Seed Priming with Gibberellin Regulates the Germination of Cotton Seeds Under Low-Temperature Conditions

Journal of Plant Growth Regulation - Exogenous substances play an important role in the response of cotton to low-temperature conditions during the germination stage, but little is known about the...     

谷子不育系及其相应可育系小孢子发育的细胞学观察

以谷子2个品种的不育系及其保持系为材料,对其小孢子发育的细胞形态学进行了观察研究。结果表明:昭盟A花药的外部形态及花粉母细胞的发育过程与昭盟B相似,能形成外观正常的三核花粉,但其花药不能开裂散粉。石炮A表现出了败育时间和方式的多样性,且不育系与保持系间在花药长度上有显著差异。此外,两种不育系的维管束都表现出不同程度的发育不良。不良程度与药囊退化程度相关。     

Phytoconstituents of Selaginella effusa Alston and Their α-Glucosidase as well as Urease Inhibitory Activities

Three new compounds ( 1 – 2 , 14 ), as well as 22 known compounds ( 3 – 13 , 15 – 25 ), were extracted for the first time from the Selaginella effusa Alston (S. effusa). For the unknown compounds, the planar configurations were determined via NMR and by high-resolution mass spectrometry, while their absolute configurations were determined by calculated electronic circular dichroism (ECD), and the configuration of the stereogenic center of biflavones 4 – 5 were established for the first time. The pure compounds ( 1 – 25 ) were tested in vitro to determine the inhibitory activity of the enzyme-catalyzed reactions. Compounds 1 – 9 inhibited α-glucosidase with IC₅₀ values ranging from 0.30±0.02 to 4.65±0.04 μM and kinetic analysis of enzyme inhibition indicated that biflavones 1 – 3 were mixed-type α-glucosidase inhibitors. Compounds 12 – 13 showed excellent inhibitory activity against urease, with compound 12 (IC₅₀=4.38±0.31 μM) showing better inhibitory activity than the positive control drug AHA (IC₅₀13.52±0.61 μM). In addition, molecular docking techniques were used to simulate inhibitor-enzyme binding and to estimate the binding posture of the α-glucosidase and urease catalytic sites.     

Dampening HOTAIR sensitizes the gastric cancer cells to oxaliplatin through miR-195-5p and ABCG2 pathway

Long non-coding RNAs (lncRNA) have an extensive role in the progression and chemoresistance of gastric cancer (GC). Deeply study the regulatory role of lncRNAs could provide potential therapeutic targets. The aim of this study is to explore the regulatory role of HOTAIR in the progression and oxaliplatin resistance of GC. The expression of HOTAIR in GC and cell lines were detected by using qRT-PCR. Cell proliferation and apoptosis were analysed by CCK-8, EdU incorporation and flow cytometry. Luciferase reporter assay was used to identify the interaction between HOTAIR and ABCG2 (ATP-binding cassette (ABC) superfamily G member 2, ABCG2) via miR-195-5p. The regulatory functions were verified by using molecular biology experiments. HOTAIR was significantly overexpressed in GC and associated with poor prognosis. Knock-down of HOTAIR inhibited the GC cells proliferation and oxaliplatin resistance, while overexpression of HOTAIR showed opposite functions. Further studies found that HOTAIR acted as a competing endogenous RNA (ceRNA) to absorb miR-195-5p and elevated the expression of ABCG2, which leads to resistance of GC cells to oxaliplatin. Taken together, our findings demonstrated that HOTAIR regulates ABCG2 induced resistance of GC to oxaliplatin through miR-195-5p signalling and illustrate the great potential of developing new therapeutic targets for GC patients.     

ent-Pimarane Diterpenes from the Aerial Parts of Siegesbeckia pubescens

Five new ent-pimarane diterpenes ( 1 – 5 ) and five known analogs ( 6 – 10 ) were isolated from the aerial parts of Siegesbeckia pubescens. Their structures, including absolute configurations, were determined by comprehensive spectroscopic methods especially 1D and 2D NMR and quantum chemical electronic circular dichroism calculations. All the isolated compounds were evaluated for their cytotoxicity against human BT549, A549 and H157 cancer cell lines. Among them, compounds 1 and 2 showed mild cytotoxicity against lung cancer cell lines H157 with IC₅₀ values of 16.35±2.59 and 18.86±4.83 μM, respectively.     

Floral scent emission is the highest at the second night of anthesis in Lonicera japonica (Caprifoliaceae)

Floral color change in diverse plants has been thought to be a visual signal reflecting changes in floral rewards, promoting pollinator foraging efficiency as well as plant reproductive success. It remains unclear whether olfactory signals co-vary with floral color change. We investigated the production rhythms of floral scent and nectar associated with floral color change in Lonicera japonica. The flowers generally last 2–3 days. They are white on opening at night (N1) and become light yellow the following day (D1), yellow on the second night (N2), and golden on the second day of flowering (D2). Our measurements in the four stages indicated that nectar production decreased significantly from N1 and D1 to N2 and D2, tracking the floral color change. A total of 34 compounds were detected in floral scent and total scent emission was significantly higher in N2 than in the other three stages. The scent emission of three major compounds, Linalool, cis-3-Hexenyl tiglate, and Germacrene D was also significantly higher in N2, but the relative content of Linalool decreased gradually, cis-3-Hexenyl tiglate increased gradually, and the relative content of Germacrene D did not differ among the four measured stages. Greater scent emission by night than by day suggested a strong olfactory signal to attract nocturnal hawkmoths, the effective pollinators. However, floral scent rhythms in the four stages did not match the color change and nectar secretion, suggesting that floral color (visual) and scent (olfactory) in this species may play different roles in attracting or filtering various visitors.     

Critical roles of non-coding RNAs in lifecycle and biology of Marek’s disease herpesvirus

Science China Life Sciences - Over the past two decades, numerous non-coding RNAs (ncRNAs) have been identified in different biological systems including virology, especially in large DNA viruses...     

Expression of p21ras-related protein in the plasma and tissue of patients with adenomas and carcinomas of the colon

Over-expression of p21 ras-related protein was determined in the plasma by immunoblotting and in the tissue by immuno-histochemistry in a cohort of patients undergoing colonoscopy. In the plasma samples, p21 ras over-expression was detected in: 9% (4/47) of normal controls; 21% (13/61) of individuals with normal colonoscopies but with a prior history of colonic neoplasia; 12% (4/33) of small adenoma patients, 29% (6/21) of large adenoma patients; 63% (5/8) of carcinoma-in-adenoma patients; 50% (2/4) of Dukes' A carcinoma patients; and 20% (2/10) of Dukes' B-D carcinoma patients. In the tissue samples, p21 ras over-expression was detected in: 25% (2/8) of small adenoma patients; 44% (4/9) of large adenoma patients; 100% (4/4) of carcinoma-in-adenoma patients; and 33% (1/3) of Dukes' B-C carcinoma patients. For matched plasma-tissue pairs, there was a statistically significant correlation for p21 ras over-expression (R = 0.47, p = 0.02).     

云南松半同胞家系初期子代测定

对收集的云南松（Ｐｉｎｕｓ　ｙｕｎｎａｎｅｎｓｉｓ）２９２个半同胞家系进行栽培试验,经方差分析知各家系子代间高生长有极显著差异,真正的优树占参试总数的２９．７％（广西）;树高广义遗传力为５８．０％,遗传增益为３８．８９％;同一林分内家系间高生长变异幅度小于林分之间的变异幅度。     

癫痫对大鼠学习记忆的影响及与生长抑素的相关性研究

对听源性癫痫大鼠进行迷宫训练,观察癫痫发作对大鼠光分辨学习作业的成绩以及用放射免疫分析法测定的大鼠部分脑区中生长抑素含量的影响。结果表明：（１）癫痫发作对大鼠记忆阶段有明显的抑制作用（Ｐ＜０．０１）;（２）癫痫发作后,在大鼠信息提取明显障碍的同时,其颞叶皮层、下丘脑、垂体及海马中生长抑素的含量明显增加（Ｐ＜０．０５－０．０１）。结果提示：癫痫发作影响大鼠学习记忆过程,在该过程中生长抑素含量发生改变。