Monitoring the pH fluctuation of lysosome under cell stress using a near-infrared ratiometric fluorescent probe

Cell stress responses are associated with numerous diseases including diabetes, neurodegenerative diseases, and cancer. Several events occur under cell stress, in which, are protein expression and organellespecific pH fluctuation. To understand the lysosomal pH variation under cell stress, a novel NIR ratiometric pH-responsive fluorescent probe(BLT) with lysosomes localization capability was developed.The quinoline ring of BLT combined with hydrogen ion which triggered the rearrangement of π electrons conjugated at low pH medium, meanwhile, the absorption and fluorescent spectra of BLT showed a red-shifts, which gived a ratiometric signal. Moreover, the probe BLT with a suitable p Kavalue has the potential to discern changes in lysosomal pH, either induced by heat stress or oxidative stress or acetaminophen-induced(APAP) injury stress. Importantly, this ratiometric fluorescent probe innovatively tracks pH changes in lysosome in APAP-induced liver injury in live cells, mice, and zebrafish. The probe BLT as a novel fluorescent probe possesses important value for exploring lysosomal-associated physiological varieties of drug-induced hepatotoxicity.

Mapping Heterotic Loci for Yield and Agronomic Traits Using Chromosome Segment Introgression Lines in Cotton

In the present study, a set of chromosome segment introgression lines （CSILs） using Gossypium hirsutum L. TM-1 as the recipient parent and G. barbadense Hai7124 as the donor parent were used to explore the genetic basis of heterosis for interspecific hybrids. Two sets of F1 populations individually derived from CSILs crossing with both parents were configured to investigate heterotic loci （HL） and substitution effect loci （SL）. A total of 58 HL and 39 SL were identified in 3 years. One stable HL, hLP-A4-3, could be detected in all 3 years. Three HLs, hBS-A8-1, hLP-D6-1, and hSI-D7-11, could be detected in 2 years. Four SLs, sBSoD7- 1, sLP-A8-1, sLP-D7-1, and sLP-D12-1, could be detected in 2 years. HL and SL tended to be distributed in some HL-rich chromosome segments with close positions. Compared with QTL detected in a former study, HL showed little overlap with QTL, indicating that trait phenotype and heterosis might be controlled by different sets of loci. All three forms of genetic effects （partial-, full-, over-dominant） were identified, while the over-dominant effect made the main contribution to heterosis. These results may help lay the foundation for clarifying the heredity mechanism of heterosis in cotton.

Light-up lipid droplets for the visualization of lipophagy and atherosclerosis by coumarin-derived bioprobe

Lipid droplets(LDs) are intracellular lipid-metabolism organelles that involved in many physiological processes,metabolic disorders as well as diseases such as atherosclerosis.However,the specific probes that can visually locate abnormal LDs-rich tissues and track LDs-associated behavior to the naked eye with adequate biosafety still are rare.Herein,we develop a new design strategy of LDs-targeted probe based on the solvatochromism of coumarin derivatives.The results revealed that the emission wavelength of coumarin fluorophores gradually red shift in different solvents with increasing polarity,while absorption wavelength almost unchanged.As a result,the enlarged stokes shift of coumarin was emerged from oil to water.Furthermore,properly reducing water solubility and adding electronic donor at the structure of coumarins can enlarge this type of solvatochromism.This discovery was utilized to develop suitable probe for the image of LDs and LDs-rich tissues with high resolution and biosafety.Therefore,LDs-associated behavior was visible to the naked eye during the process of lipophagy and atherosclerosis.We deem that the developed probe here offers a new possibility to accurately diagnosis and analyse LDs-related diseases in clinic and preclinical study.