Structural and functional regulation of Chlamydomonas lysosome-related organelles during environmental changes.

Lysosome-related organelles (LROs) are a class of heterogeneous organelles conserved in eukaryotes that primarily play a role in storage and secretion. An important function of LROs is to mediate metal homeostasis. Chlamydomonas reinhardtii is a model organism for studying metal ion metabolism; however, structural and functional analyses of LROs in C. reinhardtii are insufficient. Here, we optimized a method for purifying these organelles from 2 populations of cells: stationary phase or overloaded with iron. The morphology, elemental content, and lysosomal activities differed between the 2 preparations, even though both have phosphorus and metal ion storage functions. LROs in stationary phase cells had multiple non-membrane-bound polyphosphate granules to store phosphorus. Those in iron-overloaded cells were similar to acidocalcisomes (ACs), which have a boundary membrane and contain 1 or 2 large polyphosphate granules to store more phosphorus. We established a method for quantifying the capacity of LROs to sequester individual trace metals. Based on a comparative proteomic analysis of these 2 types of LROs, we present a comprehensive AC proteome and identified 113 putative AC proteins. The methods and protein inventories provide a framework for studying the biogenesis and modification of LROs and the mechanisms by which they participate in regulating metal ion metabolism.

Analysis of hyperforin (St. John's wort) action at TRPC6 channel leads to the development of a new class of antidepressant drugs.

St. John's wort is an herb, long used in folk medicine for the treatment of mild depression. Its antidepressant constituent, hyperforin, has properties such as chemical instability and induction of drug-drug interactions that preclude its use for individual pharmacotherapies. Here we identify the transient receptor potential canonical 6 channel (TRPC6) as a druggable target to control anxious and depressive behavior and as a requirement for hyperforin antidepressant action. We demonstrate that TRPC6 deficiency in mice not only results in anxious and depressive behavior, but also reduces excitability of hippocampal CA1 pyramidal neurons and dentate gyrus granule cells. Using electrophysiology and targeted mutagenesis, we show that hyperforin activates the channel via a specific binding motif at TRPC6. We performed an analysis of hyperforin action to develop a new antidepressant drug that uses the same TRPC6 target mechanism for its antidepressant action. We synthesized the hyperforin analog Hyp13, which shows similar binding to TRPC6 and recapitulates TRPC6-dependent anxiolytic and antidepressant effects in mice. Hyp13 does not activate pregnan-X-receptor (PXR) and thereby loses the potential to induce drug-drug interactions. This may provide a new approach to develop better treatments for depression, since depression remains one of the most treatment-resistant mental disorders, warranting the development of effective drugs based on naturally occurring compounds.

[Synthesis, biological activity, computer aided drug design of alpha-pinene derivatives].

Based on the anticancer mechanism of biological alkylating agent, we designed and synthesized two alpha pinene derivatives:(1R,5S)-(6,6-dimethylbicyclo[3,1,1]hept-2-en-2-yl)methyl benzenesulfonate and (1R,5S)-(6,6-dimethylbicyclo[3,1,1]hept-2-en-2-yl)methyl 4-methylbenzenesulfonate, of which structures were confirmed by ¹H-NMR, HPLC and MS date. These two compounds showed a good inhibition of tumor cells' proliferation. Further, the computer siuulation of molecular docking and metabolic kinetics indicated that these two copounds may have stable molecular complexation with protein CDK2, which closely related to the cell cycle.

[Study on difference of functional components content of different Rheum tanguticum variation type].

Rheum tanguticum from the same area was divided into 8 types of variation according to the plant morphology, content differences of free anthraquinones, combined anthraquinones, double anthrone were studied. The results showed that the functional components of different variation types were significantly different. The average content of free anthraquinone combined anthraquinone was 2.10-6.71 and 15.43-22.04 mg•g⁻¹, respectively. The average content of sennoside A plus sennoside B was 32.88-42.36 mg•g⁻¹. There were significant differences among the difference of 10 kinds of active components, except for sennoside B and physcion glycoside. Interred with the content and proportion of functional components, type B and type E might be potential special medicinal germplasm for diarrhea attack product, type G and type H might be a potential special medicinal germplasm for clearing heat and detoxifing, type C and type F might be potential special medicinal germplasm for activating blood circulation to dissipate blood stasis, type A and type D might be potential special medicinal germplasm with anastaltic funtion. The conclusion laid the foundation for the directional cultivation of fine varieties of special purpose of rhubarb.