海南龙血树离体快速繁殖

以3月龄高约25cm的海南龙血树为基本材料,以茎节纵切块为外植体,在改良MS 6-BA2.0mg/L NAA0.1mg/L培养基中培养1个月后萌芽率为78.6%。萌芽在MS 6-BA1.5mg/L NAA0.2mg/L培养基中连续两次继代培养,2个月后芽增殖倍数为2.9。丛芽及单芽都在MS 6-BA1.0mg/L NAA0.2mg/L培养基中进行培养,1个月后丛芽的单芽增殖倍数为4.6,单芽增殖倍数为0.8。萌芽放入MS(改良) NAA0.2mg/L培养基中进行培养,生根率为100%,移栽成活率为100%。     

Cyclopeptide alkaloids from Zizyphus nummularia

In addition to the known alkaloid nummularine-B, two new peptide alkaloids nummularine-M and nummularine-N have been isolated from Zizyphus nummularia and their structures elucidated. Nummularine-M is a 14-membered cyclopeptide and belongs to the integerrinine type, whereas nummularine-N is a 13-membered cyclopeptide like nummularine-B.     

Hedgehog信号通路及其抑制剂在癌症中的研究进展

Hedgehog(HH)信号通路在胚胎发育和器官形成中发挥重要作用。当该通路中成员发生异常如patched(PTCH)发生缺失或突变,smoothened(SMO)发生突变,Gli异常扩增或者蛋白质稳定性增加等,都会导致该通路异常激活,并诱导如基底细胞癌、成神经管细胞瘤等癌症发生。因此阻断HH信号通路是应用于癌症治疗的一个有效手段。目前以HH信号通路不同成员为靶点已开发出多种HH信号通路小分子抑制剂,其中以HH信号通路上游成员为靶点的抑制剂最多。在今后的研究中,应该更加注重于以HH信号通路下游为靶点,开发更加有效的抗癌药物。     

Evaluation of vitamin D3 A-ring analogues as Hedgehog pathway inhibitors

A structure-activity relationship study focusing on the A-ring of vitamin D3 (VD3) was undertaken to elucidate its role in inhibiting the Hedgehog pathway and in mediating anti-cancer effects. Analogues resulting from simple functional group substitution at 3' position of VD3 were evaluated in a variety of biological assays to determine their ability to selectively inhibit Hh signaling. Moderately active Hh inhibitors that have insignificant binding affinity for VDR were identified; however, these compounds also activate the traditional VDR pathway, presumably due to metabolites produced in the cultured cells. Thus, further structural modifications to the VD3 scaffold are required to yield potent, selective Hh inhibitors.     

柬埔寨白蝶兰，中国兰科一新记录种

报道中国兰科白蝶兰属一新记录种——柬埔寨白蝶兰Pecteilis cambodiana (Gagnep.) Aver.,描述其特征并提供了彩色图片。凭证标本保存于福建农林大学林学院树木标本室(FJFC)。     

海南龙血树WD40转录因子基因DcWD40-1的克隆和表达分析

海南龙血树是国产血竭的主要基源植物,其血竭主要化学成分为类黄酮化合物。为进一步了解DcWD40-1在类黄酮生物合成中的潜在功能和作用机制,该研究根据海南龙血树转录组数据,利用RT-PCR技术在海南龙血树中克隆了一个WD40基因DcWD40-1,该基因全长1 550 bp,包含一个1 353 bp的开放阅读框,编码450个氨基酸,蛋白质分子量50.77 kD,理论等电点5.71。生物信息学分析显示,DcWD40-1属于WD40蛋白家族成员,具有5个保守的WD40结构域,和其他植物WD40蛋白同源性高,保守性强。利用Genome Walking方法分离了1 503 bp的DcWD40-1启动子序列,该区域具有典型真核生物启动子结构特征,并含有多个应答激素和胁迫的响应元件。表达分析显示,血竭诱导剂能够诱导Dc WD40-1的表达,DcWD40-1的变化与血竭形成及类黄酮积累正相关。此外,DcWD40-1也能对茉莉酸甲酯、细胞分裂素、油菜素内酯和UV-B处理做出积极响应。     

Nummularine-O,a cyclopeptide alkaloid from Zizyphus nummularia

In addition to the known peptide alkaloid jubanine-B, a new peptide alkaloid, nummularine-O, has been isolated from the stem bark of Zizyphus nummularia and their structures have been elucidated by chemical and spectroscopic methods.     

Sativanine-g,a cyclopeptide alkaloid from Zizyphus sativa

In addition to the already described peptide alkaloids from the bark of Zizyphus sativa, a new compound of this class, sativanine-G, has been isolated and its structure elucidated. This alkaloid contains a 13-membered ring system and belongs to the nummularine-C class.     

A 13-membered cyclopeptide alkaloid from Zizyphus sativa

From the bark of Zizyphus sativa a new type of 13-membered cyclopeptide alkaloid, sativanine-D (1) has been isolated. Its structure was proved mainly by mass spectrometry and chemical degradation.     

Shifted from Wnt to Hedgehog signaling pathways

Two papers in recent issue of Developmental Cell (Glise et al. 2005; Gorfinkiel et al. 2005) have shown that Shifted, a Drosophila ortholog of Wnt Inhibitory Factor (WIF), modulates the distribution of Hedgehog protein in the wing imaginal disc through a Wnt-independent mechanism.     

Proteinase inhibitors from Erythrina lysistemon seed

Four proteinase inhibitors (DE-1 to DE-4) were purified from E. lysistemon seed by chromatographic procedures involving Sephadex G-50, DEAE-cellulo     

Hedgehog signal transduction: from flies to vertebrates

The patterning and morphogenesis of multicellular organisms require a complex interplay of inductive signals which control proliferation, growth arrest, and differentiation of different cell types. A number of such signaling molecules have been identified in vertebrates and invertebrates. The molecular dissection of these pathways demonstrated that in vertebrates, mutations or abnormals function of these signaling pathways were often associated with developmental disorders and cancer formation. The Hedgehog (Hh) family of secreted proteins provides a perfect example of such signaling proteins. In the following review, we will not discuss in detail the role of Hh as a morphogen, but rather focus on its signal transduction pathway and its role in various human disorders.