Dermal β-catenin activity in response to epidermal Wnt ligands is required for fibroblast proliferation and hair follicle initiation

Dermal fibroblasts are required for structural integrity of the skin and for hair follicle development. Uniform Wnt signaling activity is present in dermal fibroblast precursors preceding hair follicle initiation, but the functional requirement of dermal Wnt signaling at early stages of skin differentiation and patterning remains largely uncharacterized. We show in mice that epidermal Wnt ligands are required for uniform dermal Wnt signaling/β-catenin activity and regulate fibroblast cell proliferation and initiation of hair follicle placodes. In the absence of dermal Wnt signaling/β-catenin activity, patterned upregulation of epidermal β-catenin activity and Edar expression are absent. Conversely, forced activation of β-catenin signaling leads to the formation of thickened dermis, enlarged epidermal placodes and dermal condensates that result in prematurely differentiated enlarged hair follicles. These data reveal functional roles for dermal Wnt signaling/β-catenin in fibroblast proliferation and in the epidermal hair follicle initiation program.     

Association between the G-protein β3 subunit C825T polymorphism with essential hypertension: a meta-analysis in Han Chinese population

We aimed to evaluate the contribution of the G-protein β3 subunit C825T (GNB3-C825T) polymorphism to essential hypertension (EH) in Han Chinese population by performing meta-analysis. A meta-analysis was performed in 12 case-control genetic association studies including 3,020 hypertension patients and 2,790 controls from MEDLINE (PubMed) and the China National Knowledge Infrastructure platforms. The STATA 10.0 software was used in analysis. Overall, there was no significant association between the GNB3-C825T polymorphism and EH in neither additive [TT vs. CC: OR (95 % CI) = 1.11 (0.74-1.69), P = 0.61; TC vs. CC: OR (95 % CI) = 1.08 (0.89-1.31), P = 0.42], nor dominant [TT + TC vs. CC: OR (95 % CI) = 1.11 (0.86-1.42), P = 0.43] and nor recessive [TT vs. TC + CC: OR (95 % CI) = 1.04 (0.75-1.44), P = 0.81] genetic models. Although further subgroup analysis found statistically significant results [T vs. C: OR (95 % CI) = 1.50 (1.05-2.15), P = 0.03] in the southern population, but after exclusion one particular study, the significant association was disappeared. No significant result was found in the northern Han Chinese population. There was no significant association identified between GNB3-C825T polymorphism and EH in Han Chinese population. Further larger sample and well-designed studies are needed to assess the genetic association particularly in the southern Han Chinese population.     

Further Daphniphyllum Alkaloids with Insecticidal Activity from the Bark of Daphniphyllum macropodum Miq.

Two new Daphniphyllum alkaloids, macropodumines J and K ( 1 and 2 , resp.), together with six known structurally related alkaloids, 3 – 8 , were isolated from the bark of Daphniphyllum macropodum Miq . The structures of the new compounds 1 and 2 were elucidated on the basis of a comprehensive analysis of their spectroscopic and chemical data. Macropodumine J ( 1 ) contains a CN group which is relatively rare in naturally occurring alkaloids. All isolated compounds were tested for their insecticidal activities against a number of insect species. Daphtenidine C ( 5 ) is the most active compound against Plutella xylostella. This is the first report of insecticidal properties of Daphniphyllum alkaloids.     

云南萝芙木pnae基因全长克隆及其序列分析

根据已知的其他物种PNAE酶cDNA序列设计引物,采用RT-PCR技术从云南萝芙木叶片中扩增获得pnae基因部分cDNA序列即PNAE酶基因中间大片段,再用RACE技术获得其两端序列。序列拼接得到完整的1 004 bp的PNAE酶基因,根据获得的序列,分析得到795 bp的开放阅读框,编码264个氨基酸。序列分析显示,云南萝芙木中PNAE酶氨基酸序列与蛇根木中的该酶氨基酸序列同源性高达90%,但和其他植物物种中的PNAE酶氨基酸序列,以及其他物种间的PNAE酶氨基酸序列同源性都不高,在40%-60%之间,表明不同物种中PNAE酶氨基酸序列不具有全序列的高度同源性。进一步序列分析发现,在各植物的PNAE酶氨基酸序列中都存在两个高度保守的氨基酸区域,表明不同物种中PNAE酶存在共同的高度保守区段。     

Peptide models of four possible insulin folding intermediates with two disulfides

The single-chain insulin (PIP) can spontaneously fold into native structure through preferred kinetic intermediates. During refolding, pairing of the first disulfide A20-B19 is highly specific, whereas pairing of the second disulfide is likely random because two two-disulfide intermediates have been trapped. To get more details of pairing property of the second disulfide, four model peptides of possible folding intermediates with two disulfides were prepared by protein engineering, and their properties were analyzed. The four model peptides were named [A20-B19, A7-B7]PIP, [A20-B19, A6-B7]PIP, [A20-B19, A6-A11]PIP, and [A20-B19, A7-A11]PIP according to their remaining disulfides. The four model peptides all adopt partially folded structure with moderate conformational differences. In redox buffer, the disulfides of the model peptides are more easily reduced than those of the wild-type PIP. During in vitro refolding, the reduced model peptides share similar relative folding rates but different folding yields: The refolding efficiency of the reduced [A20-B19, A7-A11]PIP is about threefold lower than that of the other three peptides. The present results indicate that the folding intermediates corresponding to the present model peptides all adopt partially folded conformation, and can be formed during PIP refolding, but the chance of forming the intermediate with disulfide [A20-B19, A7-A11] is much lower than that of forming the other three intermediates.     

弄岗北热带喀斯特季节性雨林15hm2动态监测样地树木死亡特征分析

以广西弄岗北热带喀斯特季节性雨林15 hm²森林动态监测样地为对象,结合2011年和2016年两次调查数据,分析5年间样地树木死亡个体的数量、径级结构和空间格局特征等。结果显示:2011年至2016年,样地有86.5%的树种出现了个体死亡的现象,死亡个体占个体总数的14.4%;死亡个体的聚集程度随空间尺度的增大而逐渐减弱;小径级个体死亡与周边邻体和环境的关联性较大;竞争是影响弄岗北热带喀斯特季节性云林树木死亡的主要因素。综合来看,北热带喀斯特季节性雨林内树木死亡并非是一个完全随机的过程,而是树木本身特征和生物与非生物环境共同作用的结果。     

Gc、Pi蛋白亚型的快速微量电泳分析

用快速微量等电聚焦技术对190名北京地区汉族健康人血清Gc蛋白亚型、Pi蛋白亚型进行分型鉴定和基因频率调查.上样量为1.5μl,电泳和染色各0.5h.Gc^1F=0.4891,Gc^1S=0.2432,Gc²=0.2678.观察值与期望值吻合良好.(∑X²=1.404,0.7<P<0.8).Pi^M₁=0.7542,Pi^M₂=0.1808,Pi^M₃=0.0650,观察值与期望值吻合也良好,(∑X²=1.1233,0.7<P<0.8).     

钝顶螺旋藻SP1(Spirulina platensis)对集约化养殖尾水氮磷的去除效果

针对集约化养殖模式后期硝酸盐氮和磷酸盐浓度较高的问题,实验设置生物絮团养殖尾水(BFW)和BG11培养液(BGW)两种水体环境,并以池塘常见优势微藻——绿色颤藻OC1(Oscillatoria chlorina)作为对比,研究分析了钝顶螺旋藻SP1(Spirulina platensis)对集约化养殖尾水氮磷的去除效果...     

Genetic diversity of Lilium tsingtauense in China and Korea revealed by ISSR markers and morphological characters

To study the genetic diversity and population structure of Lilium tsingtauense Gilg (Qingdao Lily), we collected 648 samples from 12 sites in China and Korea, and analyzed their Inter-Simple Sequence Repeat (ISSR) molecular markers and morphological characters. ISSR data revealed a relatively high genetic diversity at the species level, with 72.31% polymorphic loci, effective numbers of alleles of 1.437, average expected heterozygosity of 0.231 and Shannon’s information index of 0.369. Considerable genetic differentiation among the natural populations (G_ST = 0.144) and the gene flow (N_m = 1.487) were detected. AMOVA analysis and UPGMA-dendrogram suggested a hierarchical regional structure among populations, and spatial autocorrelation analysis showed a micro-scaled spatial structure. Furthermore, there was a high correlation between morphological characters and genetic parameters obtained from ISSR parameters. There was only a low genetic differentiation among the different morphological types of L. tsingtauence in China. Based on these findings, we recommend in situ and ex situ conservation strategies for the preservation of L. tsingtauense.