The in vitro development of cloned sheep embryos treated with Scriptaid and Trichostatin (A)

Introduction and aimsAlthough, it has been success in the generation of animal clones from somatic cells in various animal species, the information related to nuclear reprogramming of cloned embryos is found to be limited. This study aims to compares the effect of both Scriptaid (SCR) and Trichostatin (A) treatments in improving cloning efficiency, and embryos developmental rate of cloned sheep embryos in vitro. Three groups were formed, i.e., one SCR group, second TSA group, with both treatment concentrations of 5 nM, 50 nM, and 500 nM, respectively, and third were control group with 0 nM. Methods: Ovaries of slaughtered sheep were collected and oocytes were recovered from antral follicles using aspiration method and in vitro maturation of oocytes were done. Then zona dissecting with micropipettes and oocyte enucleation were carried out under the micromanipulator. Later nuclear transfer, cell fusion and activation were done via cell fusion machine. Finally the embryo cultured in incubating chamber at the CO2 incubator up to 9 days. The result: In general the results showed that when the concentration increases the cleavage rate increased. The cleavage rates of the SCNT embryos treated with SCR at different concentrations are closely related to cleavage rate of embryos treated with TSA at same concentration; such as 39.47% for 500 nM TSA, 38.09% for 500 nM SCR; 18.6% for 50 nM TSA, 19.17% for 50 nM SCR, and 22.64% for 5 nM TSA, 17.18% for 5 nM SCR. As for the control group, the cleavage rate of the SCNT embryos cleavage ratewere27.47%., 30% and 30.85% respectively for bothtreatments. While there is a significant difference in TSA treatments at an eight-cell stage at the concentration (5 and 50 nM TSA) compared to the all other cleavage cell stages of (500 nM TSA and control). Also their were a differences between (50 nM of TSA) compared to the (50 nM SCR). Also there were a significant differences between the 16 cell stage at the (500 nM TSA) compared to other treatment (5 nM, 50 nM TSA and control). Regarding the SCR there were a significant difference at 8 cell stage between (5 nM SCR), compared to the other treatment (50 nM, 500 nM SCR and control). Also there were a significant difference at 16 cell stage between (50 nM, and 500 nM SCR), compared to the other treatment (5 nM SCR and control). While in the development of the embryos reach to blastocyst stage the SCR and the control group show a higher rate, in compered to TSA that did not show any development to blastocyst stage. The total SCR treatment showed (3/41 = 7.31%), and the total control showed (4/89 = 4.49%) blastula stage. It concludes that SCR improve the final development blastula stage compared to the TSA treatments that did not improved embryos reach to final developmental blastula stages may be due to spices differences or to the toxicity of TSA, especially at higher concentrations.     

Uncontrolled zinc- and copper-induced oligomerisation of the human complement regulator factor H and its possible implications for function and disease

Polymorphisms in factor H (FH), a major regulator of complement activation, and the accumulation of high zinc concentrations in the outer retina are both associated with age-related macular degeneration. FH is inhibited by zinc, which causes FH to aggregate. To investigate this, we quantitatively studied zinc-induced FH self-association by X-ray scattering and analytical ultracentrifugation to demonstrate uncontrolled FH oligomerisation in conditions corresponding to physiological levels of FH and pathological levels of zinc in the outer retina. By scattering, FH at 2.8-7.0 μM was unaffected until [Zn] increased to 20 μM, whereupon the radius of gyration, R_G, values increased from 9 to 15 nm at [Zn] = 200 μM. The maximum dimension of FH increased from 32 to 50 nm, indicating that compact oligomers had formed. By ultracentrifugation, size-distribution analyses showed that monomeric FH at 5.57 S was the major species at [Zn] up to 60 μM. At [Zn] above 60 μM, a series of large oligomers were formed, ranging up to 100 S in size. Oligomerisation was reversed by ethylenediaminetetraacetic acid. Structurally distinct large oligomers were observed for Cu, while Ni, Cd and Fe showed low amounts of oligomers and Mg and Ca showed no change. Fluid-phase assays showed reduced FH activities that correlated with increased oligomer formation. The results were attributed to different degrees of stabilisation of weak self-dimerisation sites in FH by transition metals. The relevance of metal-induced FH oligomer formation to complement regulation and age-related macular degeneration is discussed.     

植物多肽激素

近几年研究表明,植物体内存在类似动物和酵母的多肽信号分子,调控植物生长发育以及调节植物对环境的响应。本文介绍了植物中的系统素,RALF,ENOD40,PSK,SCR,SLV3的特点和功能研究进展。     

Prediction of the Tertiary Structure of the Complement Control Protein Module

Complement control protein (CCP) modules, or short consensus repeats (SCR), exist in a wide variety of complement and adhesion proteins, principally the selectins. We have predicted the three-dimensional structure of a CCP module based upon secondary structural information derived by two-dimensional NMR [Barlow et al. (1991), Biochemistry 30, 997–1004]. Accordingly, the CCP is predicted to contain seven -strands with extensive hydrogen-bonding interactions, and shows a compact, globular structure. Comparison of this model to the X-ray structure of a kringle domain suggests that the CCP unit is more compact than a kringle structure, and that despite their similarities in size and disulfide bond format, the two are not homologous. Although the function of CCP domains is unknown, it is hoped that the structural model presented herein will facilitate further inquiry into how they contribute to so many systems of biological importance.     

Variability in odour reception in the peripheral sensory system of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

Abstract  Mixtures of single odours were used to explore the receptor response profile across individual antennae of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). Seven odours were tested including floral and green-leaf volatiles: phenyl acetaldehyde, benzaldehyde, β-caryophyllene, limonene, α-pinene, 1-hexanol, 3 Z -hexenyl acetate. Electroantennograms of responses to paired mixtures of odours showed that there was considerable variation in receptor tuning across the receptor field between individuals. Data from some moth antennae showed no additivity, which indicated a restricted receptor profile. Results from other moth antennae to the same odour mixtures showed a range of partial additivity. This indicated that a wider array of receptor types was present in these moths, with a greater percentage of the receptors tuned exclusively to each odour. Peripheral receptor fields show variation in the spectrum of response within a population (of moths) when exposed to high doses of plant volatiles. This may be related to recorded variation in host choice within moth populations as reported by other authors.     

甘蓝自交不亲和反应的细胞信号转导

S受体激酶(S—receptor kinase,SRK)和S位点富含半胱氨酸(S-locus cysteine-rich,SCR)分别是甘蓝柱头和花粉中导致自交不亲和反应的决定性蛋白质因子。本文就SRK、SCR的结构和功能加以综述,阐明两者在细胞信号转导中的作用。     

Zinc binding to the Tyr402 and His402 allotypes of complement factor H: possible implications for age-related macular degeneration

The Tyr402His polymorphism of complement factor H (FH) with 20 short complement regulator (SCR) domains is associated with age-related macular degeneration (AMD). How FH contributes to disease pathology is not clear. Both FH and high concentrations of zinc are found in drusen deposits, the key feature of AMD. Heterozygous FH is inhibited by zinc, which causes FH to aggregate. Here, zinc binding to homozygous FH was studied. By analytical ultracentrifugation, large amounts of oligomers were observed with both the native Tyr402 and the AMD-risk His402 homozygous allotypes of FH and both the recombinant SCR-6/8 allotypes with Tyr/His402. X-ray scattering also showed that both FH and SCR-6/8 allotypes strongly aggregated at > 10 μM zinc. The SCR-1/5 and SCR-16/20 fragments were less likely to bind zinc. These observations were supported by bioinformatics predictions. Starting from known zinc binding sites in crystal structures, we predicted 202 putative partial surface zinc binding sites in FH, most of which were in SCR-6. Metal site prediction web servers also suggested that SCR-6 and other domains bind zinc. Predicted SCR-6/8 dimer structures showed that zinc binding sites could be formed at the protein-protein interface that would lead to daisy-chained oligomers. It was concluded that zinc binds weakly to FH at multiple surface locations, most probably within the functionally important SCR-6/8 domains, and this explains why zinc inhibits FH activity. Given the high pathophysiological levels of bioavailable zinc present in subretinal deposits, we discuss how zinc binding to FH may contribute to deposit formation and inflammation associated with AMD.     

oSCR: a spatial capture–recapture R package for inference about spatial ecological processes

Spatial capture–recapture (SCR) methods have become widely applied in ecology. The immediate adoption of SCR is due to the fact that it resolves some major criticisms of traditional capture–recapture methods related to heterogeneity in detectabililty, and the emergence of new technologies (e.g. camera traps, non‐invasive genetics) that have vastly improved our ability to collection spatially explicit observation data on individuals. However, the utility of SCR methods reaches far beyond simply convenience and data availability. SCR presents a formal statistical framework that can be used to test explicit hypotheses about core elements of population and landscape ecology, and has profound implications for how we study animal populations. In this software note, we describe the technical basis and analytical workflow of oSCR, an R package for analyzing spatial encounter history data using a multi‐session sex‐structured likelihood. The impetus for developing oSCR was to create an accessible and transparent analysis tool that allows users to conveniently and intuitively formulate statistical models that map directly to fundamental processes of interest in spatial population ecology (e.g. space use, resource selection, density and connectivity). We have placed an emphasis on creating a transparent and accessible code base that is coupled with a logical workflow that we hope stimulates active participation in further technical developments.