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Organisms respond to tissue damage through the upregulation of protective responses which restore tissue structure and metabolic function. Mitochondria are key sources of intracellular oxidative metabolic signals that maintain cellular homeostasis. Here we report that tissue and cellular wounding triggers rapid and reversible mitochondrial fragmentation. Elevated mitochondrial fragmentation either in fzo-1 fusion-defective mutants or after acute drug treatment accelerates actin-based wound closure. Wounding triggered mitochondrial fragmentation is independent of the GTPase DRP-1 but acts via the mitochondrial Rho GTPase MIRO-1 and cytosolic Ca2+. The fragmented mitochondria and accelerated wound closure of fzo-1 mutants are dependent on MIRO-1 function. Genetic and transcriptomic analyzes show that enhanced mitochondrial fragmentation accelerates wound closure via the upregulation of mtROS and Cytochrome P450. Our results reveal how mitochondrial dynamics respond to cellular and tissue injury and promote tissue repair.

This paper presents a practical and efficient strategy for the preparation of imidazol[2,1‐b]‐thiazoles from thioimidazoles and ketones mediated by Selectfluor. The proposed mechanism suggests that this transformation took place through electrophilic thiolation at an α‐carbon of ketones by sulfur cation, which is produced by the oxidation of thioimidazole by Selectfluor. This metal‐free protocol tolerated various ketones, including methyl ketones or non‐methyl ketones, aryl ketones or aliphatic ketones. The experimental results indicated that steric hindrance of the substituents at the α‐position of ketones or on the aromatic ring of aryl ketones had significant influence on the yields of imidazol[2,1‐b]‐thiazoles. Thioimidazole and benzothioimidazoles were well tolerated while 5‐substituted benzothioimidazoles provided the mixture of the corresponding 6‐substituted and 7‐substituted benzoimidazo[2,1‐b]thiazole products. [ABSTRACT FROM AUTHOR]

A three‐component transition‐metal‐free aerobic method for the generation of 1,4‐benzothiazines is reported herein. The KI/DMSO/O2 system was found to be effective for the oxidative cyclization/coupling of 2‐aminobenzenethiols, anilines, and methylketones. Hence, various structurally important imino 1,4‐benzothiazines were assembled with broad functional group tolerance. Mechanistic studies revealed an initial oxidation of ketone α C−H bonds by the KI/DMSO/O2 oxidative system. [ABSTRACT FROM AUTHOR]

We report a green and regioselective process for the construction of benzoimidazo[2,1‐b]thiazole skeletons in water using DMSO/H2O2 as an oxidant. The experimental data lend support to a mechanism in which the transformation is initiated by oxidizing methylene of ketone into carbon radical under the oxidation of DMSO/H2O2. This operationally simple and metal‐free procedure could facilitate a diverse collection of benzoimidazo[2,1‐b]thiazole derivatives. [ABSTRACT FROM AUTHOR]

[image omitted] 4-Methylene-1,3-oxazolidin-2-ones were prepared via the cycloadditon reaction of propargylic alcohols with primary amines and CO2 under atmospheric pressure at 60 °C in the absence of any additional solvent. This methodology affords an ecofriendly, mild, and easy approach to chemical fixation of CO2. [ABSTRACT FROM AUTHOR]

Claudin proteins are a major component of the tight junctions between cells, which are involved in a variety of human diseases, including cancer. This study aimed to investigate the functional role of claudin 19 (CLDN19) in human breast cancer progression. Here, we firstly found that CLDN19 was downregulated in breast tumor tissues than normal control, and loss of CLDN19 predicted poor patient survival in patients with breast cancer, by utilizing the Cancer Genome Atlas Program (TCGA) dataset analysis. To further validate the tumor suppressive effects of CLDN19, we established CLDN19 overexpressed MDA-MB-231 and T47D cells. And overexpression of CLDN19 resulted in suppression of cell growth/migration in breast cancer cells cultured in 3D environment or in vivo . Mechanistically, we demonstrated that CLDN19 downregulated ubiquitin conjugating enzyme E2 C (UBE2C) expression, which further suppressed Wnt/β-catenin pro-survival signaling pathway activation induced by extracellular matrix (ECM), in 3D environment or in vivo . Altogether, our study revealed a tumor suppressive role of CLDN19, which hindered ECM/UBE2C/Wnt signaling activation in breast cancer, and offered novel insight for tumor diagnosis and targeted therapy., Competing Interests: None., (AJCR Copyright © 2022.)