Genome-Wide Identification and Characterization of the Salvia miltiorrhiza Histone Deacetylase (HDAC) Family in Response to Multiple Abiotic Stresses.

Salvia miltiorrhiza is a plant commonly used in traditional Chinese medicine. Its material bases for treating diseases are tanshinones and phenolic acids, including salvianolic acids. Histone deacetylase proteins (HDACs) are a class of specific functional enzymes that interact with acetylation groups on the N-terminal lysine of histone proteins further regulate gene transcription through structural changes at the chromatin level. HDACs involved in the growth and development of various plants, and induced by plant hormones to regulate the internal environment of plants to resist stress, at the same time affect the accumulation of some secondary metabolites. However, the role of SmHDACs on the accumulation of salvianolic acid in S. miltiorrhiza remains unclear. In this study, 16 SmHDACs genes were identified from the high-quality S. miltiorrhiza genome, their physicochemical properties were predicted. In phylogenetic trees co-constructed with HDACs proteins from other plants, SmHDACs was divided into three subfamilies, each with similar motif and conserved domain composition. The distribution of the three subfamilies is similar to that of dicotyledonous plants. Chromosome localization analysis showed that SmHDACs genes were randomly located. Cis-acting element analysis predicted that SmHDACs gene expression may be related to and induced by various phytohormones, such as MeJA and ABA. By combining the expression pattern and co-expression network induced by phytohormones, we speculate that SmHDACs may further influence the synthesis of salvianolic acid, and identified SmHDA5, a potential functional gene, then speculate its downstream target based on the co-expression network. In summary, we analyzed the SmHDACs gene family of S. miltiorrhiza and screened out the potential functional gene SmHDA5. From the perspective of epigenetics, we proposed the molecular mechanism of plant hormone promoting salvianolic acid synthesis, which filled the gap in the subdivision of histone deacetylase in S. miltiorrhiza research, provided a theoretical basis for the culture and transformation of S. miltiorrhiza germplasm resources.

Light-enhanced hypoxia-responsive and azobenzene cleavage-triggered size-shrinkable micelles for synergistic photodynamic therapy and chemotherapy.

Hypoxia is an important pathological phenomenon due to uncontrolled cancer cell proliferation and insufficient blood flow, which can be used to design hypoxia-responsive nanocarriers for the intelligent treatment of tumor. However, it is difficult to obtain the response of hypoxia-responsive polymers corresponding to the degree of hypoxia in the tumor sites. Therefore, hypoxia-responsive azobenzene-centered copolymers polyoligo (ethylene glycol) methacrylate-block-poly(ε-caprolactone)-azobenzene-poly(ε-caprolactone)-block-poly oligo (ethylene glycol) (POEGMA-b-PCL-Azo-PCL-b-POEGMA) were synthesized and further self-assembled into spherical micelles. Doxorubicin (DOX) and chlorine e6 (Ce6) were encapsulated inside the micelles. The photodynamic therapy (PDT) of Ce6 could be applied to further amplify the hypoxia condition in the tumor sites through oxygen consumption on laser irradiation (660 nm). Under this condition, the DOX/Ce6-loaded micelles progressively formed spherical micelles with a small size due to the cleavage of azobenzene, thus allowing the controlled release of DOX. The formed smaller micelles could significantly avoid the formation of large aggregates, which is beneficial for clinical application. Moreover, Ce6 would continuously convert oxygen to singlet oxygen (1O2), thus showing toxicity to cancer cells. Both in vitro and intracellular studies confirmed that our "all-in-one" micelles showed a superior synergistic effect of photodynamic therapy and chemotherapy.

Cellulosic sponges with pH responsive wettability for efficient oil-water separation.

To obtain efficient oil-water separation materials with responsiveness, cellulosic porous materials with switchable wettability in response to pH changes were developed by reacting cellulose acetoacetate sponges with alkylamines of varying carbon chain length via dynamic covalent enamine bonds. The resulting sponges reversibly changed between being superhydrophilic (θwater = 0°) and highly hydrophobic (maximal θwater = 146°) under suitable pH conditions while maintained the favorable porous structures. Notably, the functionalized sponges exhibited high and selective oil absorption capacity (40-80 g/g) and satisfying desorption ability of 80%, and could efficiently separate oil-water mixtures and emulsions with extremely high efficiency (> 99%) in a controllable manner. With the three-dimensional micro/nano porous structure, switchable wettability and intrinsic environmentally friendliness, the pH responsive cellulosic sponges developed here hold great potential in controllable oil-water separation and oily wastewater purification.