羊草细胞差异表达基因分析与遗传转化方法研究

羊草（Leymus chinensis (Trin.) Tzvel），隶属禾本科赖草属，是欧亚大陆草原区东部重要建群种之一。羊草是牧草之王，是我国比较有优势的战略性生物资源，对我国北方畜牧业的发展以及生态环境的保育均具有重要意义。近年来，由于缺乏科学管理、过度放牧等不利影响，加之羊草本身固有的“三低”问题（即抽穗率低、结实率低、发芽率低）已对羊草生物多样性维持构成了严重的威胁，限制了我国人工草地建设和天然草地的改良及沙化治理的步伐。因此，如何通过细胞、分子生物学以及生物技术手段改良羊草、快速评价和创造新的种质;如何加快育种进程便成为当前亟待解决的问题。本文围绕这些问题开展了系统的研究并取得如下结果： 1. 建立了羊草离体培养再生体系，并研究了影响愈伤组织诱导和植株再生的因素，影响植株再生的主要因素为激素配比和基因型。将3～5mm的幼穗接种到含有2,4-D 0～5.0mg/L的N6基本培养基上，随着2,4-D浓度的变化，愈伤组织诱导率不同，最高诱导率为93.21%（基因型C6）、最低为33.35%（吉生1号）;愈伤组织在N6(大)＋B5(微)＋KT1.0mg/L+BA1.0mg/L的培养基上可以分化出芽，并在1/2MS培养基上生根。羊草基因型W4不同幼穗诱导的愈伤组织在继代培养过程中其生长、褐化死亡等方面存在着差异;在分化培养过程中，不同幼穗的愈伤组织最高分化率为9.24%，最低分化率为5.26%。 2. 对来自同一基因型不同幼穗的愈伤组织中差异表达的基因进行了研究。采用DDRT-PCR技术对其差异表达的基因进行了分离，通过银染技术显示差异片段。将得到的差异片段进行回收、克隆测序，得到两个差异片段序列，经过序列分析表明，其中一个片段是与水稻翻译延伸因子eEF-1基因高度同源;另一差异片段与水稻谷胱甘肽转移酶GST基因高度同源。 3. 建立了羊草遗传转化方法。在获得羊草离体培养再生体系的基础上，采用基因枪法对羊草两个基因型进行转抗除草剂基因（PAT）的研究。对分别来自基因型W4和C3的愈伤组织各1430和1850块进行转化。在附加1.0mg/L PPT的培养基上进行一系列的筛选培养，共获得了23株再生苗，经过生根筛选培养，得到5株抗性苗，3株来自基因型W4，2株来自基因型C3。对5株植株进行PCR和Southern 检测，得到2株阳性苗，均来自基因型W4，对阳性植株经过无性繁殖得到的无性系进行PCR检测及Basta耐受性鉴定，外源基因可以在其无性系稳定遗传并表达，无性系除对Basta具有抗性外，其表型特征与对照无明显区别。

Purif ication and Characterization of Jerdonitin ,a Non2hemorrhagic Metalloproteinase fromTrimeresurus jerdonii Venom

以前从菜花烙铁头蛇毒中分离纯化到J erdonitin 。与其他Ⅱ型蛇毒金属蛋白酶相比, J erdonitin 由金属蛋白酶和去整合素两个结构域组成。但没有检测到其出血和纤维蛋白原降解活性, 推测可能高压液相色谱的有机溶液影响了其酶活性。采用不含高压液相色谱柱层析的新分离手段分离得到J erdonitin 。J erdonitin 在还原和非还原SDS2PAGE 电泳中分别呈现一条表观分子量为38 和36 kDa 的条带。像其他典型的蛇毒金属蛋白酶一样, J erdonitin 优先降解人纤维蛋白原的alpha 链, 并且该活性能被EDTA 完全抑制, 而PMSF 对其没有影响。J er2 donitin 不诱导小白鼠皮下出血。

巴氯芬对慢性吗啡依赖后条件化位置偏好和戒断症状的抑制

小鼠连续7天腹腔注射吗啡(40mg/kg)建立条件化位置偏好模型,连续皮下递增注射吗啡(25、50、75、100、125、150mg/kg),成瘾后腹腔注射纳络酮(6mg/kg)诱导戒断症状(跳跃行为)建立戒断模型.腹腔注射GABAB受体激动剂巴氯芬(2 mg/kg)可以有效地抑制吗啡诱导的条件化位置偏好和减轻纳络酮诱导的戒断症状,结果表明GABA系统参与动物成瘾后渴求和戒断过程,激动GABAB受体可以在一定程度上抑制成瘾的心理和生理戒断症状.

MANDIBULAR MORPHOMETRICS AMONG MACAQUES - THE CASE OF MACACCA-THIBETANA

Recent field studies suggest that Macaca thibetana, a large endemic Chinese macaque, may be quite folivorous, distinguishing it from most other macaque species, which tend to be primarily frugivorous. To understand how this diet affects its masticatory system, we conducted a comparative morphometric study of mandibular dimensions. We took linear measurements from male and female mandibles of this species as well as four other macaques-M. fascicularis, M. nemestrina, M. arctoides, and M. assamensis-and four species of Presbytis-P. obscura, P. rubicunda, P. cristata, and P. phayrei-and subjected to them to a variety of analyses. Based on analyses of variances and discriminant analyses on each sex individually, the mandible of M. thibetana corresponds to expected patterns for folivorous primates with respect to its wide condyles and thick corpora: However, the height of the corpus and symphysis are lower, and the anteroposterior length of the condyle is longer than predicted for a folivore. In addition to interpretations specifically relating to M. thibetana, we also discuss the functional morphology of the other species in light of what is published about their diets.

海洋喇叭虫rRNA基因18S -ITS1序列及其系统发育分析(英文)

海洋喇叭虫Maristentordinoferus 1996年在关岛(Guam)的珊瑚暗礁上被发现 ,至今尚未阐明其确切的系统发育地位。克隆到的海洋喇叭虫的 18S ITS1 5 8SrDNA序列包括 2 2 2bp的 18S序列 ,77bp的ITS1序列和 2 2bp的 5 8S序列。比较分析了纤毛虫主要类群的ITS1序列后得出 :短的ITS1序列可能是异毛类纤毛虫的特征。根据 18S序列 ,利用邻接法构建 ,最大简约法和最大似然法构建系统发育树。其拓扑结构显示海洋喇叭虫属于异毛纲纤毛虫 ,但并不隶属喇

Geostatistical analysis of chlorophyll a in freshwater ecosystems

Horizontal spatial patterns of chlorophyll a in Meiziya Reservoir, Hubei Province, China were analyzed once each month during May, June and July 1997. Two geostatistical techniques, semivariance and fractal analysis, were used to determine variation in chlorophyll a over the whole study area (isotropic) and in different directions (anisotropic). Both techniques provided useful information for detecting and assessing spatial pattern changes of chlorophyll a in freshwater environments. Based on our case study, the distribution of chlorophyll a shifted from aggregated to random distribution in the case of small rainfall event, and then returned to the aggregated distribution after a large rainfall event. On the other hand, the distribution of chlorophyll a became more heterogeneous or random in the direction of water flow (S-N direction) when rainfall events occurred, which was enhanced by rainfall intensity. In contrast, the influence of water flow on the spatial patterns was weak in the E-W direction, and thus the distribution of chlorophyll a remained aggregate with a moderate spatial heterogeneity.

Genome mapping in aquatic animals: Progress and future perspectives

The genome of aquatic animals is poorly understood and information from different taxonomic groups is sketchy. While there have been intensive genomic studies on some fish models, investigations on other fishes and invertebrates have been scarce. Yet there are recently some coordinated studies on genome mapping in a number of aquaculture animals of economic importance. This review summarizes information available on genome mapping of the important fish models and aquaculture animals. The future perspectives of this field of studies are discussed.

Thermo-optical switch matrix based on silicon-on-insulator waveguides

A thermo-optical waveguide switch matrix is designed and fabricated on silicon-on-insulator wafer. Multi-mode interferometers are used as power splitters and combiners in a Mach-Zehnder structure. Inductively coupled plasma reactive ion etching is used to fabricate the waveguides. The rise and fall times of the switch matrix are 13 mu s and 7 mu s, respectively. Switch cells have an average switching power consumption of 340 mW.

Hydrogen-dependent lattice dilation in GaN

Using Raman spectroscopy we have analysed the strain status of GaN films grown on sapphire substrates by NH3 source molecular beam epitaxy (MBE). In addition to the expected compressive biaxial strain, in some cases GaN films grown on c-face sapphire substrates suffer from serious tensile biaxial strain. This anomalous behaviour has been well interpreted in terms of interstitial hydrogen-dependent lattice dilation. The hydrogen concentration in the films is measured by nuclear reaction analysis (NRA). With increasing hydrogen incorporation, the residual compressive biaxial strain is first further relaxed, and then turns into tensile strain when the hydrogen contaminant exceeds a critical concentration. The hydrogen incorporation during the growth process is found to be growth-rate dependent, and is supposed to be strain driven. We believe that the strain-induced interstitial incorporation is another way for strain relaxation during heteroepitaxy, besides the two currently well known mechanisms: formation of dislocations and growth front roughening.