scholarly journals ZMYND8 mediated liquid condensates spatiotemporally decommission the latent super-enhancers during macrophage polarization

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Pan Jia ◽  
Xiang Li ◽  
Xuelei Wang ◽  
Liangjiao Yao ◽  
Yingying Xu ◽  
...  

AbstractSuper-enhancers (SEs) govern macrophage polarization and function. However, the mechanism underlying the signal-dependent latent SEs remodeling in macrophages remains largely undefined. Here we show that the epigenetic reader ZMYND8 forms liquid compartments with NF-κB/p65 to silence latent SEs and restrict macrophage-mediated inflammation. Mechanistically, the fusion of ZMYND8 and p65 liquid condensates is reinforced by signal-induced acetylation of p65. Then acetylated p65 guides the ZMYND8 redistribution onto latent SEs de novo generated in polarized macrophages, and consequently, recruit LSD1 to decommission latent SEs. The liquidity characteristic of ZMYND8 is critical for its regulatory effect since mutations coagulating ZMYND8 into solid compartments disable the translocation of ZMYND8 and its suppressive function. Thereby, ZMYND8 serves as a molecular rheostat to switch off latent SEs and control the magnitude of the immune response. Meanwhile, we propose a phase separation model by which the latent SEs are fine-tuned in a spatiotemporal manner.

Author(s):  
Liam M. Longo ◽  
Dragana Despotović ◽  
Orit Weil-Ktorza ◽  
Matthew J. Walker ◽  
Jagoda Jabłońska ◽  
...  

AbstractDe novo emergence, and emergence of the earliest proteins specifically, demands a transition from disordered polypeptides into structured proteins with well-defined functions. However, can peptides confer evolutionary relevant functions, let alone with minimal abiotic amino acid alphabets? How can such polypeptides evolve into mature proteins? Specifically, while nucleic acids binding is presumed a primordial function, it demands basic amino acids that do not readily form abiotically. To address these questions, we describe an experimentally-validated trajectory from a phase-separating polypeptide to a dsDNA-binding protein. The intermediates comprise sequence-duplicated, functional proteins made of only 10 amino acid types, with ornithine, which can form abiotically, as the only basic amino acid. Statistical, chemical modification of ornithine sidechains to arginine promoted structure and function. The function concomitantly evolved – from phase separation with RNA (coacervates) to avid and specific dsDNA binding – thereby demonstrating a smooth, gradual peptide-to-protein transition with respect to sequence, structure, and function.


Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1825
Author(s):  
Mohamed Zeineldin ◽  
Ameer Megahed ◽  
Benjamin Blair ◽  
Brian Aldridge ◽  
James Lowe

The gastrointestinal microbiome plays an important role in swine health and wellbeing, but the gut archaeome structure and function in swine remain largely unexplored. To date, no metagenomics-based analysis has been done to assess the impact of an early life antimicrobials intervention on the gut archaeome. The aim of this study was to investigate the effects of perinatal tulathromycin (TUL) administration on the fecal archaeome composition and diversity in suckling piglets using metagenomic sequencing analysis. Sixteen litters were administered one of two treatments (TUL; 2.5 mg/kg IM and control (CONT); saline 1cc IM) soon after birth. Deep fecal swabs were collected from all piglets on days 0 (prior to treatment), 5, and 20 post intervention. Each piglet’s fecal archaeome was composed of rich and diverse communities that showed significant changes over time during the suckling period. At the phylum level, 98.24% of the fecal archaeome across all samples belonged to Euryarchaeota. At the genus level, the predominant archaeal genera across all samples were Methanobrevibacter (43.31%), Methanosarcina (10.84%), Methanococcus (6.51%), and Methanocorpusculum (6.01%). The composition and diversity of the fecal archaeome between the TUL and CONT groups at the same time points were statistically insignificant. Our findings indicate that perinatal TUL metaphylaxis seems to have a minimal effect on the gut archaeome composition and diversity in sucking piglets. This study improves our current understanding of the fecal archaeome structure in sucking piglets and provides a rationale for future studies to decipher its role in and impact on host robustness during this critical phase of production.


Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 868
Author(s):  
Fabiana Albani Zambuzi ◽  
Priscilla Mariane Cardoso-Silva ◽  
Ricardo Cardoso Castro ◽  
Caroline Fontanari ◽  
Flavio da Silva Emery ◽  
...  

Decitabine is an approved hypomethylating agent used for treating hematological malignancies. Although decitabine targets altered cells, epidrugs can trigger immunomodulatory effects, reinforcing the hypothesis of immunoregulation in treated patients. We therefore aimed to evaluate the impact of decitabine treatment on the phenotype and functions of monocytes and macrophages, which are pivotal cells of the innate immunity system. In vitro decitabine administration increased bacterial phagocytosis and IL-8 release, but impaired microbicidal activity of monocytes. In addition, during monocyte-to-macrophage differentiation, treatment promoted the M2-like profile, with increased expression of CD206 and ALOX15. Macrophages also demonstrated reduced infection control when exposed to Mycobacterium tuberculosis in vitro. However, cytokine production remained unchanged, indicating an atypical M2 macrophage. Furthermore, when macrophages were cocultured with lymphocytes, decitabine induced a reduction in the release of inflammatory cytokines such as IL-1β, TNF-α, and IFN-γ, maintaining IL-10 production, suggesting that decitabine could potentialize M2 polarization and might be considered as a therapeutic against the exacerbated immune response.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Javier Emperador-Melero ◽  
Man Yan Wong ◽  
Shan Shan H. Wang ◽  
Giovanni de Nola ◽  
Hajnalka Nyitrai ◽  
...  

AbstractThe active zone of a presynaptic nerve terminal defines sites for neurotransmitter release. Its protein machinery may be organized through liquid–liquid phase separation, a mechanism for the formation of membrane-less subcellular compartments. Here, we show that the active zone protein Liprin-α3 rapidly and reversibly undergoes phase separation in transfected HEK293T cells. Condensate formation is triggered by Liprin-α3 PKC-phosphorylation at serine-760, and RIM and Munc13 are co-recruited into membrane-attached condensates. Phospho-specific antibodies establish phosphorylation of Liprin-α3 serine-760 in transfected cells and mouse brain tissue. In primary hippocampal neurons of newly generated Liprin-α2/α3 double knockout mice, synaptic levels of RIM and Munc13 are reduced and the pool of releasable vesicles is decreased. Re-expression of Liprin-α3 restored these presynaptic defects, while mutating the Liprin-α3 phosphorylation site to abolish phase condensation prevented this rescue. Finally, PKC activation in these neurons acutely increased RIM, Munc13 and neurotransmitter release, which depended on the presence of phosphorylatable Liprin-α3. Our findings indicate that PKC-mediated phosphorylation of Liprin-α3 triggers its phase separation and modulates active zone structure and function.


Author(s):  
Jonathon A Ditlev

Abstract Liquid‒liquid phase separation (LLPS) of biomolecules has emerged as an important mechanism that contributes to cellular organization. Phase separated biomolecular condensates, or membrane-less organelles, are compartments composed of specific biomolecules without a surrounding membrane in the nucleus and cytoplasm. LLPS also occurs at membranes, where both lipids and membrane-associated proteins can de-mix to form phase separated compartments. Investigation of these membrane-associated condensates using in vitro biochemical reconstitution and cell biology has provided key insights into the role of phase separation in membrane domain formation and function. However, these studies have generally been limited by available technology to study LLPS on model membranes and the complex cellular environment that regulates condensate formation, composition, and function. Here, I briefly review our current understanding of membrane-associated condensates, establish why LLPS can be advantageous for certain membrane-associated condensates, and offer a perspective for how these condensates may be studied in the future.


2017 ◽  
Vol 204 (5-6) ◽  
pp. 293-303 ◽  
Author(s):  
Masatoshi Fujita ◽  
Tadasu Sato ◽  
Takehiro Yajima ◽  
Eiji Masaki ◽  
Hiroyuki Ichikawa

TRPC (transient receptor potential cation channel subfamily C) members are nonselective monovalent cation channels and control Ca2+ inflow. In this study, immunohistochemistry for TRPC1, TRPC3, and TRPC4 was performed on rat oral and craniofacial structures to elucidate their distribution and function in the peripheries. In the trigeminal ganglion (TG), 56.1, 84.1, and 68.3% of sensory neurons were immunoreactive (IR) for TRPC1, TRPC3, and TRPC4, respectively. A double immunofluorescence method revealed that small to medium-sized TG neurons co-expressed TRPCs and calcitonin gene-related peptide. In the superior cervical ganglion, all sympathetic neurons showed TRPC1 and TRPC3 immunoreactivity. Parasympathetic neurons in the submandibular ganglion, tongue, and parotid gland were TRPC1, TRPC3, and TRPC4 IR. Gustatory and olfactory cells were also IR for TRPC1, TRPC3, and/or TRPC4. In the musculature, motor endplates expressed TRPC1 and TRPC4 immunoreactivity. It is likely that TRPCs are associated with sensory, autonomic, and motor functions in oral and craniofacial structures.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Huihui Li ◽  
Mingzhe Xie ◽  
Yan Wang ◽  
Ludong Yang ◽  
Zhi Xie ◽  
...  

AbstractriboCIRC is a translatome data-oriented circRNA database specifically designed for hosting, exploring, analyzing, and visualizing translatable circRNAs from multi-species. The database provides a comprehensive repository of computationally predicted ribosome-associated circRNAs; a manually curated collection of experimentally verified translated circRNAs; an evaluation of cross-species conservation of translatable circRNAs; a systematic de novo annotation of putative circRNA-encoded peptides, including sequence, structure, and function; and a genome browser to visualize the context-specific occupant footprints of circRNAs. It represents a valuable resource for the circRNA research community and is publicly available at http://www.ribocirc.com.


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