Lysine lactylation (Kla) is a recently discovered histone mark derived from metabolic lactate. The NAD + -dependent deacetylase SIRT3, which can also catalyze removal of the lactyl moiety from lysine, is expressed at low levels in hepatocellular carcinoma (HCC) and has been suggested to be an HCC tumor suppressor. Here we report that SIRT3 can delactylate non-histone proteins and suppress HCC development. Using SILAC-based quantitative proteomics, we identify cyclin E2 (CCNE2) as one of the lactylated substrates of SIRT3 in HCC cells. Furthermore, our crystallographic study elucidates the mechanism of CCNE2 K348la delactylation by SIRT3. Our results further suggest that lactylated CCNE2 promotes HCC cell growth, while SIRT3 activation by Honokiol induces HCC cell apoptosis and prevents HCC outgrowth in vivo by regulating Kla levels of CCNE2. Together, our results establish a physiological function of SIRT3 as a delactylase that is important for suppressing HCC, and our structural data could be useful for the future design of activators.

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The fungus gnat Bradysia impatiens (Johannsen) is a worldwide pest inhabiting organicrich environments, including mushroom-cultivation substrates, which leads to massive production losses of edible mushrooms. To promote a non-insecticidal pest control strategy, we evaluated adult behavioural response towards two saprophytic fungal strains Aspergillus flavus Link and Mucor circinelloides Tiegh., isolated from B. impatiensinhabiting substrates and six edible mushrooms species. Our results indicated that (a) B. impatiens was most attracted to the oyster mushroom Pleurotus ostreatus among all six edible mushrooms; (b) males and females demonstrated a significant attraction for M. circinelloides over A. flavus and P. ostreatus; (c) adults demonstrated dynamic attraction tendencies that varied with the culture periods of A. flavus and M. circinelloides, wherein females represented most (mean = 78.6%) of the attracted individuals; and (d) larvae that fed on mycelial cultures of M. circinelloides could complete their entire life cycles, but larvae could not survive on a non-fungal or A. flavus diet. These results demonstrate the potential for the development of M. circinelloides in a push-pull strategy to biocontrol this pest in edible mushroom cultivation.

Annual herbaceous plants are frequently layered under the artificial sand-fixing forest within the desert oasis transition zone of the Hexi Corridor. The effect of drought stress on annual herbaceous plants is of great significance to the restoration of artificial vegetation as well as the stability of the ecosystem in the desert oasis transition zone. Setaria viridis, Chloris virgata, Halogeton arachnoideus, and Bassia dasyphylla are the typical annual herbaceous plants that occur naturally in the Caragana korshinskii forest and were used as the research subject in this study. Concentration gradient tests were conducted under different mixed growth conditions: 0 (blank control group), 5, 10, and 15 C. korshinskii seeds, and different drought stress conditions: 0%, 2%, 5%, 10%, and 15%, in order to explore the interactive effects of drought stress on annual herbaceous plants. The results demonstrated that the germination percentage and germination rate of annual herbaceous plants was significantly affected by the number of C. korshinskii seeds (p < 0.05), whereby the germination effect was optimal when no C. korshinskii seeds were present. Furthermore, we found that the germination percentage and germination rate of the annual Gramineae was higher than that of the Chenopods. In the growth stage, the biomass and root-shoot ratio of the chenopods were significantly affected by the number of C. korshinskii seeds and drought stress (p < 0.05). We found that the biomass of annual herbaceous plants was the highest at 2% drought stress, and the root-shoot ratio displayed a positive correlation with an increase in drought stress. Notably, the survival rate of annual herbaceous plants was higher when grown in combination with five C. korshinskii seeds, thus indicating a positive interaction; in contrast, the survival rate decreased significantly when they were grown in combination with more than five C. korshinskii seeds, indicating a negative interaction. We observed a decreasing trend in root activity and chlorophyll content when annual herbaceous plants were grown in combination with an increasing number of C. korshinskii seeds and drought stress. The reduced root activity and decline in photosynthetic ability resulted in the inhibition of seedling growth. Furthermore, we found that the root activity and chlorophyll content of the Gramineae was ~1.3–2.0 times higher than that of the Chenopods, which may be the reason behind the lower survival rate of the chenopods.