白沙枇杷果实发育、果实水势及与裂果关系研究

对生长在山坡地6年生白沙枇杷(Eriobotrya japonica Lindl.)的裂果与果实发育、可溶性糖含量、土壤相对含水量及果实水势关系进行了研究,并探讨了覆盖地膜、断根和果实套袋技术对预防裂果的效果。结果表明,随着白沙枇杷果实的发育,果形指数变小;临近成熟期,果实的可溶性糖含量最高,土壤相对含水量增加,同时果实水势也升高。模拟大雨后,果实水势与裂果率呈正相关,相关系数R=0.941。这说明白沙枇杷临近成熟时,果实内积累了大量的可溶性糖等高渗透物质,从高含水量的土壤中大量吸收水分,使果实水势升高,导致裂果。以覆盖地膜、断根和果实套袋组合的技术预防裂果的效果最好,其中覆盖地膜和断根对预防裂果的贡献较大。     

REPORT OF A NEW INVASIVE ALGA IN THE ATLANTIC UNITED STATES: “HETEROSIPHONIA” JAPONICA IN RHODE ISLAND1

Recent collections of tetrasporangiate “Heterosiphonia” japonica Yendo from Watch Hill to Point Judith, Rhode Island, represent the first report of this nonnative alga in the western Atlantic. Native to the Pacific Ocean, this species was unintentionally introduced into European waters by 1984 and has subsequently invaded the eastern Atlantic Ocean widely from France to Norway and south into the Mediterranean Sea. Thus far, all western Atlantic collections of this species are confined to the outer coast of Rhode Island, and at present are not found in Narragansett Bay or in Long Island Sound along the Connecticut coast. Molecular and morphological studies confirm the identity of this newly introduced invasive species.     

Hinokiresinol is not a precursor of agatharesinol in the norlignan biosynthetic pathway in Japanese cedar

The biosynthetic relationship between the two norlignans agatharesinol and trans-hinokiresinol was investigated. Fresh sapwood sticks of Cryptomeria japonica were fed with stable isotope-labeled compounds, namely p-coumaryl alcohol-[9,9-²H], p-coumaryl alcohol-[9-¹⁸O] and trans-hinokiresinol-[1-²H], and then incubated under high-humidity for approximately 20 days, during which the two norlignans were produced simultaneously. While trans-hinokiresinol was strongly deuterium-labeled after feeding with p-coumaryl alcohol-[9,9-²H], agatharesinol was only lightly labeled after feeding with either p-coumaryl alcohol-[9,9-²H] or -[9-¹⁸O]. These results suggest that p-coumaryl alcohol, which is a precursor of hinokiresinol, is not involved in the biosynthesis of agatharesinol. Therefore, the norlignan carbon skeleton of agatharesinol must be framed from different types of phenylpropanoid monomers compared to those utilized by the trans-hinokiresinol pathway. The biosynthesis of these two norlignans seems to branch at an early stage, i.e., before the framing of the norlignan carbon skeleton. Furthermore, agatharesinol was not labeled with deuterium after feeding with ²H-labeled trans-hinokiresinol, which has the simplest norlignan structure. This result strongly supports the suggestion that the conversion of trans-hinokiresinol to agatharesinol is not part of the biosynthesis of norlignans and that early branching occurs instead.     

东亚三角涡虫Rab蛋白cDNA序列的克隆与生物信息学分析

通过构建东亚三角涡虫(Dujesia japonica)cDNA文库,随机挑选重组阳性克隆进行测序,对部分序列进行引物步移法测序,获得1个三角涡虫新基因——Rab蛋白基因(DjR),涡虫Rab蛋白cDNA全长2 141 bp,开放性阅读框(ORF)621bp,编码206个氨基酸,相对分子量为23.1 kD,等电点6.59,属亲水性蛋白,主要定位于细胞质中,在氨基酸第20和21位之间有信号肽剪切位点。有8个磷酸化位点。含有小G蛋白家族5个保守的鸟苷酸结合区域。同源性比较分析结果表明,其碱基序列与已经报道的其他23个物种的相似性为53%-90%,且符合种属之间的进化关系。     

日本七鳃鳗富含半胱氨酸RGD蛋白Lj-RGD1抑制血小板聚集及抗血管新生功能

Lj-RGD1来源于日本七鳃鳗口腔腺,富含半胱氨酸并具有RGD(Arg-Gly-Asp)模体.为了验证Lj-RGD1是否具有抑制血小板聚集、抗血管新生等去整合素样典型功能,本文对七鳃鳗Lj-RGD1进行了克隆表达及活性测定.提取七鳃鳗口腔腺中总RNA进行RT-PCR扩增,获得Lj-RGD1的420 bp cDNA.对其进行克隆、表达及组氨酸亲和层析纯化后,获得分子量为169 kD的可溶性蛋白rLj-RGD1.活性测定结果显示,rLj-RGD1呈剂量依赖方式抑制ADP诱导的兔血小板聚集,IC50为123 μmol/L;血管新生抑制实验结果表明,rLj-RGD1能够诱导ECV304细胞凋亡,抑制ECV304细胞增殖和管状物形成,并呈剂量依赖性方式抑制鸡胚胎绒毛尿囊膜（chorioallantoic membrane,CAM）血管新生.由此可见,Lj-RGD1具有去整合素样生物活性,在血栓或血管异常新生类疾病治疗中具有应用前景.     

The response of the early developmental stages of Laminaria japonica to enhanced ultraviolet-B radiation

The responses of the early development of Laminaria japonica collected from Kiaochow Bay in China to enhanced ultraviolet-B radiation (UV-B, 280—320 nm) were studied in the laboratory. The low UV-B ra-diations (11.7—23.4 J·m-2·d-1) had no significant effects on zoospores attachment, but when the UV-B dose > 35.1 J·m-2·d-1 the attachment decreased significantly compared with the control. Germination of embryospores was >93% under the low (11.7—35.1 J·m-2·d-1) doses, and in the range of 78.5%—88.5% under the high (46.8—70.2 J·m-2·d-1) UV-B doses, indicating a significant radiation effect. Under the higher UV-B exposure (35.1—70.2 J·m-2·d-1), all of the few gametophytes formed from embryospores died 120 h post-release. After exposure to the low UV-B radiation (11.7—23.4 J·m-2·d-1), the formation of sporophytes decreased and the female gametophyte clones increased compared with the control. However, the sex ratio and the relative growth of female gametophytes/sporophytes had not signifi-cantly changed. According to the results, enhanced UV-B radiation has a significant effect on the early development of L. japonica under laboratory conditions, suggesting that the UV-B radiation could not be overlooked as one of the important environmental factors influencing the ontogeny of macroalgae living in marine ecosystems.     

Anti-inflammatory activities of triterpenoid saponins from Polygala japonica

Bioassay-guided investigation was performed to identify the active constituents from a methanol extract of Polygala japonica, a folk medicinal plant widely used in China to treat inflammatory diseases. The n-BuOH and EtOAc fractions of the P. japonica methanol extract, which show significant anti-inflammatory activity in in vivo test, were further subjected to column chromatography to afford six triterpene glycosides, marked here as saponins 1–6. All compounds were evaluated for their anti-inflammatory activity in the carageenan-induced mouse paw edema test, and saponins 1, 4 and 5 showed significantly anti-inflammatory effects on both phases of carageenan-induced acute paw edema in mice. Saponin 5 was also found to significantly inhibit the production of inflammatory mediators – nitric oxide (NO) in LPS-stimulated RAW264.7 macrophages, with no obvious effects on macrophage viability.     

Two New Diterpenoid Alkaloids from Spiraea japonica L. f. var.fortunei （Planchon） Rehd.

Two new hetisine-type C20-diterpenoid alkaloids named spiraqine (1) and 6-hydroxylspiraqine (2), and four known alkaloids, namely spiredine (3), spiradine A (4), spiradine B (5), and spirasine V/VI (6),were isolated from Spiraea japonica L. f. var.fortunei (Planchon) Rehd. The structures of the alkaloids were elucidated using nuclear magnetic resonance analysis (1H-NMR, ^13C-NMR, DEPT, HMQC, and HMBC) and mass spectrometry data.     

土壤养分对蝴蝶花的花形态可塑性的影响

为了研究土壤养分对蝴蝶花的花形态可塑性的影响,在田间实验中对蝴蝶花进行了高、中、低养分（N、P、K）水平处理。实验表明,随着土壤养分水平的增加,外轮花瓣长和宽、内轮花瓣长和宽、雌蕊长、雄蕊长、花冠直径均逐渐增加。花各组成部分的形态大小间相关性显著（P=0．05）。结合花部形态特征对环境异质性的生态适应意义,对实验结果进行了讨论。