Promiscuous females avoid inbreeding by controlling sperm storage

Recent studies in a variety of species have shown that polyandrous females are somehow able to bias paternity against their relatives postcopulation, although how they do so remains unknown. Field crickets readily mate with their siblings, but when also mated to an unrelated male, they produce disproportionately fewer inbred offspring. We use a new competitive microsatellite polymerase chain reaction technique to determine the contribution of males to stored sperm and subsequent paternity of offspring. Paternity is almost completely predicted by how much sperm from a particular male is stored, and unrelated males contribute more sperm to storage and have a corresponding higher paternity success.     

Assessment of prey overlap between a native (Polistes humilis) and an introduced (Vespula germanica) social wasp using morphology and phylogenetic analyses of 16S rDNA

Abstract In newly invaded communities, interspecific competition is thought to play an important role in determining the success of the invader and its impact on the native community. In southern Australia, the native Polistes humilis was the predominant social wasp prior to the arrival of the exotic Vespula germanica (Hymenoptera: Vespidae). Both species forage for similar resources (water, pulp, carbohydrate and protein prey), and concerns have arisen about potential competition between them. The aim of this study was to identify the protein foods that these wasps feed on. As many prey items are masticated by these wasps to the degree that they cannot be identified using conventional means, morphological identification was complemented by sequencing fragments of the mitochondrial 16S rRNA gene. GenBank searches using blast and phylogenetic analyses were used to identify prey items to at least order level. The results were used to construct complete prey inventories for the two species. These indicate that while P. humilis is restricted to feeding on lepidopteran larvae, V. germanica collects a variety of prey of invertebrate and vertebrate origin. Calculated values of prey overlap between the two species are used to discuss the implications of V. germanica impacting on P. humilis. Results obtained are compared to those gained by solely 'conventional' methods, and the advantages of using DNA-based taxonomy in ecological studies are emphasized.     

Expression of apoptosis-related genes in the endometrium of polycystic ovary syndrome patients during the window of implantation

The present study investigated the expression of the apoptosis-related genes fas-associated via death domain (FADD) and Bcl-2 in the endometrium during the window of implantation in polycystic ovary syndrome (PCOS) patients. The aim was to explore the role of cell apoptosis in endometrial receptivity during this period. The subjects were divided into experimental and control group. The experimental group comprised 12 infertile women with PCOS, and the control group comprised 12 women who were infertile because of tubal pathological factors but had normal menstrual cycles. Endometria were collected by biopsy 7d after ovulation. Six samples from each group were randomly selected and subjected to gene chip analyses. The expression of endometrial FADD and Bcl-2 was determined by immunohistochemistry, and cell apoptosis was detected by the TUNEL method. Compared with the control group, 194 differentially expressed genes were found in the PCOS group, 102 of which were upregulated and 92 were downregulated. The differentially expressed genes were divided into 15 types according to function. Among the nine genes related to cell apoptosis, five (including Bcl-2) were upregulated and four were downregulated (including FADD). Bcl-2 expression during the window of implantation in the PCOS group increased compared with the control group, showing a significant difference (P<0.05). FADD expression in the PCOS group notably decreased compared with that in the control group, which also showed a significant difference (P<0.05). Cell apoptosis analysis showed a significant difference between the average apoptotic indices in the PCOS and control groups (P<0.05). Significant differences were observed between the endometrial gene expression in the PCOS and control groups. The decrease in cell apoptosis during the window of implantation in PCOS patients may be one of the causes of the reduced endometrial receptivity.     

REV3基因对结肠癌细胞遗传信息表达的影响

利用RNA干扰技术降低REV3基因在人类结肠癌细胞(SW480)中的表达, 以荧光实时定量PCR检测REV3表达量的降低情况, 选择低表达效率具有统计学意义的细胞作为实验组细胞。运用细胞生长曲线、MTT、微核和姐妹染色单体交换等方法, 对实验组和对照组细胞进行细胞生长周期、增殖变化情况和遗传信息表达等指标的检测。结果显示: REV3低表达的结肠癌实验组细胞在细胞增殖以及细胞的微核和姐妹染色单体交换等遗传信息表达均明显低于结肠癌对照组细胞, 实验结果具有统计学意义(P＜0.05); 结肠癌的两对照组间(阴性和空白)的结果虽然有一定的差异, 但没有统计学意义。研究结果提示, REV3低表达时, 可能对结肠癌细胞(SW480)的生长与增殖产生影响, 并对微核和姐妹染色单体交换等遗传不稳定现象的产生有一定的抑制作用。     

A novel qPCR protocol for the specific detection and quantification of the fuel-deteriorating fungus Hormoconis resinae

A wide variety of fungi and bacteria are known to contaminate fuels and fuel systems. These microbial contaminants have been linked to fuel system fouling and corrosion. The fungus Hormoconis resinae, a common jet fuel contaminant, is used in this study as a model for developing innovative risk assessment methods. A novel qPCR protocol to detect and quantify H. resinae in, and together with, total fungal contamination of fuel systems is reported. Two primer sets, targeting the markers RPB2 and ITS, were selected for their remarkable specificity and sensitivity. These primers were successfully applied on fungal cultures and diesel samples demonstrating the validity and reliability of the established qPCR protocol. This novel tool allows clarification of the current role of H. resinae in fuel contamination cases, as well as providing a technique to detect fungal outbreaks in fuel systems. This tool can be expanded to other well-known fuel-deteriorating microorganisms.     

Variability of phytoplasma associated with few ornamental crop species in Uttar Pradesh,India

Abstract

The economic importance of ornamentals has been advancing significantly in many countries due to continuous international demand. Like other crops, ornamental plants are also affected by a number of pathogens and the phytoplasmas diseases are equally important group of pathogens which is responsible for damaging the different ornamental plant species and thereby affecting their market value. In the present investigation, total 24 symptomatic leaf samples of 8 ornamental plant species (C. roseus, R. rubiginosa, C. variegatum, Z. elegans, J. gendurusa, T. erecta, H. rosa sinensis, J. sambrac) were analyzed which were found positive in nested PCR assays with R16F2n/R16R2 primers. The phytoplasma associated with ornamental plant species collected from different districts of UP in the present investigation are belongs to 16Sr I, II, VI and XIV group.     

蚜虫不同分类阶元之间遗传距离的RAPD-PCR研究(英文)

应用RAPD PCR技术研究了蚜虫不同分类阶元的遗传距离。从 2 0种随机引物中筛选出 7种引物 ,并用它们的扩增结果进行Nei’s的遗传距离的计算和聚类分析。结果表明 :蚜虫的遗传距离在不同科之间为 0 .56 6 3± 0 .0 6 89,亚科之间为 0 .4 586± 0 .0 2 142 ,属之间为 0 .3816± 0 .0 375,种之间为 0 .2 975±0 0 6 2 7,同一种的不同种群之间为 0 .0 4 33± 0 .0 2 2 2。同时 ,本研究结果为在DNA水平上研究蚜虫的分化和种的鉴定 ,尤其是对于近缘种的鉴定具有重要的价值。     

A comparative study of the O-3 reactivity of isomeric N-dimethylmaleoyl-protected d-glucosamine and d-allosamine acceptors

Four isomeric N-dimethylmaleoyl 4,6-O-benzylidene-protected d-hexosamine acceptors (2, 3, 4, and 5) with all possible configurations at C-1 and C-3 (e.g., derived from d-glucosamine and d-allosamine) were prepared, and the assessment of their O-3 relative reactivity through competition experiments using the known per-O-acetylated d-galactopyranosyl trichloroacetimidate donor (15) was then carried out. The reactivities are in the order 4 ? 2 > 5 > 3. The analysis of the NMR spectra of 2–5 at different temperature and modeling experiments carried out on analogs of 2–5 (DFT) and on the acceptors themselves (MM) are coincident, and have helped to establish the stability of the different hydrogen bonds, and of the conformers which carry them. The whole results suggest that the electronic effects (hydrogen bonds) are required to explain the observed trend, in spite of the axial conformation of the most reactive hydroxyl group. The steric effects appear only when hydrogen bonds are weak.