椴树阔叶红松林群落主要树种径级结构研究

椴树阔叶红松林群落主要树种径级结构研究孙伟中代力民章一平（中国科学院沈阳应用生态研究所,１１００１５）ＳｔｕｄｙｏｆＤｉａｍｅｔｅｒＢｒｅａｓｔＨｉｇｈＳｔｒｕｃｔｕｒｅｏｆｔｈｅＭａｉｎＴｒｅｅｓｉｎＴｉｌｉａＢｒｏａｄｌｅａｖｅｄＫｏｒｅａｎＰ...     

林下人参生理特性和生长与林内生态因子的关系

结合模拟试验,对林下人参的生理活动及生长过程与林内生态因子的关系进行 了观测研究．结果表明,林内光照、水分、温度等因子与林下人参生长的关系极为密切．一 般林内光照在中等条件下,即相对光照在１０～３５％左右．林分郁闭度约０．６～０．８,土壤含 水量在 ３５～４０％时人参生长最好;林下人参的物候进程及生长与温度的关系密切．林内 温度在５℃左右人参芽胞开始萌动,１５℃左右地上茎高生长进入速生期,６月上旬生长停 止．因此,人为调节各种生态因子在适宜的范围内有利于林下人参的生长．     

碱性磷酸酶标A蛋白加强的PAP技术

本文介绍一种碱性磷酸酶标Ａ蛋白加强的ＰＡＰ技术。采用ＰＡＰ技术、碱性磷酸酶标Ａ蛋白（ＰＡＡＰ）技术ＰＡＡＰ和加强的ＰＡＰ（ＰＡＰ－ＰＡＡＰ）技术显示下丘脑室旁核催产素（ＯＴ）能神经元。结果发现,其中使用ＰＡＰ－ＰＡＡＰ技术免疫反应产物的显色最深。此技术的原理可能是,由于Ａ蛋白分子至少有四个位点能与ＩｇＧ分子的Ｆｃ段高亲合性地结合,故在该技术中,先经过ＰＡＰ程序的三步免疫反应并显色后,每个与一抗结合的二抗分子上和每个与二抗结合的ＰＡＰ复合物分子上各暴露一个能与Ａ蛋白分子结合的Ｆｃ段,在随后经过ＰＡＡＰ技术处理时,部分ＰＡＡＰ复合物分子就结合在这些Ｆｃ段上,经显色后,ＰＡＡＰ技术显示的浅紫兰色与ＰＡＰ技术显示的浅棕褐色重叠,变成更深的反差明显的深棕褐色。     

类胡萝卜素产生菌深红酵母(Rhodotorula rubra)的培养条件的优化研究

本文研究深红酵母及其产生的类胡萝卜素的培养优化条件,并对其进行了小型发酵试验,结果表明pH值对深红酵母和类胡萝卜素有影响,初始pH值越低,色素的积累量越高,发酵过程中控制pH值能有效地增加色素积累的速度和初始色素积累量,但随着发酵时间的延长,色素积累量逐渐下降。     

Sugar induced cell death in yeast is dependent on the rate of sugar phosphorylation as determined by Arabidopsis thaliana hexokinase

Sugars like glucose and fructose induce death of yeast cells within a few hours, in the absence of additional nutrients to support growth, while cells incubated in water remain viable for weeks. This sugar-induced cell death (SICD) by glucose and fructose required glucose or fructose phosphorylation since yeast cells deficient in hexose phosphorylation did not die. However, when hexose phosphorylation is restored by complementation with Arabidopsis thaliana hexokinase, the cells died. The affinity of A. thaliana hexokinase is about 400 times higher for glucose than for fructose, therefore, A. thaliana hexokinase was further utilized to study the role of hexose phosphorylation in SICD. The rate of SICD of hexokinase-deficient yeast cells expressing A. thaliana hexokinase was significantly slower in fructose than in glucose, indicating that SICD is determined by the rate of hexose phosphorylation. The significance of hexose phosphorylation and its role in SICD is discussed.     

Seedling establishment of deciduous trees in various topographic positions

Abstract. We investigated the effect of topography‐related environmental factors (i.e., ground‐surface stability and soil moisture) on seedling establishment of 8 deciduous tree species. A field experiment was carried out using canopy species, which were classified into 3 groups based on the spatial distribution of adult trees (ridge, slope and valley). Demographic parameters were compared among species during the early stage of seedling establishment among 3 topographic positions in combination with gap and canopy conditions. The percentage of emerging seedlings tended to be lower on the ridge irrespective of the adult topographical distribution patterns. There was no clear trend in seedling emergence among the species groups classified by their spatial distribution. Seedling survival during 2 growing seasons was significantly different among species, topographic positions and light conditions. On the ridge, seedlings of the species dominating ridge tops had greater survival than those of other species, probably due to differences in demand for soil moisture. On the slope, frequent physical damage caused by surface material movement was observed and some species showed greater adaptability to the disturbed slope habitat. Survival of all seedlings was highest in the valley plots. Light conditions were the critical factor for seedling survival in some species. The results of this study suggest that topography creates diverse habitats for the establishment of tree seedlings. In addition to soil moisture, surface material movement may be a significant factor affecting seedling establishment.     

LncRNA SNHG12 promotes tumorigenesis and metastasis in osteosarcoma by upregulating Notch2 by sponging miR-195-5p

Osteosarcoma is the most common primary malignant bone tumor and has a high fatality rate in children and adolescents. Recently, an increasing amount of evidence has demonstrated that lncRNAs have crucial roles in regulating biological characteristics in malignant tumors. Therefore, this research was carried out to uncover the biological function and the potential molecular mechanism of SNHG12 in osteosarcoma. In this study, we found that SNHG12 was significantly upregulated in both osteosarcoma tissues and cell lines and osteosarcoma patients with high levels of SNHG12 tended to have a poor prognosis. We evaluated the biological function of SNHG12 in 143B and U2OS cells and show that the downregulation of SNHG12 suppressed cell proliferation by blocking cell cycle progression at the G0/G1 phase and weakened cell invasion and migration abilities. Dual-luciferase reporter and RIP assays were conducted to confirm that SNHG12 functioned as a ceRNA, modulating the expression of Notch2 by sponging miR-195-5p in osteosarcoma. We further demonstrate that Notch2 played a crucial role in activating the Notch signaling pathway. In conclusion, SNHG12 might serve as a valuable biomarker and prognosis factor in osteosarcoma patients. The SNHG12/miR-195-5p/Notch2-Notch signaling pathway axis might become a novel therapeutic for osteosarcoma.     

GBP3 promotes glioma cell proliferation via SQSTM1/p62-ERK1/2 axis

Guanylate binding proteins (GBPs) are interferon-inducible large GTPases and play a crucial role in cell-autonomous immunity. However, the biology function of GBPs in cancer remains elusive. GBP3 is specifically expressed in adult brain. Here we show that GBP3 is highly elevated in human glioma tumors and glioma cell lines. Overexpression of GBP3 dramatically increased glioma cell proliferation whereas silencing GBP3 by RNA interference produced opposite effects. We further showed that GBP3 expression was able to induce sequestosome-1(SQSTM1, also named p62) expression and activate extracellular signal-regulated kinase (ERK1/2). The SQSTM1-ERK1/2 signaling cascade was essential for GBP3-promoted cell growth because depletion of SQSTM1 markedly reduced the phosphorylated ERK1/2 levels and GBP3-mediated cell growth, and inhibition of mitogen-activated protein kinase/ERK kinase abolished GBP3-induced glioma cell proliferation. Consistently, GBP3 overexpression significantly promoted glioma tumor growth in vivo and its expression was inversely correlated with the survival rate of glioma patients. Taken together, these results for the first time suggest that GBP3 contributes to the proliferation of glioma cells via regulating SQSTM1-ERK1/2 pathway, and GBP3 might represent as a new potential therapeutic target against glioma.