Investigation and Analysis of Impact from High Frost on Vascular Plants in the Kunming Botanical Garden

High frost, a common natural disaster, means heavy damage to plants with temperature dropped below 0℃. In mid December 2013, Kunming suffered from severe frosts, resulting in large area damage of the plants, which brought huge losses. To provide a reference for scientifically and reasonably preventing and reducing frost freezing to garden plants, it is necessary to understand resistance of various plant catagories to extreme cold hazards. In this paper, a sample survey on 225 plant species from 90 families was performed for victimized plants in Kunming Botanical Garden. With the statistical analysis of the relationship between damage degree and plant systematics, morphology, distribution or other factors, we drew several conclusions. For example, ferns had a relatively poor frost resistance while gymnosperms mostly were strong, and angiosperms showed larger differences in frost resistance; annual herbaceous and evergreen woody had a stronger resistance than perennial herbaceous and deciduous woody respectively; native species exhibited greater resistance than introduced species. According to the results, some suggestions were given for protecting existing garden plants and constructing new landscapings. That is based on the strength of frost resistance of different plants, on one hand to give the garden plants a positive and effective protection and prevention measures against frost damage, on the other hand to select species suitable for planting combined environmental conditions with characters of plants.     

A Proteomic Analysis of Placental Trophoblastic Cells in Preeclampsia–Eclampsia

To explore the proteomic changes of placental trophoblastic cells in preeclampsia–eclampsia (PE), placental trophoblastic cells from normally pregnant women and women with hypertension during gestational period were prepared by laser capture microdissection (LCM), and proteins isolated from these cells were subjected to labeling and proteolysis with isotope-coded affinity tag reagent. A qualitative and quantitative analysis of the proteome expression of placental trophoblastic cells was made using two-dimensional liquid chromatography tandem mass spectrometry (2D LC–MS/MS). A total of 831 proteins in placental trophoblastic cells were identified by combined use of LCM technique and 2D LC–MS/MS. The result was superior to that of conventional two-dimensional electrophoresis method. There were marked differences in 169 proteins of placental trophoblastic cells between normally pregnant women and women with PE. Of 70 (41.4 %) proteins with more than twofold differences, 31 proteins were down-regulated, and 39 were up-regulated in placental trophoblastic cells of the woman with PE. Laminin expression in placenta trophoblastic cells of women with PE was significantly down-regulated as confirmed by Western blot analysis. These findings provide insights into the proteomic changes in placental trophoblastic cells in response to PE and may identify novel protein targets associated with the pathogenesis of PE.     

银杏胚珠贮粉室的早期发育

对银杏 (GinkgobilobaL .)胚珠贮粉室的早期发育过程以及珠心细胞死亡的细胞学机制进行了研究。DNA电泳出现DNAladder和TUNEL标记说明参与形成贮粉室的珠心细胞死亡是程序性死亡 (PCD)过程 ,并且显示出在贮粉室形成中 ,PCD的发生有一定的空间分布式样。结合扫描电镜观察 ,贮粉室的早期发育可分为 4个阶段 :起始事件是位于珠孔端的 3至 4层珠心细胞纵向伸长 ;接着 ,位于珠心组织最上部 (珠孔端 )的珠心细胞启始死亡 ;然后 ,这些已经纵向伸长的珠心细胞向基地和侧向地逐渐死亡 ,形成一个空腔 ;最后 ,珠孔端珠心表皮细胞以开裂的方式与其余表皮细胞脱离而形成贮粉室的开口。大孢子母细胞时期 ,贮粉室尚未发生 ;四分体阶段 ,贮粉室已经开始形成 ;到雌配子体发育时期 ,贮粉室已经完全产生。反映大孢子发育和贮粉室发生的同步性。     

Akt, a Target of Phosphatidylinositol 3-Kinase, Inhibits Apoptosis in a Differentiating Neuronal Cell Line

Phosphatidylinositol (PI) 3-kinase has been suggested to mediate cell survival. Consistent with this possibility, apoptosis of conditionally (simian virus 40 T^ts) immortalized rat hippocampal H19-7 neuronal cells was increased in response to wortmannin, an inhibitor of PI 3-kinase. Downstream effectors of PI 3-kinase include Rac1, protein kinase C, and the serine-threonine kinase Akt (protein kinase B). Here, we show that activation of Akt is one mechanism by which PI 3-kinase can mediate survival of H19-7 cells during serum deprivation or differentiation. While ectopic expression of wild-type Akt (c-Akt) does not significantly enhance survival in H19-7 cells, expression of activated forms of Akt (v-Akt or myristoylated Akt) results in enhanced survival which can be comparable to that conferred by Bcl-2. Conversely, expression of a dominant-negative mutant of Akt accelerates cell death upon serum deprivation or differentiation. Finally, the results indicate that Akt can transduce a survival signal for differentiating neuronal cells through a mechanism that is independent of induction of Bcl-2 or Bcl-x_L or inhibition of Jun kinase activity.     

Site-specific integration of the phage ΦCTX genome into the Pseudomonas aeruginosa chromosome: characterization of the functional integrase gene located close to and upstream of attP

The site-specific integration of the phage ?CTX genome, which carries the gene for a pore-forming cytotoxin, into the Pseudomonas aeruginosa chromosome was analysed. The 1,167 by integrase gene, int, located immediately upstream of the attachment site, attP, was characterized using plasmid constructs, harbouring the integration functions, and serving as an integration probe in both P. aeruginosa and Escherichia coli. The attP plasmids p1000/p400 in the presence of the int plasmid pIBH and attP-int plasmids pINT/pINTS can be stably integrated into the P. aeruginosa chromosome. Successful recombination between the attP plasmid p1000 and the attB plasmid p5.1, in the presence of the int plasmid pIBH in E. coli HB101 showed that the int gene is active in trans in E. coli. The int gene product was detected as a 43 kDa protein in E. coli maxicells harbouring pINT. Proposed integration arm regions downstream of attP are not necessary for the integration process. pINT and phage ?CTX could be integrated together into P. aeruginosa chromosomal DNA, yielding double integrates.     

扬子鳄纹状体AChE、SOMmRNA阳性神经元的分布

目的 观察扬子鳄纹状体内乙酰胆碱酯酶（acetylcholinesterase,AChE）和生长抑素信使核糖核酸（somatostatin messenger ribonucleic acid,SOMmRNA）阳性神经元的形态和分布.方法 采用亚铁氰化酮法和原位杂交法观察扬子鳄纹状体内AChE和SOMmRNA阳性神经元的分布和特征.结果 扬子鳄纹状体内有AChE和SOMmRNA阳性神经元分布,两种神经元均有大、中、小型细胞,以中、小型细胞为主,神经元胞体呈圆形、椭圆形、三角形、梭形和多角形.结论 扬子鳄纹状体内有AChE和SOMmRNA阳性神经元分布.     

RFLP mapping of QTLs for yield and related characters in rice (Oryza sativa L.)

Quantitative triat loci (QTLs) for yield and related traits in rice were mapped based on RFLP maps from two indica/indica F₂ populations, Tesanai 2/CB and Waiyin 2/CB. In Tesanai 2/CB, 14 intervals carrying QTLs for eight traits were detected, including 3 for grain weight per plant (GWT), 2 for number of panicles per plant (NP), 2 for number of grains per panicle (NG), 1 for total number of spikelets per panicle (TNS), 1 for spikelet fertility (SF), 3 for 1000-grain weight (TGWT), 1 for spikelet density (SD), and 1 for number of first branches per main panicle. The 3 QTLs for GWT were located on chromosomes 1, 2, and 4, with 1 in each chromosome. The additive effect of the single locus ranged from 2.0 g to 9.1 g. A major gene (np4) for NP was detected on chromosome 4 within the interval of RG143–RG214, about 4cM for RG143, and this locus explained 26.1% of the observed phenotypic variance for NP. The paternal allele of this locus was responsible for reduced panicles per plant (3 panicles per plant). In another population, Waiyin 2/CB, 12 intervals containing QTLs for six of the above-mentioned traits were detected, including 3 for GWT, 2 for each of NP, TNS, TGWT and SD, 1 for SF. Three QTLs for GWT were located on chromosome 1, 4, and 5, respectively. The additive effect of the single locus for GWT ranged from 6.7 g to 8.8 g, while the dominance effect was 1.7–11.5 g. QTL mapping in two populations with a common male parent is compared and discussed.