A Near-Infrared Probe for Specific Imaging of Lipid Droplets in Living Cells.

Lipid droplets (LDs) are involved in various physiological processes and associated with cancer development, and are regarded as a potential tumor marker for cancer diagnosis. Monitoring LDs is of prior importance to understand their involvement in biological mechanisms and the early detection of cancers. Highly sensitive and specific noninvasive fluorescent probes are particularly desirable for imaging LDs and cancer diagnosis. Herein, according to the high-viscosity and low-polarity microenvironment in LDs, we developed four easily prepared LDs-specific probes based on noncharged merocyanines. Among them, LD-1 absorbs and emits in the near-infrared (NIR) region with a large Stokes shift. Importantly, LD-1 displayed high sensitivity to high viscosity and low polarity, which allowed it to show high LDs-targeting ability. In cell imaging, LD-1 successfully probed the changes in LDs in the presence of oleic acid or during ferroptosis and was used to distinguish cancer cells from normal cells.

BLISTER promotes seed maturation and fatty acid biosynthesis by interacting with WRINKLED1 to regulate chromatin dynamics in Arabidopsis.

WRINKLED1 (WRI1) is an important transcription factor that regulates seed oil biosynthesis. However, how WRI1 regulates gene expression during this process remains poorly understood. Here, we found that BLISTER (BLI) is expressed in maturing Arabidopsis thaliana seeds and acts as an interacting partner of WRI1. bli mutant seeds showed delayed maturation, a wrinkled seed phenotype, and reduced oil content, similar to the phenotypes of wri1. In contrast, BLI overexpression resulted in enlarged seeds and increased oil content. Gene expression and genetic analyses revealed that BLI plays a role in promoting the expression of WRI1 targets involved in fatty acid biosynthesis and regulates seed maturation together with WRI1. BLI is recruited by WRI1 to the AW boxes in the promoters of fatty acid biosynthesis genes. BLI shows a mutually exclusive interaction with the Polycomb-group protein CURLY LEAF (CLF) or the chromatin remodeling factor SWITCH/SUCROSE NONFERMENTING 3B (SWI3B), which facilitates gene expression by modifying nucleosomal occupancy and histone modifications. Together, these data suggest that BLI promotes the expression of fatty acid biosynthesis genes by interacting with WRI1 to regulate chromatin dynamics, leading to increased fatty acid production. These findings provide insights into the roles of the WRI1-BLI-CLF-SWI3B module in mediating seed maturation and gene expression.

Screening of dicyanoisophorone-based probes for highly sensitive detection of viscosity changes in living cells and zebrafish.

Herein, seven viscosity-sensitive probes were developed via simple structural modification of dicyanoisophorone (DCO)-derived dyes. Among them, DCO-5 significantly enhances (180-fold) the response signal in highly viscous aqueous media while showing insensitivity to polarity changes or pH variations, and enables the successful detection of viscosity changes in nystatin-treated HepG2 cells, PC 12 cells and zebrafish.

A "double-locked" probe for the detection of hydrogen sulfide in a viscous system.

A novel "double-locked" probe, DCO-H2S-V, was prepared for detecting hydrogen sulfide in a highly viscous system. Experiments demonstrated that only when H2S and a high viscosity environment coexist in a cell, can the probe be activated effectively and emit fluorescence. This has been successfully used for detecting the changes in viscosity and H2S in a Parkinson's disease model, PC-12 cells treated with glutamate.

Correction: A "double-locked" probe for the detection of hydrogen sulfide in a viscous system.

Correction for 'A "double-locked" probe for the detection of hydrogen sulfide in a viscous system' by Fanpeng Kong et al., Chem. Commun., 2021, DOI: 10.1039/d1cc01819a.