood-brain barrier. Nanoparticles have received increasing attention as an innovative drug delivery tool for the treatment of brain diseases. They are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier, targeted drug delivery, enhanced drug stability, and multifunctional therapy. The use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective approach. Although this strategy is still in the preclinical exploration stage, it is expected to achieve clinical translation in the future, creating a new field of molecular targeted therapy and precision medicine for the treatment of Alzheimer's disease associated with traumatic brain injury.

Crosstalk among canonical Wnt and Hippo pathway members in skeletal muscle and at the neuromuscular junction

Skeletal muscles are essential for locomotion, posture, and metabolic regulation. To understand physiological processes, exercise adaptation, and muscle-related disorders, it is critical to understand the molecular pathways that underlie skeletal muscle function. The process of muscle contraction, orchestrated by a complex interplay of molecular events, is at the core of skeletal muscle function. Muscle contraction is initiated by an action potential and neuromuscular transmission requiring a neuromuscular junction. Within muscle fibers, calcium ions play a critical role in mediating the interaction between actin and myosin filaments that generate force. Regulation of calcium release from the sarcoplasmic reticulum plays a key role in excitation-contraction coupling. The development and growth of skeletal muscle are regulated by a network of molecular pathways collectively known as myogenesis. Myogenic regulators coordinate the differentiation of myoblasts into mature muscle fibers. Signaling pathways regulate muscle protein synthesis and hypertrophy in response to mechanical stimuli and nutrient availability. Several muscle-related diseases, including congenital myasthenic disorders, sarcopenia, muscular dystrophies, and metabolic myopathies, are underpinned by dysregulated molecular pathways in skeletal muscle. Therapeutic interventions aimed at preserving muscle mass and function, enhancing regeneration, and improving metabolic health hold promise by targeting specific molecular pathways. Other molecular signaling pathways in skeletal muscle include the canonical Wnt signaling pathway, a critical regulator of myogenesis, muscle regeneration, and metabolic function, and the Hippo signaling pathway. In recent years, more details have been uncovered about the role of these two pathways during myogenesis and in developing and adult skeletal muscle fibers, and at the neuromuscular junction. In fact, research in the last few years now suggests that these two signaling pathways are interconnected and that they jointly control physiological and pathophysiological processes in muscle fibers. In this review, we will summarize and discuss the data on these two pathways, focusing on their concerted action next to their contribution to skeletal muscle biology. However, an in-depth discussion of the non-canonical Wnt pathway, the fibro/adipogenic precursors, or the mechanosensory aspects of these pathways is not the focus of this review.

Neuroprotective potential for mitigating ischemia-reperfusion-induced damage

Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition; this phenomenon is known as cerebral ischemia-reperfusion injury. Current studies have elucidated the neuroprotective role of the sirtuin protein family (Sirtuins) in modulating cerebral ischemia-reperfusion injury. However, the potential of utilizing it as a novel intervention target to influence the prognosis of cerebral ischemia-reperfusion injury requires additional exploration. In this review, the origin and research progress of Sirtuins are summarized, suggesting the involvement of Sirtuins in diverse mechanisms that affect cerebral ischemia-reperfusion injury, including inflammation, oxidative stress, blood-brain barrier damage, apoptosis, pyroptosis, and autophagy. The therapeutic avenues related to Sirtuins that may improve the prognosis of cerebral ischemia-reperfusion injury were also investigated by modulating Sirtuins expression and affecting representative pathways, such as nuclear factor-kappa B signaling, oxidative stress mediated by adenosine monophosphate-activated protein kinase, and the forkhead box O. This review also summarizes the potential of endogenous substances, such as RNA and hormones, drugs, dietary supplements, and emerging therapies that regulate Sirtuins expression. This review also reveals that regulating Sirtuins mitigates cerebral ischemia-reperfusion injury when combined with other risk factors. While Sirtuins show promise as a potential target for the treatment of cerebral ischemia-reperfusion injury, most recent studies are based on rodent models with circadian rhythms that are distinct from those of humans, potentially influencing the efficacy of Sirtuins-targeting drug therapies. Overall, this review provides new insights into the role of Sirtuins in the pathology and treatment of cerebral ischemia-reperfusion injury.

Neuronal regulated cell death in aging-related neurodegenerative diseases: key pathways and therapeutic potentials

Regulated cell death (such as apoptosis, necroptosis, pyroptosis, autophagy, cuproptosis, ferroptosis, disulfidptosis) involves complex signaling pathways and molecular effectors, and has been proven to be an important regulatory mechanism for regulating neuronal aging and death. However, excessive activation of regulated cell death may lead to the progression of aging-related diseases. This review summarizes recent advances in the understanding of seven forms of regulated cell death in age-related diseases. Notably, the newly identified ferroptosis and cuproptosis have been implicated in the risk of cognitive impairment and neurodegenerative diseases. These forms of cell death exacerbate disease progression by promoting inflammation, oxidative stress, and pathological protein aggregation. The review also provides an overview of key signaling pathways and crosstalk mechanisms among these regulated cell death forms, with a focus on ferroptosis, cuproptosis, and disulfidptosis. For instance, FDX1 directly induces cuproptosis by regulating copper ion valency and dihydrolipoamide S-acetyltransferase aggregation, while copper mediates glutathione peroxidase 4 degradation, enhancing ferroptosis sensitivity. Additionally, inhibiting the Xc- transport system to prevent ferroptosis can increase disulfide formation and shift the NADP + /NADPH ratio, transitioning ferroptosis to disulfidptosis. These insights help to uncover the potential connections among these novel regulated cell death forms and differentiate them from traditional regulated cell death mechanisms. In conclusion, identifying key targets and their crosstalk points among various regulated cell death pathways may aid in developing specific biomarkers to reverse the aging clock and treat age-related neurodegenerative conditions.

EZH2-dependent myelination following sciatic nerve injury

JOURNAL/nrgr/04.03/01300535-202508000-00028/figure1/v/2024-09-30T120553Z/r/image-tiff Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve injury. Notably, the gene regulatory network of regenerated myelin differs from that of native myelin. Silencing of enhancer of zeste homolog 2 (EZH2) hinders the differentiation, maturation, and myelination of Schwann cells in vitro. To further determine the role of EZH2 in myelination and recovery post-peripheral nerve injury, conditional knockout mice lacking Ezh2 in Schwann cells (Ezh2fl/fl;Dhh-Cre and Ezh2fl/fl;Mpz-Cre) were generated. Our results show that a significant proportion of axons in the sciatic nerve of Ezh2-depleted mice remain unmyelinated. This highlights the crucial role of Ezh2 in initiating Schwann cell myelination. Furthermore, we observed that 21 days after inducing a sciatic nerve crush injury in these mice, most axons had remyelinated at the injury site in the control nerve, while Ezh2fl/fl;Mpz-Cre mice had significantly fewer remyelinated axons compared with their wild-type littermates. This suggests that the absence of Ezh2 in Schwann cells impairs myelin formation and remyelination. In conclusion, EZH2 has emerged as a pivotal regulatory factor in the process of demyelination and myelin regeneration following peripheral nerve injury. Modulating EZH2 activity during these processes may offer a promising therapeutic target for the treatment of peripheral nerve injuries.

Interaction of major facilitator superfamily domain containing 2A with the blood-brain barrier

The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment; however, the molecular mechanisms underlying the formation and function of the blood-brain barrier remain poorly understood. The major facilitator superfamily domain containing 2A has been identified as a key regulator of blood-brain barrier function. It plays a critical role in promoting and maintaining the formation and functional stability of the blood-brain barrier, in addition to the transport of lipids, such as docosahexaenoic acid, across the blood-brain barrier. Furthermore, an increasing number of studies have suggested that major facilitator superfamily domain containing 2A is involved in the molecular mechanisms of blood-brain barrier dysfunction in a variety of neurological diseases; however, little is known regarding the mechanisms by which major facilitator superfamily domain containing 2A affects the blood-brain barrier. This paper provides a comprehensive and systematic review of the close relationship between major facilitator superfamily domain containing 2A proteins and the blood-brain barrier, including their basic structures and functions, cross-linking between major facilitator superfamily domain containing 2A and the blood-brain barrier, and the in-depth studies on lipid transport and the regulation of blood-brain barrier permeability. This comprehensive systematic review contributes to an in-depth understanding of the important role of major facilitator superfamily domain containing 2A proteins in maintaining the structure and function of the blood-brain barrier and the research progress to date. This will not only help to elucidate the pathogenesis of neurological diseases, improve the accuracy of laboratory diagnosis, and optimize clinical treatment strategies, but it may also play an important role in prognostic monitoring. In addition, the effects of major facilitator superfamily domain containing 2A on blood-brain barrier leakage in various diseases and the research progress on cross-blood-brain barrier drug delivery are summarized. This review may contribute to the development of new approaches for the treatment of neurological diseases.

FUBP3 mediates the amyloid-β-induced neuronal NLRP3 expression

JOURNAL/nrgr/04.03/01300535-202507000-00028/figure1/v/2024-09-09T124005Z/r/image-tiff Alzheimer's disease is characterized by deposition of amyloid-β, which forms extracellular neuritic plaques, and accumulation of hyperphosphorylated tau, which aggregates to form intraneuronal neurofibrillary tangles, in the brain. The NLRP3 inflammasome may play a role in the transition from amyloid-β deposition to tau phosphorylation and aggregation. Because NLRP3 is primarily found in brain microglia, and tau is predominantly located in neurons, it has been suggested that NLRP3 expressed by microglia indirectly triggers tau phosphorylation by upregulating the expression of pro-inflammatory cytokines. Here, we found that neurons also express NLRP3 in vitro and in vivo, and that neuronal NLRP3 regulates tau phosphorylation. Using biochemical methods, we mapped the minimal NLRP3 promoter and identified FUBP3 as a transcription factor regulating NLRP3 expression in neurons. In primary neurons and the neuroblastoma cell line Neuro2A, FUBP3 is required for endogenous NLRP3 expression and tau phosphorylation only when amyloid-β is present. In the brains of aged wild-type mice and a mouse model of Alzheimer's disease, FUBP3 expression was markedly increased in cortical neurons. Transcriptome analysis suggested that FUBP3 plays a role in neuron-mediated immune responses. We also found that FUBP3 trimmed the 5' end of DNA fragments that it bound, implying that FUBP3 functions in stress-induced responses. These findings suggest that neuronal NLRP3 may be more directly involved in the amyloid-β-to-phospho-tau transition than microglial NLRP3, and that amyloid-β fundamentally alters the regulatory mechanism of NLRP3 expression in neurons. Given that FUBP3 was only expressed at low levels in young wild-type mice and was strongly upregulated in the brains of aged mice and Alzheimer's disease mice, FUBP3 could be a safe therapeutic target for preventing Alzheimer's disease progression.

Perilipin-2 mediates ferroptosis in oligodendrocyte progenitor cells and myelin injury after ischemic stroke

JOURNAL/nrgr/04.03/01300535-202507000-00024/figure1/v/2024-09-09T124005Z/r/image-tiff Differentiation of oligodendrocyte progenitor cells into mature myelin-forming oligodendrocytes contributes to remyelination. Failure of remyelination due to oligodendrocyte progenitor cell death can result in severe nerve damage. Ferroptosis is an iron-dependent form of regulated cell death caused by membrane rupture induced by lipid peroxidation, and plays an important role in the pathological process of ischemic stroke. However, there are few studies on oligodendrocyte progenitor cell ferroptosis. We analyzed transcriptome sequencing data from GEO databases and identified a role of ferroptosis in oligodendrocyte progenitor cell death and myelin injury after cerebral ischemia. Bioinformatics analysis suggested that perilipin-2 (PLIN2) was involved in oligodendrocyte progenitor cell ferroptosis. PLIN2 is a lipid storage protein and a marker of hypoxia-sensitive lipid droplet accumulation. For further investigation, we established a mouse model of cerebral ischemia/reperfusion. We found significant myelin damage after cerebral ischemia, as well as oligodendrocyte progenitor cell death and increased lipid peroxidation levels around the infarct area. The ferroptosis inhibitor, ferrostatin-1, rescued oligodendrocyte progenitor cell death and subsequent myelin injury. We also found increased PLIN2 levels in the peri-infarct area that co-localized with oligodendrocyte progenitor cells. Plin2 knockdown rescued demyelination and improved neurological deficits. Our findings suggest that targeting PLIN2 to regulate oligodendrocyte progenitor cell ferroptosis may be a potential therapeutic strategy for rescuing myelin damage after cerebral ischemia.

NOX4 exacerbates Parkinson's disease pathology by promoting neuronal ferroptosis and neuroinflammation

JOURNAL/nrgr/04.03/01300535-202507000-00026/figure1/v/2024-09-09T124005Z/r/image-tiff Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra compacta. Ferroptosis, a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation, plays a vital role in the death of dopaminergic neurons. However, the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely elucidated. NADPH oxidase 4 is related to oxidative stress, however, whether it regulates dopaminergic neuronal ferroptosis remains unknown. The aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis, and if so, by what mechanism. We found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease model. NADPH oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic neurons. Moreover, NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model animals. Mechanistically, we found that NADPH oxidase 4 interacted with activated protein kinase C α to prevent ferroptosis of dopaminergic neurons. Furthermore, by lowering the astrocytic lipocalin-2 expression, NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced neuroinflammation. These findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation, which contribute to dopaminergic neuron death, suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.

MET receptor tyrosine kinase promotes the generation of functional synapses in adult cortical circuits

JOURNAL/nrgr/04.03/01300535-202505000-00026/figure1/v/2024-07-28T173839Z/r/image-tiff Loss of synapse and functional connectivity in brain circuits is associated with aging and neurodegeneration, however, few molecular mechanisms are known to intrinsically promote synaptogenesis or enhance synapse function. We have previously shown that MET receptor tyrosine kinase in the developing cortical circuits promotes dendritic growth and dendritic spine morphogenesis. To investigate whether enhancing MET in adult cortex has synapse regenerating potential, we created a knockin mouse line, in which the human MET gene expression and signaling can be turned on in adult (10-12 months) cortical neurons through doxycycline-containing chow. We found that similar to the developing brain, turning on MET signaling in the adult cortex activates small GTPases and increases spine density in prefrontal projection neurons. These findings are further corroborated by increased synaptic activity and transient generation of immature silent synapses. Prolonged MET signaling resulted in an increased α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid/N-methyl-D-aspartate (AMPA/NMDA) receptor current ratio, indicative of enhanced synaptic function and connectivity. Our data reveal that enhancing MET signaling could be an interventional approach to promote synaptogenesis and preserve functional connectivity in the adult brain. These findings may have implications for regenerative therapy in aging and neurodegeneration conditions.

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

JOURNAL/nrgr/04.03/01300535-202505000-00025/figure1/v/2024-07-28T173839Z/r/image-tiff Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair. We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling, influencing their activation such that they can promote neurological recovery. However, the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear. In this study, we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-α expression but suppressed insulin-like growth factor-1 expression. However, recombinant complement receptor 2-conjugated Crry (CR2-Crry) reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia, CXCL12, and tumor necrosis factor-α. Additionally, we observed that, in response to stimulation (including stimulation by CXCL12 secreted by activated microglia), CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4, Crry, and Akt signaling to modulate microglial activation. In agreement with these in vitro experimental results, we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation, leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice. Notably, these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury, cerebral edema, and neurological disorders post-closed head injury. In conclusion, our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry, thereby promoting induced neural stem cell-mediated improvement of neuronal injury, cerebral edema, and neurological disorders following closed head injury.

The role of nuclear factor erythroid 2-related factor 2 (NRF2) in arsenic toxicity

Arsenic, a naturally occurring toxic element, manifests in various chemical forms and is widespread in the environment. Exposure to arsenic is a well-established risk factor for an elevated incidence of various cancers and chronic diseases. The crux of arsenic-mediated toxicity lies in its ability to induce oxidative stress, characterized by an unsettling imbalance between oxidants and antioxidants, accompanied by the rampant generation of reactive oxygen species and free radicals. In response to this oxidative turmoil, cells deploy their defense mechanisms, prominently featuring the redox-sensitive transcription factor known as nuclear factor erythroid 2-related factor 2 (NRF2). NRF2 stands as a primary guardian against the oxidative harm wrought by arsenic. When oxidative stress activates NRF2, it orchestrates a symphony of downstream antioxidant genes, leading to the activation of pivotal antioxidant enzymes like glutathione-S-transferase, heme oxygenase-1, and NAD(P)H: quinone oxidoreductase 1. This comprehensive review embarks on the intricate and diverse ways by which various arsenicals influence the NRF2 antioxidant pathway and its downstream targets, shedding light on their roles in defending against arsenic exposure toxic effects. It offers valuable insights into targeting NRF2 as a strategy for safeguarding against or treating the harmful and carcinogenic consequences of arsenic exposure.

Targeting senescence with radioactive 223Ra/Ba SAzymes enables senolytics-unlocked One-Two punch strategy to boost anti-tumor immunotherapy

Senescent cells are characterized by a persistent cessation of their cell cycle, rendering them valuable targets for anti-tumor strategies in cancer treatment. Numerous studies have explored induced senescence as a promising approach in tumor therapy. Nevertheless, these treatments often come with drawbacks, including adverse side effects and weaker senescence-inducing effects. To address these challenges, we synthesized 223Ra/Ba single-atom nanozyme (SAzyme), wherein Ba SAzyme acts concurrently as a carrier for 223RaCl2, facilitating targeted delivery and minimizing side effects. The 223Ra/Ba SAzyme complex enhances various enzyme-mimicking functions, including catalase (CAT) and peroxidase (POD) activities. Importantly, 223Ra/Ba SAzyme induces cellular senescence and boost anti-tumor immunity. The persistent presence of a senescence-associated secretory phenotype (SASP) in the tumor microenvironment presents risks of immune suppression and tumor recurrence, which can be effectively mitigated by senolytics. As a result, 223Ra/Ba SAzyme were combined with anti-PD-L1 checkpoint blockade to achieve a one-two punch therapy, wherein 223Ra/Ba SAzyme exploits senescence followed by anti-PD-L1 therapy to eradicate senescent cells. This one-two punch strategy approach presents a straightforward and potent intervention for both primary tumors and distant tumor.

Altered X-chromosome inactivation of the TLR7/8 locus and heterogeneity of pDCs in systemic sclerosis

Systemic sclerosis (SSc) is an autoimmune disease that has a strong female predominance. Both the X-linked TLR7 and TLR8 can induce type I IFN (IFN-I) by plasmacytoid DCs (pDCs), which can promote fibrosis. We identified five subclusters of pDCs, including ISGhigh clusters that were over-represented in SSc patients. We observed that both TLR7 and TLR8 genes escape from X chromosome inactivation (XCI) at higher frequency in pDCs of SSc patients, which was associated with changes in TLR7 protein profile. Combined DNA/RNA FISH analysis revealed that the TLR7/8 locus is preferentially located outside of the inactive X (Xi) territory when TLR7 is expressed, suggesting that higher-order loop formation is linked to TLR7/8 expression from the Xi. Furthermore, the expression levels of XIST and the transcriptional repressor SPEN were reduced in SSc pDCs. Hence, our data revealed the heterogeneity of pDCs in SSc and suggested that altered XCI at the TLR7/8 locus may contribute to the chronic IFN-I activity of pDCs in female SSc patients.

Identification of the Polo-like kinase substrate required for homologous synapsis

The synaptonemal complex (SC) is a zipper-like protein structure that aligns homologous chromosome pairs and regulates recombination during meiosis. Despite its conserved appearance and function, how synapsis occurs between chromosome axes remains elusive. Here, we demonstrate that Polo-like kinases (PLKs) phosphorylate a single conserved residue in the disordered C-terminal tails of two paralogous SC subunits, SYP-5 and SYP-6, to establish an electrostatic interface between the SC central region and chromosome axes in C. elegans. While SYP-5/6 phosphorylation is dispensable for the ability of SC proteins to self-assemble, local phosphorylation by PLKs at the pairing center is crucial for SC elongation between homologous chromosome axes. Additionally, SYP-5/6 phosphorylation is essential for asymmetric SC disassembly and proper PLK-2 localization after crossover designation, which drives chromosome remodeling required for homolog separation during meiosis I. This work identifies a key regulatory mechanism by which localized PLK activity mediates the SC-axis interaction through phosphorylation of SYP-5/6, coupling synapsis initiation to homolog pairing.

Somatic polyploidy supports biosynthesis and tissue function by increasing transcriptional output

Cell size and biosynthetic capacity generally increase with increased DNA content. Somatic polyploidy has therefore been proposed to be an adaptive strategy to increase cell size in specialized tissues with high biosynthetic demands. However, if and how DNA concentration limits cellular biosynthesis in vivo is not well understood. Here, we show that polyploidy in the Caenorhabditis elegans intestine is critical for cell growth and yolk biosynthesis, a central role of this organ. Artificially lowering the DNA/cytoplasm ratio by reducing polyploidization in the intestine gave rise to smaller cells with dilute mRNA. Highly expressed transcripts were more sensitive to this mRNA dilution, whereas lowly expressed genes were partially compensated-in part by loading more RNA Polymerase II on the remaining genomes. Polyploidy-deficient animals produced fewer and slower-growing offspring, consistent with reduced synthesis of highly expressed yolk proteins. DNA-dilute cells had normal total protein concentration, which we propose is achieved by increasing the expression of translational machinery at the expense of specialized, cell-type-specific proteins.

Salsolinol as an RNA m6A methylation inducer mediates dopaminergic neuronal death by regulating YAP1 and autophagy

JOURNAL/nrgr/04.03/01300535-202503000-00032/figure1/v/2024-06-17T092413Z/r/image-tiff Salsolinol (1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline, Sal) is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, an environmental toxin that causes Parkinson's disease. However, the mechanism by which Sal mediates dopaminergic neuronal death remains unclear. In this study, we found that Sal significantly enhanced the global level of N6-methyladenosine (m6A) RNA methylation in PC12 cells, mainly by inducing the downregulation of the expression of m6A demethylases fat mass and obesity-associated protein (FTO) and alkB homolog 5 (ALKBH5). RNA sequencing analysis showed that Sal downregulated the Hippo signaling pathway. The m6A reader YTH domain-containing family protein 2 (YTHDF2) promoted the degradation of m6A-containing Yes-associated protein 1 (YAP1) mRNA, which is a downstream key effector in the Hippo signaling pathway. Additionally, downregulation of YAP1 promoted autophagy, indicating that the mutual regulation between YAP1 and autophagy can lead to neurotoxicity. These findings reveal the role of Sal on m6A RNA methylation and suggest that Sal may act as an RNA methylation inducer mediating dopaminergic neuronal death through YAP1 and autophagy. Our results provide greater insights into the neurotoxic effects of catechol isoquinolines compared with other studies and may be a reference for assessing the involvement of RNA methylation in the pathogenesis of Parkinson's disease.

Forced Degradation Study of an Anti-Diabetic Drug Imeglimin: Impurity Profiling and Structure Elucidation Using LC-Q-ToF-MS/MS and NMR

RATIONALE

The present study aims to establish structures of the degradation products of an anti-diabetic drug, Imeglimin (IMG) approved for the treatment of type 2 diabetes mellitus in the year 2021. Degradation pathways are proposed along with in silico toxicity assessments of the observed degradation products (DPs) of the drug.

METHODS

A reversed-phase high-performance liquid chromatography (RP-HPLC), equipped with a photodiode array detector, was used to separate the observed DPs with a Phenomenex Luna PFP (250 × 4.6 mm, 5 μm) column, using 10 mM ammonium formate (pH 4.5) and methanol as mobile phase. Liquid chromatography quadrupole time of flight mass spectrometry (LC-Q-ToF-MS/MS) and nuclear magnetic resonance (NMR) spectroscopy were employed for structural elucidation. Zeneth and Derek suites were used for in silico assessments.

RESULTS

A total of four degradation products were observed, which were successfully separated on an RP-HPLC. The structural characterization of three of the four DPs was achieved using LC-Q-TOF-MS/MS by employing electro spray ionization as well as atmospheric pressure chemical ionization. Additionally, DP-3 was isolated using a preparative HPLC and was characterized by NMR. Computationally predicted structures were compared with the experimental observations.

CONCLUSION

An HPLC method, capable of separating the Imeglimin and its four DPs, was developed and validated as per the ICH Q2(R1) guideline. Structure elucidation reveals a variety of products with metformin as one of the identified DPs along with a metabolite. The toxicity potential of DPs was assessed through docking studies.

Novel determinants of NOTCH1 trafficking and signaling in breast epithelial cells

The evolutionarily conserved Notch signaling pathway controls cell-cell communication, enacting cell fate decisions during development and tissue homeostasis. Its dysregulation is associated with a wide range of diseases, including congenital disorders and cancers. Signaling outputs depend on maturation of Notch receptors and trafficking to the plasma membrane, endocytic uptake and sorting, lysosomal and proteasomal degradation, and ligand-dependent and independent proteolytic cleavages. We devised assays to follow quantitatively the trafficking and signaling of endogenous human NOTCH1 receptor in breast epithelial cells in culture. Based on such analyses, we executed a high-content screen of 2,749 human genes to identify new regulators of Notch that might be amenable to pharmacologic intervention. We uncovered 39 new NOTCH1 modulators for NOTCH1 trafficking and signaling. Among them, we find that PTPN23 and HCN2 act as positive NOTCH1 regulators by promoting endocytic trafficking and NOTCH1 maturation in the Golgi apparatus, respectively, whereas SGK3 serves as a negative regulator that can be modulated by pharmacologic inhibition. Our findings might be relevant in the search of new strategies to counteract pathologic Notch signaling.

The use of a multi-metric readout screen to identify EHMT2/G9a-inhibition as a modulator of cancer-associated fibroblast activation state

Cancer-associated fibroblasts (CAFs) play a pivotal role in cancer progression, including mediating tumour cell invasion via their pro-invasive secretory profile and ability to remodel the extracellular matrix (ECM). Given that reduced CAF abundance in tumours correlates with improved outcomes in various cancers, we set out to identify epigenetic targets involved in CAF activation in regions of tumour-stromal mixing with the goal of reducing tumour aggressiveness. Using the GLAnCE (Gels for Live Analysis of Compartmentalized Environments) platform, we performed an image-based, phenotypic screen that enabled us to identify modulators of CAF abundance and the capacity of CAFs to induce tumour cell invasion. We identified EHMT2 (also known as G9a), an enzyme that targets the methylation of histone 3 lysine 9 (H3K9), as a potent modulator of CAF abundance and CAF-mediated tumour cell invasion. Transcriptomic and functional analysis of EHMT2-inhibited CAFs revealed EHMT2 participated in driving CAFs towards a pro-invasive phenotype and mediated CAF hyperproliferation, a feature typically associated with activated fibroblasts in tumours. Our study suggests that EHMT2 regulates CAF state within the tumour microenvironment by impacting CAF activation, as well as by magnifying the pro-invasive effects of these activated CAFs on tumour cell invasion through promoting CAF hyperproliferation.

Crosstalk between degradation and bioenergetics: how autophagy and endolysosomal processes regulate energy production

Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy production, and metabolic reprogramming stipulates a shift in such balance to optimize both bioenergetic efficiency and anabolic requirements. Failure in switching bioenergetic dependence can lead to maladaptation and pathogenesis. While cellular degradation is known to recycle precursor molecules for anabolism, its potential role in regulating energy production remains less explored. The bioenergetic switch between glycolysis and mitochondrial respiration involves transcription factors and organelle homeostasis, which are both regulated by the cellular degradation pathways. A growing body of studies has demonstrated that both stem cells and differentiated cells exhibit bioenergetic switch upon perturbations of autophagic activity or endolysosomal processes. Here, we highlighted the current understanding of the interplay between degradation processes, specifically autophagy and endolysosomes, transcription factors, endolysosomal signaling, and mitochondrial homeostasis in shaping cellular bioenergetics. This review aims to summarize the relationship between degradation processes and bioenergetics, providing a foundation for future research to unveil deeper mechanistic insights into bioenergetic regulation.

Mesoporous cerium oxide nanoenzyme for Efficacious impeding tumor and metastasis via Conferring resistance to anoikis

Tumor cells can survive when detached from the extracellular matrix or lose cell-to-cell connections, leading to a phenomenon known as anoikis resistance (AR). AR is closely associated with the metastasis and proliferation of tumor cells, enabling them to disseminate, migrate, and invade after detachment. Here, we have investigated a novel composite nanoenzyme comprising mesoporous silica/nano-cerium oxide (MSN-Ce@SP/PEG). This nanoenzyme exhibited satisfactory catalase (CAT) activity, efficiently converting high levels of H2O2 within tumor cells into O2, effectively alleviating tumor hypoxia. Furthermore, MSN-Ce@SP/PEG nanoenzyme demonstrated high peroxidase (POD) activity, elevating reactive oxygen species (ROS) levels and attenuating AR in hepatocellular carcinoma (HCC) cells. The MSN-Ce@SP/PEG nanoenzyme exhibited satisfactory dual bioactivity in CAT and POD and was significantly enhanced under favorable photothermal conditions. Through the synergistic effects of these capabilities, the nanoenzyme disrupted the epithelial-mesenchymal transition (EMT) process in detached HCC cells, ultimately inhibiting the recurrence and metastasis potential of anoikis-resistant HCC cells. This study represents the first report of a novel nanoenzyme based on mesoporous silica/nano-cerium oxide for treating AR in HCC cells, thereby suppressing HCC recurrence and metastasis. The findings of this work offer a pioneering perspective for the development of innovative strategies to prevent the recurrence and metastasis of HCC.

The application and prospects of drug delivery systems in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease primarily affecting elderly individuals aged >65 years and has a poor prognosis. No effective treatment is currently available for IPF. The two antipulmonary fibrosis drugs nintedanib and pirfenidone approved by the FDA in the United States have somewhat decelerated IPF progression. However, the side effects of these drugs can lead to poor patient tolerance and compliance with the medications. Researchers have recently developed various methods for IPF treatment, such as gene silencing and pathway inhibitors, which hold great promise in IPF treatment. Nevertheless, the nonselectivity and nonspecificity of drugs often affect their efficacies. Drug delivery systems (DDS) are crucial for delivering drugs to specific target tissues or cells, thereby minimizing potential side effects, enhancing drug bioavailability, and reducing lung deposition. This review comprehensively summarizes the current state of DDS and various delivery strategies for IPF treatment (e.g., nano-delivery, hydrogel delivery, and biological carrier delivery) to completely expound the delivery mechanisms of different drug delivery carriers. Subsequently, the advantages and disadvantages of different DDS are fully discussed. Finally, the challenges and difficulties associated with the use of different DDS are addressed so as to accelerate their rapid clinical translation.

Research of in vivo reprogramming toward clinical applications in regenerative medicine: A concise review

The successful generation of induced pluripotent stem cells (iPSCs) has significantly impacted many scientific fields. In the field of regenerative medicine, iPSC-derived somatic cells are expected to recover impaired organ functions through cell transplantation therapy. Subsequent studies using genetically engineered mouse models showed that somatic cells are also reprogrammable in vivo. Notably, cyclic expression of reprogramming factors, so-called partial reprogramming in vivo ameliorates cellular and physiological hallmarks of aging without inducing teratoma formation or premature death of animals. Subsequent studies provided evidence supporting the beneficial effects of partial reprogramming in various organs. Although in vivo reprogramming appears to be a promising strategy for tissue regeneration and rejuvenation, there remain unsolved issues that hinder its clinical application, including concerns regarding its safety, controllability, and unexpected detrimental effects. Here, we review the pathway that research of in vivo reprogramming has followed and discuss the future perspective as we look toward its clinical application in regenerative medicine.

Cell calcification reverses the chemoresistance of cancer cells via the conversion of glycolipid metabolism

Drug resistance is an inherent challenge during cancer chemotherapy. Cancer cells favor fatty acid metabolism through metabolic reprogramming to achieve therapeutic resistance. However, an effective approach to overcoming the switch from glycolysis-dependent to fatty acid beta-oxidation-dependent anabolic and energy metabolism remains elusive. Here, we developed a macromolecular drug (folate-polySia, FpSA) to induce the extracellular microcalcification of cervical cancer cells with cisplatin resistance. Microcalcification attenuated the uptake of fatty acids and the beta-oxidation of fatty acids by mitochondrial dysfunction but boosted the glycolysis pathway. Consequently, cotreatment with Pt and FpSA inhibited cisplatin-resistant tumor growth and improved tumor-bearing mice's survival rates, indicating that FpSA switched fatty acid metabolism to glycolysis to sensitize cisplatin-resistant cells further. Taken together, cancer cell calcification induced by FpSA provides a reprogramming metabolic strategy for the treatment of chemotherapy-resistant tumors.

In-Source Collision-Induced Dissociation (CID) Improves Higher-Energy Collisional Dissociation (HCD)-Dependent Fragmentation of ADP-Ribosyl Peptides

RATIONALE

ADP-ribosylation is a posttranslational modification whose higher-energy collisional dissociation (HCD) products are dominated by complete or partial modification losses, complicating peptide sequencing and acceptor site localization efforts. We tested whether in-source collision-induced dissociation (CID) performed on a quadrupole-Orbitrap could convert ADPr to the smaller phosphoribose-H2O derivative to facilitate HCD-dependent peptide sequencing.

METHODS

ADP-ribosyl (ADPr) peptides derived from the human macrophage-like cell line THP-1 were analyzed on a quadrupole-Orbitrap. We monitored the dissociation of ADPr (+ 541.061 Da) to phosphoribosyl-H2O (+ 193.997 Da) peptides while varying the source and high-field asymmetric waveform ion mobility mass spectrometry (FAIMS) compensation voltages. Xcorr and ptmRS were used to evaluate peptide sequencing and acceptor site confidence, respectively. Phosphoribosyl-H2O acceptor sites were compared with those determined by electron-transfer higher-energy collision dissociation (EThcD), performed on a quadrupole-ion trap-Orbitrap.

RESULTS

In-source CID of ADPr peptides to their phosphoribosyl-H2O derivatives increased with increasing source voltage (up to 50 V), as judged by monitoring the corresponding modification loss ([adenosine monophosphate/AMP]+) and the number of identified phosphoribosyl-H2O peptide identifications. The average Xcorr increased from 1.36 (ADPr) to 2.26 (phosphoribosyl-H2O), similar to that achieved with EThcD for ADPr peptides (2.29). The number of high-confidence acceptor sites (> 95%) also increased, from 31% (ADPr) to 70% (phosphoribosyl-H2O), which was comparable to EThcD (70%).

CONCLUSIONS

In-source CID converts ADP-ribosyl to phosphoribosyl-H2O peptides that are more amenable to HCD-dependent peptide sequencing, providing an alternative method for acceptor site determination when ETD-based methods are not available.

Artemisia capillaris Thunb. Water extract alleviates metabolic dysfunction-associated Steatotic liver disease Disease by inhibiting miR-34a-5p to activate Sirt1-mediated hepatic lipid metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Artemisia capillaris Thunb. (ACT) is a plant in the Asteraceae family. Its traditional effects are to clear away dampness and heat, promote gallbladder and reduce jaundice. Traditional Chinese medicine believes that MASLD is a damp-heat syndrome. The group's previous study showed that Artemisia capillaris Thunb. Water Extract (ACTE) has an improved effect on MASLD.

AIM OF THE STUDY AND METHODS

In order to further understand its mechanism of action, this study established a mouse MASLD model and a HepG2 cell lipid droplet model, combined small RNA sequencing and miRNA transfection experiments, to explore the mechanism of ACTE to improve MASLD by modulating miRNA-targeted mRNA. Non-targeted metabolomics method was used to detect and analyze ACTE.

RESULTS

This study screened miR-34a-5p and confirmed its target mRNA-Sirtuin 1 (Sirt1). MASLD induced high expression of miR-34a-5p and low expression of Sirt1, and ACE reversed these changes. When overexpressing miR-34a-5p or knocking down Sirt1, the effect of ACE in reducing PO (palmitic acid and oleic acid complex)-induced lipid accumulation in HepG2 cells was attenuated. ACTE reduces the expression of FASN, SCD1, ACC, and SREBP-1c, promotes the expression of CPT-1 and HSL, thereby reducing lipid accumulation.

CONCLUSIONS

ACTE activates Sirt1 by inhibiting the expression of miR-34a-5p, thereby reducing liver lipid accumulation and improving HFD-induced MASLD. These findings highlight the potential of ACTE in reducing weight, controlling obesity, and improving lipid metabolism disorders.

MCM10: A potential biomarker for cervical cancer and precancerous lesions

Cervical cancer remains a significant health burden worldwide, emphasizing the need for early detection and intervention. DNA replication is perturbed in cancer cells, and the minichromosome maintenance protein 10 plays an important role in origin firing. By analyzing the MCM10 mRNA expression in healthy controls, precancerous lesions, and cervical cancer using qRT-PCR, we can infer if it can be considered a biomarker. We collected cervical smear samples from patients and performed MCM10 expression analysis to set up thresholds for risk stratification. We also investigated the HPV status among the patient samples with precancerous lesions and cervical cancer and found 70 % of them to be positive. Our results demonstrated a significant upregulation of MCM10 mRNA expression in tumor samples (n = 40, 7.83 ± 1.2) and precancerous lesions (n = 54, 5.69 ± 1.4) compared to normal (n = 50, 4.27 ± 0.80) with a R2 value of 0.59, confirming its role in the progression and development of cervical cancer. In conclusion, this study emphasizes the potential role of MCM10 as a biomarker. Our study would improve early detection rates, and we propose MCM10-based community screening for risk stratification, prevention, and prognosis.

N6-methyladenosine in inflammatory diseases: Important actors and regulatory targets

N6-methyladenosine (m6A) is one of the most prevalent epigenetic modifications in eukaryotic cells. It regulates RNA function and stability by modifying RNA methylation through writers, erasers, and readers. As a result, m6A plays a critical role in a wide range of biological processes. Inflammation is a common and fundamental pathological process. Numerous studies have investigated the role of m6A modifications in inflammatory diseases. This review highlights the mechanisms by which m6A contributes to inflammation, focusing on pathogen-induced infectious diseases, autoimmune disorders, allergic conditions, and metabolic disorder-related inflammatory diseases.

Transcriptional dynamics and tissue-specific expression patterns of transposable elements in orthopteran insects

Transposable elements (TEs) are prevalent in the genomes of orthopteran insects, contributing significantly to their genome evolution and diversity. In light of the existing gap in our understanding of TEs transcript dynamics in orthopteran insects, we recognize the critical need to undertake comprehensive analyses in this area. Therefore, we have decided to delve into the characterization of TE transcripts, their abundance profiles, and the formation of chimeric transcripts using RNA-seq data and genome assemblies. The transcript analysis of TEs across various species revealed significant differences in TE abundance and expression patterns. In particular, Schistocerca americana exhibited twice the number of transcripts within the genus Schistocerca compared to the average of other species, while Gryllus bimaculatus displayed the lowest number of transcripts. Despite this, all Schistocerca species shared similar fractions of TE transcripts at the clade level, with DNA transposons (45%) being the most abundant, followed by LINE (19%) and LTR elements (18%). Interestingly, Acrida cinerea displayed different TE abundance patterns compared to Schistocerca species, particularly with an increased proportion of LTR transcripts, accounting for 31% of the total transcripts. Further analysis revealed tissue-specific transcriptional activity of TE clades, with notable differences between male and female specimens. In Gryllus bimaculatus, TEs were highly transcribed across ovaries and gut tissues in females compared to male testes and gut. Conversely, Gastrimargus marmoratus displayed higher TE transcription in male tissues compared to females, indicating species-specific expression patterns. A similar pattern has been observed in Acrida cinerea, except in female gonads, where 4618 TEs were transcribed compared to 3757 in male gonads. Despite these variations, no correlation was found between genome size and TE transcript abundance. Additionally, highly conserved TEs were involved in the formation of chimeric transcripts, indicating potential regulatory roles in gene expression. The expression quantification analysis of chimeric TEs and genes revealed tissue-specific expression patterns, and TEs do not control the overall expression of all genes except some, suggesting regulatory roles of TEs in gene expression. Overall, our study underscores tissue-specific variations in TE expression and transcript abundance among different species. Additionally, our findings suggest the involvement of highly conserved TEs in the formation of chimeric transcripts across different species.

The kinetochore protein KNL-1 regulates the actin cytoskeleton to control dendrite branching

The function of the nervous system is intimately tied to its complex and highly interconnected architecture. Precise control of dendritic branching in individual neurons is central to building the complex structure of the nervous system. Here, we show that the kinetochore protein KNL-1 and its associated KMN (Knl1/Mis12/Ndc80 complex) network partners, typically known for their role in chromosome-microtubule coupling during mitosis, control dendrite branching in the Caenorhabditis elegans mechanosensory PVD neuron. KNL-1 restrains excess dendritic branching and promotes contact-dependent repulsion events, ensuring robust sensory behavior and preventing premature neurodegeneration. Unexpectedly, KNL-1 loss resulted in significant alterations of the actin cytoskeleton alongside changes in microtubule dynamics within dendrites. We show that KNL-1 modulates F-actin dynamics to generate proper dendrite architecture and that its N-terminus can initiate F-actin assembly. These findings reveal that the postmitotic neuronal KMN network acts to shape the developing nervous system by regulating the actin cytoskeleton and provide new insight into the mechanisms controlling dendrite architecture.

Real-time imaging reveals a role for macrophage protrusive motility in melanoma invasion

Macrophages are primary cells of the innate immune system that mediate tumor progression. However, the motile behavior of macrophages and interactions with tumor cells are not well understood. Here, we exploit the optical transparency of larval zebrafish and perform real-time imaging of macrophage-melanoma interactions. We found that macrophages are highly motile in the tumor microenvironment. Macrophages extend dynamic projections between tumor cells that precede invasive melanoma migration. Modulating macrophage motility with a dominant inhibitory mutation in Rac2 inhibits recruitment to the tumor and impairs tumor invasion. However, a hyperactivating mutation in Rac2 does not affect macrophage recruitment but limits macrophage projections into the melanoma mass and reduces invasive melanoma cell migration. Taken together, these findings reveal a role for Rac2-mediated macrophage protrusive motility in melanoma invasion.

Securin regulates the spatiotemporal dynamics of separase

Separase regulates multiple aspects of the metaphase-to-anaphase transition. Separase cleaves cohesin to allow chromosome segregation and localizes to vesicles to promote exocytosis. The anaphase-promoting complex/cyclosome (APC/C) activates separase by ubiquitinating its inhibitory chaperone, securin, triggering its degradation. How this pathway controls the exocytic function of separase is unknown. During meiosis I, securin is degraded over several minutes, while separase rapidly relocalizes from kinetochore structures at the spindle and cortex to sites of action on chromosomes and vesicles at anaphase onset. The loss of cohesin coincides with the relocalization of separase to the chromosome midbivalent at anaphase onset. APC/C depletion prevents separase relocalization, while securin depletion causes precocious separase relocalization. Expression of non-degradable securin inhibits chromosome segregation, exocytosis, and separase localization to vesicles but not to the anaphase spindle. We conclude that APC/C-mediated securin degradation controls separase localization. This spatiotemporal regulation will impact the effective local concentration of separase for more precise targeting of substrates in anaphase.

A function of TPL/TBL1-type corepressors is to nucleate the assembly of the preinitiation complex

The plant corepressor TPL is recruited to diverse chromatin contexts, yet its mechanism of repression remains unclear. Previously, we leveraged the fact that TPL retains its function in a synthetic transcriptional circuit in the yeast model Saccharomyces cerevisiae to localize repressive function to two distinct domains. Here, we employed two unbiased whole-genome approaches to map the physical and genetic interactions of TPL at a repressed locus. We identified SPT4, SPT5, and SPT6 as necessary for repression with SPT4 acting as a bridge connecting TPL to SPT5 and SPT6. We discovered the association of multiple additional constituents of the transcriptional preinitiation complex at TPL-repressed promoters, specifically those involved early in transcription initiation. These findings were validated in yeast and plants, including a novel method to analyze the conditional loss of function of essential genes in plants. Our findings support a model where TPL nucleates preassembly of the transcription activation machinery to facilitate the rapid onset of transcription once repression is relieved.

Genome-wide conditional degron libraries for functional genomics

Functional genomics with libraries of knockout alleles is limited to non-essential genes and convoluted by the potential accumulation of suppressor mutations in knockout backgrounds, which can lead to erroneous functional annotations. To address these limitations, we constructed genome-wide libraries of conditional alleles based on the auxin-inducible degron (AID) system for inducible degradation of AID-tagged proteins in the budding yeast Saccharomyces cerevisiae. First, we determined that N-terminal tagging is at least twice as likely to inadvertently impair protein function across the proteome. We thus constructed two libraries with over 5,600 essential and non-essential proteins fused at the C-terminus with an AID tag and an optional fluorescent protein. Approximately 90% of AID-tagged proteins were degraded in the presence of the auxin analog 5-Ph-IAA, with initial protein abundance and tag accessibility as limiting factors. Genome-wide screens for DNA damage response factors revealed a role for the glucose signaling factor GSF2 in resistance to hydroxyurea, highlighting how the AID libraries extend the yeast genetics toolbox.

Identification of coilin interactors reveals coordinated control of Cajal body number and structure

The cell nucleus contains distinct biomolecular condensates that form at specific genetic loci, organize chromosomes in 3D space, and regulate RNA processing. Among these, Cajal bodies (CBs) require key "scaffolding" proteins for their assembly, which is not fully understood. Here, we employ proximity biotinylation, mass spectrometry, and functional screening to comprehensively identify and test the functions of CB components. We document 144 protein interactors of coilin, of which 70 were newly detected, and establish 25 players needed for CB assembly and/or maintenance. Surprisingly, the depletion of nine coilin interactors-mostly constituents of the 60S ribosome (RPLs)-increased CB number and caused subdomains defined by coilin and the survival motor neuron protein (SMN) to merge. These phenotypes were traceable to altered nuclear levels of dimethylarginine. Our data implicate RPL24 and other players in the regulation of CBs by modulating posttranslational modifications. Moreover, the prevalence of transcription factors among the identified components highlights roles for gene activity in CB assembly and nuclear positioning.

Insect olfactory neurons: receptors, development, and function

Insects represent the most diverse group of animals in the world. While the olfactory systems of different species share general principles of organization, they also exhibit a wide range of structural and functional diversity. Scientists have gained tremendous insight into olfactory neural development and function, notably in Drosophila, but also in other insect species (see reviews by Benton, 2022; Robertson, 2019; Yan et al., 2020). In the last few years, new evidence has steadily mounted, for example, the stoichiometry of odorant receptor and co-receptor (OR-Orco) complex. This review aims to highlight the recent progress on four aspects: (1) the structure and function of the OR-Orco complex, (2) chemosensory gene co-expression, (3) diverse neural developmental processes, and (4) the role of genes and neurons in olfactory development and olfactory-mediated behavior.

Plant YABBY transcription factors: a review of gene expression, biological functions, and prospects

Transcription factors often contain several different functional regions, including DNA-binding domains, and play an important regulatory role in plant growth, development, and the response to external stimuli. YABYY transcription factors are plant-specific and contain two special domains (N-terminal C2C2 zinc-finger and C-terminal helix-loop-helix domains) that are indispensable. Specifically, YABBY transcription factors play key roles in maintaining the polarity of the adaxial-abaxial axis of leaves, as well as in regulating: vegetative and reproductive growth, hormone response, stress resistance, and secondary metabolite synthesis in plants. Recently, the identification and functional verification of YABBY transcription factors in different plants has increased. On this basis, we summarize recent advances in the: identification, classification, expression patterns, and functions of the YABBY transcription factor family. The normal expression and function of YABBY transcription factors rely on a regulatory network that is established through the interaction of YABBY family members with other genes. We discuss the interaction network of YABBY transcription factors during leaf polarity establishment and floral organ development. This article provides a reference for research on YABBY function, plant genetic improvement, and molecular breeding.

The genomic landscape of short tandem repeats in cattle

Short tandem repeats (STRs) are abundant and have high mutation rates across cattle genomes; however, comprehensive exploration of cattle STRs is needed. Here, we constructed a comprehensive map of 467 553 polymorphic STRs (pSTRs) constructed from 423 cattle genomes representing 59 breeds worldwide. We observed that pSTRs in coding sequences and 5'UTRs (Untranslated Regions) were under strong selective constraints and exhibited a relatively low level of diversity. Furthermore, we found that these pSTRs underwent more contraction than expansion. Population analysis showed a strong positive correlation (R = 1) between pSTR diversity and single nucleotide polymorphic heterozygosity. We also investigated STR differences between taurine and indicine cattle and detected 2301 highly divergent STRs, which might relate to immune, endocrine and neurodevelopmental pathways. In summary, our large-scale study characterizes the spectrum of STRs in cattle, expands the scale of known cattle STR variation and provides novel insights into differences among various cattle subspecies.

Local delivery of platelet-derived factors mitigates ischemia and preserves ovarian function through angiogenic modulation: A personalized regenerative strategy for fertility preservation

As the most prominent and ideal modality in female fertility preservation, ovarian tissue cryopreservation, and transplantation often confront the challenge of ischemic damage and follicular loss from avascular transplantation. To surmount this impediment, we engineered a novel platelet-derived factors-encapsulated fibrin hydrogel (PFH), a paradigmatic biomaterial. PFH encapsulates autologous platelet-derived factors, utilizing the physiological blood coagulation cascade for precise local delivery of bioactive molecules. In our study, PFH markedly bolstered the success of avascular ovarian tissue transplantation. Notably, the quantity and quality of follicles were preserved with improved neovascularization, accompanied by decreased DNA damage, increased ovulation, and superior embryonic development rates under a Low-concentration Platelet-rich plasma-derived factors encapsulated fibrin hydrogel (L-PFH) regimen. At a stabilized point of tissue engraftment, gene expression analysis mirrored normal ovarian tissue profiles, underscoring the effectiveness of L-PFH in mitigating the initial ischemic insult. This autologous blood-derived biomaterial, inspired by nature, capitalizes on the blood coagulation cascade, and combines biodegradability, biocompatibility, safety, and cost-effectiveness. The adjustable properties of this biomaterial, even in injectable form, extend its potential applications into the broader realm of personalized regenerative medicine. PFH emerges as a promising strategy to counter ischemic damage in tissue transplantation, signifying a broader therapeutic prospect. (197 words).

Computing hematopoiesis plasticity in response to genetic mutations and environmental stimulations

Cell plasticity (CP), describing a dynamic cell state, plays a crucial role in maintaining homeostasis during organ morphogenesis, regeneration, and trauma-to-repair biological process. Single-cell-omics datasets provide an unprecedented resource to empower CP analysis. Hematopoiesis offers fertile opportunities to develop quantitative methods for understanding CP. In this study, we generated high-quality lineage-negative single-cell RNA-sequencing datasets under various conditions and introduced a working pipeline named scPlasticity to interrogate naïve and disturbed plasticity of hematopoietic stem and progenitor cells with mutational or environmental challenges. Using embedding methods UMAP or FA, a continuum of hematopoietic development is visually observed in wild type where the pipeline confirms a low proportion of hybrid cells ( P hc , with bias range: 0.4∼0.6) on a transition trajectory. Upon Tet2 mutation, a driver of leukemia, or treatment of DSS, an inducer of colitis, P hc is increased and plasticity of hematopoietic stem and progenitor cells was enhanced. We prioritized several transcription factors and signaling pathways, which are responsible for P hc alterations. In silico perturbation suggests knocking out EGR regulons or pathways of IL-1R1 and β-adrenoreceptor partially reverses P hc promoted by Tet2 mutation and inflammation.

Significant roles of RNA 5-methylcytosine methylation in cancer

Cancer stands as a leading cause of mortality and poses an escalating threat to global health. Epigenetic dysregulation is pivotal in the onset and advancement of cancer. Recent research on RNA 5-methylcytosine (m5C) methylation has underscored its significant role in cancer. RNA m5C methylation is a key component in gene expression regulation and is intricately linked to cancer development, offering valuable insights for cancer diagnosis, treatment, and prognosis. This review provides an in-depth examination of the three types of regulators associated with RNA m5C methylation and their biological functions. It further investigates the expression and impact of RNA m5C methylation and its regulators in cancer, focusing on their mechanisms in cancer progression and clinical relevance. The current research on inhibitors targeting RNA m5C methylation-related regulators remains underdeveloped, necessitating further exploration and discovery.

Transcription factors and hormone receptors: Sex‑specific targets for cancer therapy (Review)

Despite advancements in diagnostic and therapeutic technologies, cancer continues to pose a challenge to disease-free longevity in humans. Numerous factors contribute to the onset and progression of cancer, among which sex differences, as an intrinsic biological condition, warrant further attention. The present review summarizes the roles of hormone receptors estrogen receptor α (ERα), estrogen receptor β (ERβ) and androgen receptor (AR) in seven types of cancer: Breast, prostate, ovarian, lung, gastric, colon and liver cancer. Key cancer-related transcription factors known to be activated through interactions with these hormone receptors have also been discussed. To assess the impact of sex hormone receptors on different cancer types, hormone-related transcription factors were analyzed using the SignaLink 3.0 database. Further analysis focused on six key transcription factors: CCCTC-binding factor, forkhead box A1, retinoic acid receptor α, PBX homeobox 1, GATA binding protein 2 and CDK inhibitor 1A. The present review demonstrates that these transcription factors significantly influence hormone receptor activity across various types of cancer, and elucidates the complex interactions between these transcription factors and hormone receptors, offering new insights into their roles in cancer progression. The findings suggest that targeting these common transcription factors could improve the efficacy of hormone therapy and provide a unified approach to treating various types of cancer. Understanding the dual and context-dependent roles of these transcription factors deepens the current understanding of the molecular mechanisms underlying hormone-driven tumor progression and could lead to more effective targeted therapeutic strategies.

Endo-bind-n-seq: identifying RNA motifs of RNA binding proteins isolated from endogenous sources

RNA binding proteins (RBPs) are crucial regulators of gene expression and critically depend on the specific recognition of their target RNAs. Accordingly, a selection of methods to analyze RBP specificities has been developed, including protein-RNA crosslinking and sequencing (CLIP) and in vitro selection methods such as SELEX, RNA compete or RNA bind-n-seq. However, limitations like the availability for purified recombinant proteins and custom microarray platforms (RNAcompete) or extensive sequencing depth and sophisticated bioinformatic data processing (CLIP) may limit a broader implementation of these methods. Here, we present an RNA bind-n-seq method that uses short random RNA pools and enables multiple rounds of selection. This results in strong motif enrichment with low positional variance thus reducing sequencing depth requirements. Furthermore, we have coupled our protocol to immunoprecipitation of tagged or endogenous RBPs from cultured cells or tissue samples, eliminating the need for recombinant proteins. Our method also allows for the identification of indirect RNA motifs of proteins that are integral parts of multiprotein RNPs and result in physically more relevant RNA motifs.

Ferroptosis and cognitive impairment: Unraveling the link and potential therapeutic targets

Neurodegenerative disorders, such as Alzheimer's and Parkinson's diseases, share key characteristics, notably cognitive impairment and significant cell death in specific brain regions. Cognition, a complex mental process allowing individuals to perceive time and place, is disrupted in these conditions. This consistent disruption suggests the possibility of a shared underlying mechanism across all neurodegenerative diseases. One potential common factor is the activation of pathways leading to cell death. Despite significant progress in understanding cell death pathways, no definitive treatments have emerged. This has shifted focus towards less-explored mechanisms like ferroptosis, which holds potential due to its involvement in oxidative stress and iron metabolism. Unlike apoptosis or necrosis, ferroptosis offers a novel therapeutic avenue due to its distinct biochemical and genetic underpinnings, making it a promising target in neurodegenerative disease treatment. Ferroptosis is distinguished from other cellular death mechanisms, by distinctive characteristics such as an imbalance of iron hemostasis, peroxidation of lipids in the plasma membrane, and dysregulated glutathione metabolism. In this review, we discuss the potential role of ferroptosis in cognitive impairment. We then summarize the evidence linking ferroptosis biomarkers to cognitive impairment brought on by neurodegeneration while highlighting recent advancements in our understanding of the molecular and genetic mechanisms behind the condition. Finally, we discuss the prospective therapeutic implications of targeting ferroptosis for the treatment of cognitive abnormalities associated with neurodegeneration, including natural and synthetic substances that suppress ferroptosis via a variety of mechanisms. Promising therapeutic candidates, including antioxidants and iron chelators, are being explored to inhibit ferroptosis and mitigate cognitive decline.