The Loss of YTHDC1 in Gut Macrophages Exacerbates Inflammatory Bowel Disease.

The nuclear N6 -methyladenosine (m6 A) reader YT521-B homology-domain-containing protein 1 (YTHDC1) is required to maintain embryonic stem cell identity. However, little is known about its biological functions in intestinal-resident macrophages and inflammatory bowel disease (IBD). Herein, it is demonstrated that macrophage-specific depletion or insufficiency of YTHDC1 accelerates IBD development in animal models. On the molecular basis, YTHDC1 reduction in IBD-derived macrophages is attributed to Zinc finger protein 36 (ZFP36)-induced mRNA degradation. Importantly, transcriptome profiling and mechanistic assays unveil that YTHDC1 in macrophages regulates Ras homolog family member H (RHOH) to suppress inflammatory responses and fine-tunes NME nucleoside diphosphate kinase 1 (NME1) to enhance the integrity of colonic epithelial barrier, respectively. Collectively, this study identifies YTHDC1 as an important factor for the resolution of inflammatory responses and restoration of colonic epithelial barrier in the setting of IBD.

High-strain sensitive zwitterionic hydrogels with swelling-resistant and controllable rehydration for sustainable wearable sensor.

The irrecoverability of mechanical strength, conductivity and other properties after dehydration, has severely restricted the practical applications of hydrogels. To address this issue, here we report a P(AA-SMA-SBMA) zwitterionic copolymer-based hydrogel with anti-swelling, high mechanical property and reusability after dehydration/hydration process by polymerization of acrylic acid (AA), octadecyl methacrylate (SMA) and sulfobetaine methacrylate (SBMA). The structures of the original hydrogels and that after dehydration/hydration cycles were characterized by SAXS, SEM, Raman, FT-IR, XRD, DSC and rheology, etc. It was proved that both the macroscopic properties and the micro-structures were maintained after several dehydration/hydration cycles, owing to the synergistic effects of hydrophobic and super-hydrophilic interaction in the 3D network structure. Moreover, the fabricated hydrogels possess high strain sensitivity which is applied to monitor both junction motion and subtle movement like breathing and pulse. In addition, such sensitivity of the hydrogel sensors could be maintained after several dehydration/hydration cycles or even sinking in water for over two months. This work provides a type of hydrogel material with stable properties after dehydration process by regulating hydrophobic and hydrophilic interaction, which is beneficial for the life-time and sustainability of hydrogel devises.

The characterization of two peroxiredoxin genes in Dunaliella viridis provides insights into antioxidative response to salt stress.

Peroxiredoxins (Prxs), a group of antioxidant enzymes, are an important component of the oxidative defense system and have been demonstrated to function as peroxidases, sensors of H(2)O(2)-mediated signaling and/or chaperones. In this study, a cDNA library was constructed from a halotolerant alga, Dunaliella viridis, and was used in a functional complementation screen for antioxidative genes in an oxidative sensitive yeast mutant. Two Prx genes, DvPrx1 and DvPrx2, were obtained from this screen. These two genes were classified as type II Prx and 2-Cys Prx based on amino acid sequence and phylogenetic analysis. When over-expressed in yeast cells, both Prx genes were able to confer better oxidative tolerance and decrease the level of reactive oxygen species (ROS). Subcellular localization experiments in tobacco cells revealed that both DvPrx1 and DvPrx2 were localized in the cytosol. The transcription of DvPrx1 and DvPrx2 can be induced by hypersalinity shock, but is not obviously affected by treatment with high levels of oxidant. Our results shed light on the function and regulation of Prx genes from Dunaliella and their potential roles in salt tolerance.