FEBS Letters最新文献

Cutaneous leishmaniasis (CL) presents diverse clinical challenges due to species-specific drug efficacy and resistance. We propose a novel therapeutic strategy using synthetic biology to reprogram macrophage responses. By engineering an inducible TET-ON gene circuit to express immunomodulatory PeptideA (PepA), we enhance IL-12 production and parasite clearance. Peptides were identified via AI and validated through molecular dynamics simulations. This approach shifts macrophages toward a pro-inflammatory M1 phenotype, improving infection outcomes. Delivery via Tac-6 nanogel and adoptive transfer enables in vivo expression. Our method offers targeted, controllable treatment for CL, potentially overcoming current limitations. This platform also provides a versatile pipeline for studying macrophage-associated infections and inflammatory diseases, paving the way for precision immunotherapy. Impact statement We present a synthetic biology-based approach to treat cutaneous leishmaniasis by reprogramming macrophages with an inducible gene circuit expressing AI-designed peptides that boost IL-12 production and parasite clearance. Delivered via Tac-6 nanogel, this strategy offers targeted, resistance-mitigating therapy and a versatile platform for macrophage-driven diseases.

The brain vasculature is a critical barrier to maintain central nervous system (CNS) homeostasis. Parasitic infections can profoundly disrupt the brain vasculature, with consequences ranging from subtle neurological alterations to severe, life-threatening pathologies. In this review, we explore the diverse mechanisms by which endoparasites interact with, modulate and breach CNS blood and lymphatic vessels. We highlight how these pathogens manipulate endothelial function, alter barrier permeability and exploit vascular surface molecules to access or influence the brain. These interactions often trigger local inflammation, endothelial activation and blood-brain barrier breakdown, with significant implications for parasite survival and host pathology. Here, we review the molecular and cellular mechanisms underlying these processes, providing an integrative view of parasite-vascular crosstalk in the brain and identifying emerging research areas. Understanding these interactions offers new insights into brain vascular disease pathogenesis and may inform future strategies for intervention.

The cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway plays a pivotal role in mounting an innate immune response against invading pathogens. Activation of this pathway by exogenous or endogenous stimuli triggers the downstream production of interferons and both pro-/anti-inflammatory cytokines. Over the past decade, hundreds of patents have been filed for the development and use of natural and synthetic STING agonists. For antivirals, synthetic STING agonists have been shown to be effective in both prophylactic and anaphylactic manners against viral infection and serve as vaccine adjuvants. This review summarizes the current application of STING agonists as antivirals to date against a variety of RNA and DNA viruses.

Phosphoinositides are transient signaling lipids, derived from the reversible phosphorylation of phosphatidylinositol on intracellular membranes, which serve as master regulators of many essential cellular functions. Seven distinct phosphoinositide species require precise spatiotemporal control, which is regulated by specific phosphatidylinositol kinases and phosphatases. Here, we review one such family, the inositol polyphosphate 5-phosphatases, which comprise 10 mammalian enzymes that dephosphorylate the 5-position phosphate group from the inositol head group of PtdIns(4,5)P₂, PtdIns(3,5)P₂, and/or PtdIns(3,4,5)P₃. Despite overlapping substrate specificities, the 5-phosphatases play nonredundant roles, including in development, as demonstrated by murine and zebrafish knockout studies. Mutations in several 5-phosphatase family members are associated with multisystem developmental and congenital syndromes. Associations between 5-phosphatase gene variants and diabetes and metabolic syndrome, neurodegenerative disease, and in rare cases cancer, are also emerging. Here, we provide a comprehensive discussion of the latest advances in this field, including updates on disease modeling and mechanisms.

Brain organoids, as self-organizing three-dimensional in vitro systems, offer a significant advantage over traditional models by enabling longitudinal analysis of developing human tissues. Their dynamic nature allows for the investigation of biological processes across time, a crucial 'fourth dimension' often lacking in highly reductionist in vitro models and essential to comprehensively study evolutionary and pathogenetic processes. Furthermore, the inherent genetic amenability of organoids facilitates the integration of advanced technologies, creating novel opportunities to exploit synthetic biology tools. In this regard, novel lineage tracing systems that integrate omics technologies are now dissecting complex human biological processes with unprecedented resolution. This review presents the current state of the art regarding the application of brain organoids for understanding human developmental processes related to cell lineage and temporal progression, highlighting studies that have developed dedicated lineage tracing tools. We further discuss the limitations inherent in current technologies and the potential improvements required to advance their fidelity, scalability, and translational relevance in modeling human brain development and disease.

Interleukin (IL) receptors play a pivotal role in immune regulation through coordinated interactions among multiple receptor subunits. Their cognate ligands, interleukins, orchestrate diverse immune responses by engaging distinct subunit combinations. Here, we developed a programmable IL-2 receptor surrogate ligand using a combinatorial bispecific agonist antibody strategy. By employing two complementary cell-based reporter systems that simultaneously monitor IL-2 receptor-mediated STAT5 activation and cell proliferation, we engineered a surrogate IL-2 receptor ligand that exhibits biased activation and differentiation of effector T and NK cells. This modular approach enables the development of tailored cytokine receptor surrogates with customized immunomodulatory functions.

Despite numerous studies, the biological and medical significance of inositol phosphates (InsPs) remains to be fully elucidated. One of the primary rate-limiting factors for InsP research is the difficulty in developing a method to specifically detect these molecules in complex biological matrices. Recent remarkable advancements in analytical chemistry such as nuclear magnetic resonance spectroscopy, mass spectrometry, and pertinent separation technologies have allowed the selective and sensitive differentiation of InsPs depending on the number and/or position of phosphate groups bound to the inositol ring. Thus, knowledge and experience of analytical chemistry have increasingly become a prerequisite for InsP studies. Establishing synthetic processes for functional InsPs and their analogs by organic chemists has also provided effective tools for quantitating their absolute abundances, as well as for investigating their molecular functions. This review briefly recapitulates the historical trajectory of the methodology applied to InsP research and highlights recently developed protocols using mass spectrometry coupled with liquid chromatography and capillary electrophoresis, in addition to a simple description of the chemical and chemoenzymatic synthesis of InsPs and their analogs.

The Gram-negative pathogen Burkholderia pseudomallei possesses multiple resistance-nodulation-division superfamily transporters that contribute to multidrug resistance, including BpeB and BpeF. Structural studies of BpeB and BpeF have identified a hydrophilic patch in their substrate-binding pocket. To investigate the relationship between this hydrophilic patch and substrate specificity, mutant analyses were performed using an Escherichia coli recombinant expression system. Drug susceptibility tests of BpeB and BpeF mutants showed up to a 64-fold increase in susceptibility compared with the wild type. Growth curve analyses revealed that BpeB mutants exhibited increased resistance to aminoglycosides, which are not transported by the wild type. These findings suggest that the hydrophilic patches in the substrate-binding pockets of BpeB and BpeF are involved in the substrate specificity.

Programmed cell death-1 (PD-1)/programmed death-ligand 1 (PD-L1) checkpoint signaling and its blockade by checkpoint inhibitors are dependent on molecular interactions at the binding interface. In this work, the two complete complex structures in the protein native state of PD-1 with PD-L1, and the anti-PD-L1 antibody atezolizumab were investigated by atomic force microscopy (AFM) single-molecule force spectroscopy and predicted by AlphaFold modeling. AFM revealed that the PD-1/PD-L1 binding interface displayed greater stability than the atezolizumab/PD-L1 complex due to hydrogen bonding, while the hydrophobic effect enhanced binding flexibility at the atezolizumab/PD-L1 interface. The two complexes exhibited different bond lifetimes reflecting binding interface stability and transition distance related to the interface flexibility. This work provides relevant methodology to evaluate single-molecule macromolecular interactions. Impact statement Our research developed a novel and close-to-native physiological platform to evaluate protein interactions from structural, mechanical, and kinetic perspectives at the single-molecule level. This could be applied in the design of more effective checkpoint inhibitory molecules and provides relevant methodologies for evaluating single-molecule macromolecular interactions.

CLOCK, BMAL1, and HIFs are basic helix-loop-helix and Per-Arnt-Sim domain (bHLH-PAS) proteins, which function as transcription factors. bHLH-PAS proteins are designated in two classes. Many class I proteins are regulated by environmental signals via their PAS domains, but such signals have not been identified for all. Class II (ARNTs and BMALs) are partners for Class I and can be regulated by synthetic PAS ligands. Previous studies suggested restricted dimerization for bHLH-PAS proteins. BMAL1 and BMAL2 were believed to dimerize only with CLOCK and NPAS2, while ARNT was thought to dimerize with most Class I proteins except for CLOCK and NPAS2. The logic underlying these assumptions was flawed, and evidence supports dimerization of both HIF1α and HIF2α with BMAL1.