Photosynthetic Characteristics in Two Near Isogenic Lines of Winter Wheat

The development of near isogenic lines(NILs) is an important tool for physiological dissection of drought resistance in wheat. To better understand the potential for improving grain yield, a split-plot experiment was conducted under a mobile rain shelter using NILs of winter wheat with significant differences in the photosynthetic rate: the 908120 line with a high photosynthetic rate and the 908206 line with a low photosynthetic rate. The results indicated that the net photosynthesis rate(Pn), stomatal conductance, and transpiration rate in flag leaves in line 908120 were significantly higher than that in line 908206 under uniform water treatments during the reproductive phase in replicated pooled-culture trials. The maximum quantum yield Fv/Fm value and ribulose-1,5-bisphosphate carboxylase/oxygenase(RuBPCase) activity value were higher in line 908120 than that in line 908206, whereas the intercellular CO_2 and cell membrane permeability in line 908120 were lower than that in line 908206. Higher leaf Pn, transpiration rate, and RuBPCase activity and lower membrane ion leakage rate ensured the robustness of line 908120 during times of irrigation and drought, which contributed to the maintenance of its high grain yield. Drought had a negative effect on these factors, resulting in decreased yield, and the photosynthesis rate of flag leaves markedly affected the yield in NILs of winter wheat. NILs are an important strategy for wheat adaptation to drought stress, but might not be the only mechanism causing the significant grain yield increase. Collectively, the characteristics of line 908120 resulted in a higher grain yield compared with that of line 908206. Further dissection of the drought avoidance mechanisms in wheat, as well as analysis and identification of the genes involved may be necessary.

Discovery and development of tricyclic matrinic derivatives as anti-diabetic candidates by AMPKαactivation

We found compound 12N-p-trifluoromethylbenzenesulfonyl matrinane(1)was a potent anti-diabetic agent.Thirty-five tricyclic matrinic derivatives were synthesized and determined for their stimulatory effects on glucose consumption in L6 myotubes,taking 1 as the lead.In high-fat diet(HFD)and STZ induced diabetic mice,9a significantly lowers blood glucose,improves glucose tolerance,and especially alleviates diabetic nephropathy and islet damage.Mechanism study indicates that 9a simultaneously targets mitochondrial complex I to increase AMP/ATP ratio,as well as liver kinase B1(LKB1)and calcium/calmodulindependent protein kinase(Ca MKK),which synergistically activates AMPKαand then stimulates glucose transporter 4(GLUT4)membrane translocation and 2-deoxyglucose(2-DG)uptake to exert anti-diabetic efficacy.Therefore,compound 9a with a novel structure is a promising anti-diabetic candidate with the advantage of multiple-target mechanism,worthy of further investigation.

植物磷脂酸的特性及其在ABA诱导气孔运动中的作用

磷脂酸(PA)是应答多种生理过程的第二信使,其作为一个脂质信号快速积累从而响应多种环境。PA主要通过磷脂酶D (PLD)和磷脂酶C/甘油二酯激酶(PLC/DGK)途径产生。基于PLDs的生化特性、激活机制以及在不同类型胁迫下被激活的特定同种型的差异,不同类型胁迫下会产生特定分子种组成的PA。PA在多种环境下起信号转导作用,在调节气孔运动中,PA的作用模式主要是通过与多种蛋白结合,激活或抑制这些蛋白的活性,进而执行其信使功能。该文主要综述PA的生化特性以及信号途径中PA互作蛋白的研究进展,并提出PA研究中亟待解决的问题及今后的重点研究方向。