Embryo development

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Elutriate preparation affects embryo development test with Paracentrotus lividus: An in-depth study on the differences between two protocols and three different sediment/water mixing times

Elutriate preparation affects embryo development test with Paracentrotus lividus: An in-depth study on the differences between two protocols and three different sediment/water mixing times

Embryo-development, ecotoxicology Environmental monitoring A B S T R A C T Coastal areas are under continuous and increasing pressure from different human activities. A mixture of con- taminants (e.g. hydrocarbons, pesticides, persistent organic pollutants (POPs), emerging contaminants, and others), originating mainly from populated, industrialised and agricultural areas, can reach the marine envi- ronment through different means such as wastewater discharge, soil runoffs, leaching from agriculture, and volatilisation/deposition. In this context, marine sediments have increasingly been considered repositories for a variety of pollutants that can accumulate and be stored for long periods, acting as a secondary source of con- taminants during subsequent dredging operation or vessel manoeuvring. Chemical and ecotoxicological analyses of sediments are routinely conducted to evaluate the potential hazard/risk to the environment, either on bulk sediment or elutriate. In general, sediment elutriates are commonly prepared according to ASTM Guide even if alternative protocols are proposed by USACE for the various condition that they have to represent. The goal of the present study was to determine if the toxicological properties of ASTMprepared elutriates are comparable to those obtained from the USACE protocol. Sediment coming from 3 harbours (Olbia, Cagliari, and Toulon), as part of the “Se.D.Ri.Port” Interreg Project, were processed to obtain elutriates according to ASTM Guide and USACE Dredging Elutriate protocol and tested with the sea urchin Paracentrotus lividus embryo development test. Moreover, the significance of different stirring times of water/sediment mixture (1 h, 3 h, and 24 h) was tested with both the ASTM and USACE protocol. In addition to the biological analysis, for each sediment sample, heavy metals concentration, granulometry, and organic matter were determined. Even if for the ports of Toulon and Cagliari, the ASTM and USACE elutriates showed comparable results with P. lividus bioassay, for the port of Olbia the two protocols showed different criticalities. Preliminary results show that for the site Olbia elutriates prepared with the USACE protocol resulted in higher toxicity than elutriates obtained with ASTM (p < 0.001). In conclusion, differences in preparation protocols appear to be significant and can lead to different results in biological testing. To overcome this problem and to obtain more reliable evaluations of risk to the environment, standardisation and regulation must be the next goals in sediment management procedure.
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Genome-wide analysis reveals gene expression and metabolic network dynamics during embryo development in Arabidopsis

Genome-wide analysis reveals gene expression and metabolic network dynamics during embryo development in Arabidopsis

In this study, we have successfully isolated live zygote to late stage embryos of Arabidopsis and studied global gene expression patterns that regulate embryogenesis. This represents the first genome-wide gene expression profiling of embryogenesis in Arabidopsis and in plants, and the data presented here will serve as foundational resource for future studies addressing fundamental molecular and developmental mechanisms that govern plant embryogenesis. The entire dataset (Supplemental Table S1) along with digital gene expression information (Supplemental Fig. S1B) for Arabidopsis embryo development is available at http://www2.bri.nrc.ca/plantembryo/ . The highlighted in-depth analyses clearly show the dynamics of embryo-specific gene expression and metabolic pathways as the embryo progresses from a zygote to a physiologically mature embryo. The metabolic networks developed in this study provide an integrated view of modulated and progressively elaborated biochemical
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Somatic embryo development in maritime pine (Pinus pinaster): a 2-DE proteomic analysis

Somatic embryo development in maritime pine (Pinus pinaster): a 2-DE proteomic analysis

Development of clonal propagation method, such as somatic embryogenesis (SE) has potentially numerous applications such as the production of a large number of genetically improved plants. However it is necessary to optimise somatic embryo development, which remains difficult in pine species. Since the early protocols of SE were developed for spruce species (Picea), it was assumed that they would be applicable to pines; however, it became apparent that pines were less responsive. One limitation to large-scale propagation of majority of commercial pine species through SE is the lack or low somatic embryo maturation efficiency, which result in the inability to capture certain families. This has caused great concerns among breeders and foresters of potential adverse selection pressure.
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Porcine embryo development and fragmentation and their relation to apoptotic markers: a cinematographic and confocal laser scanning microscopic study.

Porcine embryo development and fragmentation and their relation to apoptotic markers: a cinematographic and confocal laser scanning microscopic study.

et al. 2003). Annexin V has a specific and high affinity for phosphatidylserine that redistributes to the outer leaflet of the cell membrane in an apoptotic cell (Martin et al. 1995). By using propidium iodide staining to assess mem- brane permeability in addition to the annexin V, it is poss- ible to distinguish apoptosis from necrosis (Levy et al. 1998, van den Eijnde et al. 1997). TUNEL allows the assessment of another classic feature of apoptosis namely nuclear DNA fragmentation (Gavrieli et al. 1992). Using these conservative criteria for apoptosis, the incidence of false positive results due to necrosis, misinterpretation of prophase nuclei or nuclear fragmentation independent of apoptosis should be reduced to a minimum. Because the annexin V staining is characteristic for early apoptosis (Martin et al. 1995), false negative results could have occurred only in 2 embryos where nuclei were fragmen- ted and the annexin V staining was positive, but where no TUNEL signal was detected. The average ACR of day 7 blastocysts (3.4%) in our study was higher than the aver- age ACR estimated for in vivo embryos flushed at day 4 (0.4%) (Rubio Pomar et al. 2004) but numerically lower than the average ACR of in vitro produced day 7 blasto- cysts (4.9%) (Hao et al. 2003). These results indicate that apoptosis is a natural process of porcine preimplantation embryo development that is increased by suboptimal in vitro culture conditions.
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Gene expression atlas of embryo development in Arabidopsis

Gene expression atlas of embryo development in Arabidopsis

Diferential gene expression (DEG) analysis High-quality reads were iltered using the Trimmomatic tool (Bolger et al. 2014 ) with default parameters to remove sequencing adapters and low-quality reads. A quality check was performed with FastQC (Andrews 2010 ), and the il- tered reads were mapped to the Arabidopsis genome TAIR10 using STAR (Dobin et al. 2013 ). Read counting was carried out with HTSeq (Anders et al. 2015 ). Analysis of diferen- tial expression genes (DEGs) was performed with DESeq 2 to normalize the raw reads and identify DEGs in pairwise comparisons between each stage of embryo development (Love et al. 2014 ). An experimental design based on the DESeq 2 R package was applied to raw read counts for all libraries with p value (adjusted) < 0.05, log2FoldChange > 1 and < − 1 to relect transcriptional regulation across all seven developmental stages, as shown in Supplementary Data S1. Raw data counts were normalized by library size and it to a negative binomial model. Principal component analysis (PCA) was calculated with the built-in plotPCA function provided by the DESeq 2 tool. All DEGs were annotated by querying the open reading frame (ORF) sequences against the non-redundant protein database (with BLAST) using an e-value cutof of 10 −5 and reporting the maximum “hit” sequence per query. Diferential expression of genes was determined to be signiicant if a log2 (fold change) of > 1 or < − 1 and p value (adjusted) < 0.05 was obtained.
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Dynamic changes in gene expression during human early embryo development: from fundamental aspects to clinical applications.

Dynamic changes in gene expression during human early embryo development: from fundamental aspects to clinical applications.

Epigenetic regulation of human early embryonic development Epigenetics refers to a collection of mechanisms that can cause a change in the phenotype of a cell without altering its DNA sequence ( Goldberg et al., 2007 ). Early embryonic development is regulated epigenetically. During the development process, the epigenetic signature changes as the cell enters fertilization and/or differentiation. DNA methylation is an important epigenetic event, regulating gene expression and chromatin structure in any developmental processes including gene imprinting and embryogenesis ( Kafri et al., 1992 ). To maintain methylated DNA, DNA methyltransferases ( DNMTs ) are necessary ( Vassena et al., 2005 ). This family of enzymes is divided into two major classes: DNMT1 and DNMT3 (including DNMT3A and DNMT3B DNMT1 ). enzyme is the main methyltransferase by far and its exceptional preference for hemimethylated DNA indicates its role in the maintenance of methylated status during DNA replication. Genetic studies have suggested that DNMT1 may play a role in the methylation of repeat elements in growing oocytes ( Gaudet et al., 2004 ). Our genes expression data indicate that the DNMT1 mRNA was overexpressed in mature MII oocytes and decreased progressively in embryos on day-3 and in hESCs ( Figure 3B ), revealing that the oocyte-specific DNMT1 transcript is expressed in human oogenesis and persists in embryos at day-3. DNMT3B transcripts were detected in mature MII oocytes and hESCs ( Assou et al., 2009 ), and the expression of DNMT3A was enriched in undifferentiated hESCs ( Assou et al., 2007 Huntriss et al., 2004 Richards et al., 2004 ; ; ), indicating that the DNMT3 family methyltransferases are candidate epigenetic regulators during preimplantation development. Both and enzymes are involved in methylation processes with different substrate preferences. acts
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Multi-scale analysis of early molecular events during Pinus pinaster Ait. somatic embryo development under reduced water availability

Multi-scale analysis of early molecular events during Pinus pinaster Ait. somatic embryo development under reduced water availability

International Conference of the IUFRO Working Party 2.09.02: Somatic Embryogenesis and Other Vegetative Propagation Technologies, International Union of Forest Research Organisations (IU[r]

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Phosphorylation of the microtubule-severing AAA+ enzyme Katanin regulates C. elegans embryo development

Phosphorylation of the microtubule-severing AAA+ enzyme Katanin regulates C. elegans embryo development

Figure S1. Construction and characterization of a C. elegans line expressing endogenously tagged MEI-2 with sGFP. (A) Schematics of the mei-2 locus showing insertion of sGFP before the ATG initiation codon by CRISPR/Cas9-based genome editing. The nucleotide and protein sequence of the end of the sGFP (green) and the linker (purple) are indicated. (B) Western blot analysis of embryonic extracts from N2 or sGFP::MEI-2 strain exposed to mock (control), mei-2, or mei-1 RNAi using GFP and MEI-1 antibodies (upper panel) and tubulin (middle panel) antibodies. The lower panel shows Ponceau staining of the membrane. (C) Graphs showing the percentage of viability of N2 or sGFP::MEI-2 strain exposed to mock (Ctrl), mei-2, or mei-1 RNAi. Error bars represent SEM. n = 4 independent experiments performed in triplicate with >100 embryos each. (D) Spinning disk confocal micrographs of adult worm expressing sGFP::MEI-2 (in green) and mCherry::HIS-11 (in red) exposed to control RNAi. Arrowheads point to mitotic spindles. Sp, spermathecal; ooc, oocytes. The asterisk (*) indicates the –1 oocytes arrested in prophase of meiosis I. Note that in this worm, the oocytes adjacent to the spermatheca have resumed meiosis. (E) Spinning disk confocal micrographs of early embryos expressing sGFP::MEI-2 (in green) and mCherry::HIS-11 (in red) during meiosis. The anterior of the embryo is oriented toward the left in this and other figures. Scale bar represents 5 µm. (F) Spinning disk confocal micrographs of adult worm expressing sGFP::MEI-2 (in green) and mCherry::HIS-11 (in red) exposed to mei-2(RNAi). Insets are higher magnifications of the boxed regions. Head of the worm is on the left of the picture. The full worm was reconstituted from ∼10 different views and assembled using Photoshop. The germline is delimited by dashed lines. Sp, spermatheca; Ooc, oocytes; Emb, embryos; *, –1 oocyte. Scale bar represents 50 µm.
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My Corporis Fabrica Embryo: An ontology-based 3D spatio-temporal modeling of human embryo development

My Corporis Fabrica Embryo: An ontology-based 3D spatio-temporal modeling of human embryo development

rules have been obtained). RDF datasets equipped with rules allow the capture of most of OWL \cite{owl} con- straints that are useful in practice, such as the transitivity or symmetry properties, as well as domain-specific rules with practical relevance for users in many domains of interest. The 3D graphical tool was developed using the 3D open source software Blender [43]. All the 3D surfaces where procedurally handled using Python [44] scripting within the Blender framework. The ovoids were handled as Blender parameterized primitives. The implicit surfaces were repre- sented as a set of points along the trajectory of the ducts while the field function and the representative mesh of the isovalue was handled by Blender software. Finally, the shape representing the boundary of the embryo was created inter- actively using Blender interface. All the coordinates param- eterizing the shapes and its animation were expressed locally with respect to the embryo main axes and size. The coordinates were queried within our Python script to be directly usable within the Blender framework.
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Embryo transfer as a method to eliminate pathogenic agents in a rabbit colony

Embryo transfer as a method to eliminate pathogenic agents in a rabbit colony

All selected embryos were cryopreserved. This is the only technique to associate a stamping out in good conditions and a perfect synchronization between donors and recipients. Moreover, frozen embryos can be stored for further transfers. Different stages of embryo development can be frozen. Collection of day 3 embryos was chosen because morulae present the best resistance to cryopreservation (Bank and Maurer, 1974; Tsunoda and Sugié, 1977). Zygote collection can be an other way to work in order to reduce risks of disease transmission by the mucin coat. At the zygote stage, the mucin layer is already present although it is thinner than in later stages of development. Nevertheless, this procedure may reduce the number of pups after transfer. This is caused by the fact that selection of good embryos is less efficient. In our
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A robust auxin response network controls embryo and suspensor development through a basic Helix Loop Helix transcriptional module

A robust auxin response network controls embryo and suspensor development through a basic Helix Loop Helix transcriptional module

d Top Institute Food & Nutrition, Nieuwe Kanaal 9A, 6709 PA Wageningen, the Netherlands ORCID IDs: 0000-0002-7742-7817 (T.R.); 0000-0002-0986-2219 (C.I.L.-P.); 0000-0002-6198-3763 (J.R.W.); 0000-0002-2139-0795 (M.B.); 0000-0003-1954-3542 (G.H.); 0000-0003-0790-5569 (R.D.); 0000-0003-4378-141X (D.W.) Land plants reproduce sexually by developing an embryo from a fertilized egg cell. However, embryos can also be formed from other cell types in many plant species. Thus, a key question is how embryo identity in plants is controlled, and how this process is modi fied during nonzygotic embryogenesis. The Arabidopsis (Arabidopsis thaliana) zygote divides to produce an embryonic lineage and an extra-embryonic suspensor. Yet, normally quiescent suspensor cells can develop a second embryo when the initial embryo is damaged, or when response to the signaling molecule auxin is locally blocked. Here we used auxin- dependent suspensor embryogenesis as a model to determine transcriptome changes during embryonic reprogramming. We found that reprogramming is complex and accompanied by large transcriptomic changes before anatomical changes. This analysis revealed a strong enrichment for genes encoding components of auxin homeostasis and response among misregulated genes. Strikingly, deregulation among multiple auxin-related gene families converged upon the re- establishment of cellular auxin levels or response. This finding points to a remarkable degree of feedback regulation to create resilience in the auxin response during embryo development. Starting from the transcriptome of auxin-deregulated embryos, we identi fied an auxin-dependent basic Helix Loop Helix transcription factor network that mediates the activity of this hormone in suppressing embryo development from the suspensor.
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Comparison of the zebrafish embryo toxicity assay and the general and behavioral embryo toxicity assay as new approach methods for chemical screening

Comparison of the zebrafish embryo toxicity assay and the general and behavioral embryo toxicity assay as new approach methods for chemical screening

alternative model to animal testing [ 2 – 9 ]. The zebrafish larval model of toxicity testing is now included as an Organization for Economic Cooperation and Development (OECD) Fish Embryo Toxicity (FET) model [ 10 , 11 ]. In addition to the parameters set out by these guidelines, numerous other toxicity testing protocols and paradigms have been developed that make use of early-stage zebrafish embryos, commonly referred to as Zebrafish Embryo Toxicity (ZET) assays. The majority of these models have been developed as teratogenicity assays that evaluate the effects of potential toxicants on embryo development. A number of different exposure timelines have been used within the first 5 days of development. These include beginning test compound exposure between 4 and 24 h post fertilization (hpf), followed by the assessment of toxicity, often every 24 h, up to 72, 96 or 120 hpf [ 7 , 12 – 15 ]. In addition to the teratogenic ZET assays, a toxicity testing model was developed in our lab which exposed larvae to potential toxic compounds beginning at 72 hpf and evaluated visible indicators of toxicity and changes in behaviour at 120 hpf [ 16 ]. Since body patterning, organogenesis, and swim bladder inflation is complete by 72 hpf [ 17 ], we hypothesize this assay to be more of a general toxicity assay rather than one which evaluates teratogenicity. This assay, termed the General and Behavioral Toxicity (GBT) assay, may then act as a complementary test to the previously developed ZET teratogenic assays.
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The actors of human implantation: gametes, embryo and endometrium

The actors of human implantation: gametes, embryo and endometrium

During spermiogenesis, the final phase of spermatogenesis after meiosis, chromatin is radically reorganized and undergoes an extreme condensation resulting in a shift from a nucleosome-based genome organization to the sperm-specific, highly compacted nucleoprotamine structure. The DNA double helix of somatic cells is indeed organized into chains of nucleosomes by a family of nuclear proteins, the histones. At spermiogenesis, histones are mostly replaced by transition proteins, which are themselves replaced by two types of specific nuclear proteins of the male gametes, protamines 1 and 2. These proteins are particularly rich in arginines (which help to neutralize negative charges of DNA phosphate groups), in cysteines (which allow the formation of disulfide bonds intra and inter –protamines), and in histidines (which, in combination with cysteines, permit the establishment of zinc bridges). Because of this particular composition, the sperm chromatin fibers are strongly compacted, and have almost a crystalline organization (Bjorndahl and Kvist, 2010). In human sperm, about 85% of histones are replaced by protamines, while the other 15% remain. So sperm chromatin is organized predominantly in toroids (by protamines), the rest being organized in nucleosomes (by histones) or attached to the nuclear matrix (MARs: Matrix attached regions) (Govin et al., 2011; Jonge and Barratt, 2006; Ward, 2010). Recent data support the idea that region-specific programming of the haploid male genome is of high importance for the post-fertilization events and for successful embryo development. The molecular basis of post-meiotic male genome reorganization and compaction constitutes one of the last black boxes in modern biology of reproduction. Although the successive transitions in DNA packaging have been well described, the molecular factors driving these near genome-wide reorganizations remain obscure (Rousseaux et al., 2011).
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Does Embryo Culture Medium Influence the Health and Development of Children Born after In Vitro Fertilization?

Does Embryo Culture Medium Influence the Health and Development of Children Born after In Vitro Fertilization?

In humans, studies were essentially based on early embryo development or implantation rates [ 28 ], and those analysing birthweight and post-natal growth remain limited [ 5 , 16 ]. How- ever, some studies, again revealed that the composition of the culture medium could affect early embryonic and foetal development and even birthweight [ 7 , 8 ]. Meta-analyses reported, after correction for confounding factors, that ART-conceived singletons also had a higher risk of prematurity and perinatal morbi-mortality than children conceived naturally [ 29 , 30 ]. In our study, after identical adjustments, no difference was highlighted between the two culture media at this step. Finally, we found no increased risk of either minor and major malformations or physical health problems until the age of five years in singletons from the SSM group although this medium was underachieving. We have to keep in mind that this absence of difference is probably due to the fact that the size of our children cohort is relatively small to evidence non- major differences between groups. However, this study revealed that the children from the Global group were significantly less likely to display developmental problems than were those of the SSM group. Importantly, this effect of culture medium on child development was the same in every CDI domain, including social skills, self-help, gross and fine motor skills, lan- guage comprehension, expressive language, letter and number knowledge. The method used in this work to determine the developmental outcomes has been selected based on its psychomet- ric properties showing a high sensitivity and specificity as well as a good predictive value (i.e. in comparison with standard measure of developmental status such as neuropsychological tests) [ 12 – 14 ]. To our knowledge, no study evaluated the developmental and cognitive status of ART-singletons according to the type of culture medium. However, some studies on mental and motor development of ART-children showed that children were more likely to have delayed mental and motor development and a lower intelligence quotient [ 31 – 33 ] whereas other studies reported no adverse cognitive and motor outcomes [ 32 , 34 – 36 ].
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Cell Pairings for Ascidian Embryo Registration

Cell Pairings for Ascidian Embryo Registration

Index Terms— Fluorescence microscopy, symmetry detection, embryogenesis, cell-to-cell mapping 1. INTRODUCTION A central aim in developmental biology is to better understand how each tissue of an embryo progressively acquires its functional shape, a process called morphogenesis. Image-based studies therefore rep- resent a method of choice. Current live microscopy techniques allow the acquisition of temporal sequences of 3D images with a spatio- temporal resolution high enough to follow embryo development at sub-cellular scale [1]. An automatic framework to register individ- ual cells from distinct developing embryos would allow quantifying the variability in embryo development at the cellular level, which is a major issue in morphogenesis studies.
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From Embryo Research to Therapy

From Embryo Research to Therapy

A more metaphysical concern sometimes put forward is that of a threat to individual identity. 34 Only mitochondrial replacement therapy is concerned here, given that the restoration of diploidy does not modify the individual’s genome, often considered the basis of this identity. The response to this objection was that only the mitochondrial DNA is concerned, i.e. 0.1% of the human DNA. The mitochondrial DNA also does not appear to play a role in the phenotypic characteristics determining the structure (or essence) of the person. In its rejection of an appeal by the Jérôme Lejeune Foundation against a French research project concerning the interaction of the nuclear and mitochondrial genomes during embryo development prior to implantation, the Montreuil Administrative Court also emphasized the fact that there is no modification of the nuclear genome: “Neither the aim nor the effect of the approved project is to transfer foreign genes into the nuclear DNA of the embryos used”. 35 As a consequence, some authors even assert that mitochondrial
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Parental-to-embryo switch of chromosome organization in early embryogenesis

Parental-to-embryo switch of chromosome organization in early embryogenesis

Mouse embryo collection, single-cell dissociation and formaldehyde fixation Five-week-old female C57BL/6J mice were purchased from Charles River. Animal care and use for this study were performed in accordance with the recommendations of the European community (2010/63/ UE). All experimental protocols were approved by the ethics commit- tee of the Institut Curie CEEA-IC118 under the number APAFIS#8812- 2017020611033784v2, given by national authority in compliance with the international guidelines. When stated, intraperitoneal injection of 5 IU pregnant mare’s serum gonadotropin, followed 46 h later by injec- tion of 5 IU human gonadotropin, were applied to induce ovulation of female mice. DNA FISH was performed on embryos collected from superovulated C57BL/6J (B6) female mice (except for the blastocyst stage), mated with C57BL/6J (B6) male mice. The single-cell HiC pro- tocol was applied to blastomeres of embryos collected from crosses between C57BL/6J (B6) female mice and CAST/EiJ male mice. In the case of the one-cell, two-cell and four-cell stages, some embryos were col- lected after female superovulation. Embryos were collected from the reproductive tracts in M2 medium at defined time periods according to mating and/or hCG administration (given in this order): 14 h or 21 h for 1-cell stage (pronuclear stage 3 or 4), 37 h or 44 h for late 2-cell stage, 48 h or 55 h for 4-cell stage, 55 h or 62 h for 8-cell stage and 80 h for blastocyst stages (approximately 60 to 64 cells) (64-cell stage). B6 pure oocytes were collected 15 h after hCG injection. Embryos were included in the analyses when they showed a normal morphology and the correct number of blastomeres for their developmental stage. Zona pellucida and polar bodies were removed using acid Tyrode’s solution and/or gentle pipetting (except in a few cases for the blastocyst stage). Embryos were incubated in Ca 2+ - and Mg 2+ -free M2 medium for 5 to 30
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The FRK1 mitogen-activated protein kinase kinase kinase (MAPKKK) from Solanum chacoense is involved in embryo sac and pollen development

The FRK1 mitogen-activated protein kinase kinase kinase (MAPKKK) from Solanum chacoense is involved in embryo sac and pollen development

Takeuchi and Higashiyama, 2011 ). To determine if the ScFRK1 transgenic lines are also affected in pollen tube guidance, a semi in vivo pollen tube guidance system was used. The Scfrk1-S1 line was selected for this analysis as it showed the lowest percentage of functional embryo sacs. WT lowers were hand pollinated with fully compatible pol- len and styles were collected 24 h later. The detached styles are then laid on a microscopic slide covered with pollen tube growth medium with ovules placed at ~650  μm from the cut style end, a distance corresponding to the radius of the ovary. Pollen tubes start to emerge ~30 hours after pollination (HAP). Figure  7 shows the result of two dif- ferent assay systems. First, a single-choice assay was used with ovules from either WT or Scfrk1-S1 plants as shown in Fig. 7A , B , respectively. Attraction was determined from the bulk pattern obtained, with each pollinated style being counted as one assay. An attraction phenotype was scored when there was a clear trend and the majority of the pol- len tubes grew toward the ovules as observed in Fig.  7A Fig. 6. Comparative cytological analyses of WT and Scfrk1-S1 pollen.
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Comparison of the zebrafish embryo toxicity assay and the general and behavioral embryo toxicity assay as new approach methods for chemical screening

Comparison of the zebrafish embryo toxicity assay and the general and behavioral embryo toxicity assay as new approach methods for chemical screening

distance travelled in 30 min under lighted conditions for living larvae at each exposure concentration was compared to vehicle controls using a one-way ANOVA followed by a Dunnett’s mul[r]

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