Decoding chromatin states by proteomic profiling of nucleosome readers.

DNA and histone modifications combine into characteristic patterns that demarcate functional regions of the genome1,2. While many 'readers' of individual modifications have been described3-5, how chromatin states comprising composite modification signatures, histone variants and internucleosomal linker DNA are interpreted is a major open question. Here we use a multidimensional proteomics strategy to systematically examine the interaction of around 2,000 nuclear proteins with over 80 modified dinucleosomes representing promoter, enhancer and heterochromatin states. By deconvoluting complex nucleosome-binding profiles into networks of co-regulated proteins and distinct nucleosomal features driving protein recruitment or exclusion, we show comprehensively how chromatin states are decoded by chromatin readers. We find highly distinctive binding responses to different features, many factors that recognize multiple features, and that nucleosomal modifications and linker DNA operate largely independently in regulating protein binding to chromatin. Our online resource, the Modification Atlas of Regulation by Chromatin States (MARCS), provides in-depth analysis tools to engage with our results and advance the discovery of fundamental principles of genome regulation by chromatin states.

Emerging toolkits for decoding the co-occurrence of modified histones and chromatin proteins.

In eukaryotes, DNA is packaged into chromatin with the help of highly conserved histone proteins. Together with DNA-binding proteins, posttranslational modifications (PTMs) on these histones play crucial roles in regulating genome function, cell fate determination, inheritance of acquired traits, cellular states, and diseases. While most studies have focused on individual DNA-binding proteins, chromatin proteins, or histone PTMs in bulk cell populations, such chromatin features co-occur and potentially act cooperatively to accomplish specific functions in a given cell. This review discusses state-of-the-art techniques for the simultaneous profiling of multiple chromatin features in low-input samples and single cells, focusing on histone PTMs, DNA-binding, and chromatin proteins. We cover the origins of the currently available toolkits, compare and contrast their characteristic features, and discuss challenges and perspectives for future applications. Studying the co-occurrence of histone PTMs, DNA-binding proteins, and chromatin proteins in single cells will be central for a better understanding of the biological relevance of combinatorial chromatin features, their impact on genomic output, and cellular heterogeneity.

Engineering 2D Material Exciton Line Shape with Graphene/h-BN Encapsulation.

Control over the optical properties of atomically thin two-dimensional (2D) layers, including those of transition metal dichalcogenides (TMDs), is needed for future optoelectronic applications. Here, the near-field coupling between TMDs and graphene/graphite is used to engineer the exciton line shape and charge state. Fano-like asymmetric spectral features are produced in WS2, MoSe2, and WSe2 van der Waals heterostructures combined with graphene, graphite, or jointly with hexagonal boron nitride (h-BN) as supporting or encapsulating layers. Furthermore, trion emission is suppressed in h-BN encapsulated WSe2/graphene with a neutral exciton red shift (44 meV) and binding energy reduction (30 meV). The response of these systems to electron beam and light probes is well-described in terms of 2D optical conductivities of the involved materials. Beyond fundamental insights into the interaction of TMD excitons with structured environments, this study opens an unexplored avenue toward shaping the spectral profile of narrow optical modes for application in nanophotonic devices.

Native ChIP: Studying the Genome-Wide Distribution of Histone Modifications in Cells and Tissue.

For the genome-wide mapping of histone modifications, chromatin immunoprecipitation (ChIP) followed by high-throughput sequencing remains the benchmark method. While crosslinked ChIP can be used for all kinds of targets, native ChIP is predominantly used for strong and direct DNA interactors like histones and their modifications. Here we describe a native ChIP protocol that can be used for cells and tissue material.

Non-canonical mRNA translation initiation in cell stress and cancer.

The now well described canonical mRNA translation initiation mechanism of m7G 'cap' recognition by cap-binding protein eIF4E and assembly of the canonical pre-initiation complex consisting of scaffolding protein eIF4G and RNA helicase eIF4A has historically been thought to describe all cellular mRNA translation. However, the past decade has seen the discovery of alternative mechanisms to canonical eIF4E mediated mRNA translation initiation. Studies have shown that non-canonical alternate mechanisms of cellular mRNA translation initiation, whether cap-dependent or independent, serve to provide selective translation of mRNAs under cell physiological and pathological stress conditions. These conditions typically involve the global downregulation of canonical eIF4E1/cap-mediated mRNA translation, and selective translational reprogramming of the cell proteome, as occurs in tumor development and malignant progression. Cancer cells must be able to maintain physiological plasticity to acquire a migratory phenotype, invade tissues, metastasize, survive and adapt to severe microenvironmental stress conditions that involve inhibition of canonical mRNA translation initiation. In this review we describe the emerging, important role of non-canonical, alternate mechanisms of mRNA translation initiation in cancer, particularly in adaptation to stresses and the phenotypic cell fate changes involved in malignant progression and metastasis. These alternate translation initiation mechanisms provide new targets for oncology therapeutics development.

Peace through health: traditional medicine meditation in the prevention of collective stress, violence, and war.

In the midst of global armed conflicts, notably the Israel-Hamas and Ukraine-Russia wars, there is an urgent need for innovative public health strategies in peacebuilding. The devastating impact of wars, including mortality, injury, disease, and the diversion of healthcare resources, necessitates effective and durable interventions. This perspective aligns with WHO recommendations and examines the role of evidence-based meditation from Ayurveda and Yoga in public health to mitigate collective stress and prevent collective violence and war. It highlights the Transcendental Meditation program, recognized for reducing stress, with contemporary evidence supporting its effectiveness in mental health, mind-body disorders, cardiovascular disease, and public health. Empirical studies with cross-cultural replications indicate that these Traditional Medicine meditation practices can reduce collective stress and prevent collective violence and war activity while improving quality of life. The mechanisms of group meditation in mitigating collective violence are explored through public health models, cognitive neuroscience, population neuroscience, quantum physics principles, and systems medicine. This perspective suggests that Transcendental Meditation and the advanced TM-Sidhi program, as a component of Traditional Medicine, can provide a valuable platform for enhancing societal well-being and peace by addressing brain-based factors fundamental to collective stress and violence.

Structural basis of tRNA recognition by the m3C RNA methyltransferase METTL6 in complex with SerRS seryl-tRNA synthetase.

Methylation of cytosine 32 in the anticodon loop of tRNAs to 3-methylcytosine (m3C) is crucial for cellular translation fidelity. Misregulation of the RNA methyltransferases setting this modification can cause aggressive cancers and metabolic disturbances. Here, we report the cryo-electron microscopy structure of the human m3C tRNA methyltransferase METTL6 in complex with seryl-tRNA synthetase (SerRS) and their common substrate tRNASer. Through the complex structure, we identify the tRNA-binding domain of METTL6. We show that SerRS acts as the tRNASer substrate selection factor for METTL6. We demonstrate that SerRS augments the methylation activity of METTL6 and that direct contacts between METTL6 and SerRS are necessary for efficient tRNASer methylation. Finally, on the basis of the structure of METTL6 in complex with SerRS and tRNASer, we postulate a universal tRNA-binding mode for m3C RNA methyltransferases, including METTL2 and METTL8, suggesting that these mammalian paralogs use similar ways to engage their respective tRNA substrates and cofactors.

The promising role of Transcendental Meditation in the prevention and treatment of cardiometabolic diseases: A systematic review.

Psychological distress has a demonstrable impact on cardiovascular diseases (CVD) and risk factors. Transcendental Meditation (TM) has been shown to reduce stress and improve health and well-being. The current review aimed to synthesize the evidence on the effects of TM on cardiometabolic outcomes and identify gaps for future research. We searched PubMed/MEDLINE, EMBASE, SCOPUS, and Web of Science databases for relevant literature. Forty-five papers that reported studies of TM on cardiometabolic risk factors and diseases were included. Evidence shows that TM is effective in reducing blood pressure (BP). We found some evidence that TM can improve insulin resistance and may play a role in improving dyslipidemia, exercise tolerance, and myocardial blood flow, and in reducing carotid intima-media thickness and left ventricular mass. Studies show that long-term TM practice can reduce the risk of myocardial infarction, stroke, and CVD mortality. This review identified that certain studies have high participant drop-out rates, and fewer studies targeted comprehensive cardiometabolic outcomes beyond BP with longer follow-up periods. We found that most studies were conducted in specific populations, which may limit generalizability. In conclusion, TM has the potential to improve cardiometabolic health; however, research gaps highlight the need for larger phase III multicenter clinical trials with long-term follow-ups.

Novel inhibition of central carbon metabolism pathways by Rac and Cdc42 inhibitor MBQ-167 and paclitaxel.

Triple negative breast cancer (TNBC) represents a therapeutic challenge where standard chemotherapy is limited to paclitaxel. MBQ-167, a clinical stage small molecule inhibitor that targets Rac and Cdc42, inhibits tumor growth and metastasis in mouse models of TNBC. Herein, we investigated the efficacy of MBQ-167 in combination with paclitaxel in TNBC pre-clinical models, as a prelude to safety trials of this combination in advanced breast cancer patients. Individual MBQ-167 or combination therapy with paclitaxel was more effective at reducing TNBC cell viability and increasing apoptosis compared to paclitaxel alone. In orthotopic mouse models of human TNBC (MDA-MB-231 and MDA-MB-468), individual MBQ-167, paclitaxel, or the combination reduced mammary tumor growth with similar efficacy, with no apparent liver toxicity. However, paclitaxel single agent treatment significantly increased lung metastasis, while MBQ-167, single or combined, reduced lung metastasis. In the syngeneic 4T1/BALB/c model, combined MBQ-167 and paclitaxel decreased established lung metastases by ~80%. To determine the molecular basis for the improved efficacy of the combined treatment on metastasis, 4T1 tumor extracts from BALB/c mice treated with MBQ-167, paclitaxel, or the combination were subjected to transcriptomic analysis. Gene set enrichment identified specific downregulation of central carbon metabolic pathways by the combination of MBQ-167 and Paclitaxel but not individual compounds. Biochemical validation, by immunoblotting and metabolic Seahorse analysis, shows that combined MBQ-167 and paclitaxel reduces glycolysis. This study provides a strong rationale for the clinical testing of MBQ-167 in combination with paclitaxel as a potential therapeutic for TNBC and identifies a unique mechanism of action.

Engineered coiled-coil HIF1α protein domain mimic.

The development of targeted anti-cancer therapeutics offers the potential for increased efficacy of drugs and diagnostics. Utilizing modalities agnostic to tumor type, such as the hypoxic tumor microenvironment (TME), may assist in the development of universal tumor targeting agents. The hypoxia-inducible factor (HIF), in particular HIF1, plays a key role in tumor adaptation to hypoxia, and inhibiting its interaction with p300 has been shown to provide therapeutic potential. Using a multivalent assembled protein (MAP) approach based on the self-assembly of the cartilage oligomeric matrix protein coiled-coil (COMPcc) domain fused to the critical residues of the C-terminal transactivation domain (C-TAD) of the α subunit of HIF1 (HIF1α), we generate HIF1α-MAP (H-MAP). The resulting H-MAP demonstrates picomolar binding affinity to p300, the ability to downregulate hypoxia-inducible genes, and in vivo tumor targeting capability.

Coiled-Coil Protein Hydrogels Engineered with Minimized Fiber Diameters for Sustained Release of Doxorubicin in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) lacks expressed protein targets, making therapy development challenging. Hydrogels offer a promising new route in this regard by improving the chemotherapeutic efficacy through increased solubility and sustained release. Moreover, subcutaneous hydrogel administration reduces patient burden by requiring less therapy and shorter treatment times. We recently established the design principles for the supramolecular assembly of single-domain coiled-coils into hydrogels. Using a modified computational design algorithm, we designed Q8, a hydrogel with rapid assembly for faster therapeutic hydrogel preparation. Q8 encapsulates and releases doxorubicin (Dox), enabling localized sustained release via subcutaneous injection. Remarkably, a single subcutaneous injection of Dox-laden Q8 (Q8•Dox) significantly suppresses tumors within just 1 week. This work showcases the bottom-up engineering of a fully protein-based drug delivery vehicle for improved TBNC treatment via noninvasive localized therapy.

Case report: Robotically visualized and biopsy-confirmed peritoneal carcinomatosis as initial identification of metastatic prostate adenocarcinoma in a patient with a history of prostatic urethral lift.

Background: Peritoneal carcinomatosis is a particularly rare presentation of prostate cancer. Here we report a rare clinical case of surgically identified peritoneal carcinomatosis at the time of a planned robotic prostatectomy in a patient with a history of prostatic urethral lift procedure. Case presentation: A 72-year-old man, with a history of urinary retention managed with tamsulosin, presented to his local urologist. Prostatic urethral lift procedures were performed for symptom management. After a definitive uptrend in his prostate-specific antigen (PSA) values, a biopsy was obtained, which demonstrated prostate adenocarcinoma. On presurgical multidisciplinary review, it was presumed that he had very high-risk localized prostate cancer. However, upon initiation of robotically assisted laparoscopic radical prostatectomy (RALP), he was noted to have numerous punctate white plaques on the peritoneum; biopsy of these lesions confirmed metastatic disease-for which the patient was starting on triple therapy per the PEACE-1 trial. The PSA level responded appropriately, decreasing from 16.8 to 0.08. Genetic testing was performed and returned negative for any clinically significant mutations. Conclusion: Our patient, diagnosed with peritoneal carcinomatosis during a planned RALP, highlights the importance of vigilant laparoscopic exam prior to this prostatectomy. Multidisciplinary discussion is crucial for individualized and optimal treatment planning.