Cell polarization and asymmetric cell divisions play important roles during development in many multicellular eukaryotes. Fucoid algae have a long history as models for studying early developmental processes, probably because of the ease with which zygotes can be observed and manipulated in the laboratory. This review discusses cell polarization and asymmetric cell divisions in fucoid algal zyg...

Matured bovine oocytes and zygotes obtained by in vitro maturation and fertilization techniques (IVM and IVF) were cytogenetically prepared by using an improved method for chromosome preparations. The method, which involves use of trypsinizedhypotonic solution plus a vortex-agitated system and very cold two-step fixation process, contributes to weaken the zona pellucida and allows the swelling ...

Gene engineering for generating targeted mouse mutants is a key technology for biomedical research. Using TALENs as sequence-specific nucleases to induce targeted double-strand breaks, the mouse genome can be directly modified in zygotes in a single step without the need for embryonic stem cells. By embryo microinjection of TALEN mRNAs and targeting vectors, knockout and knock-in alleles can be...

Nuclear reprogramming, the conversion of the epigenome of a differentiated cell to one that is similar to the undifferentiated embryonic state, can be facilitated by several methods, such as nuclear transfer, cell fusion, use of embryonic stem cell extracts, and more recently, by the introduction of exogenous transcription factors. Amongst these various strategies, somatic cell nuclear transfer...

Crosses were made between haploid wild-type and suppressive petite strains of bakers' yeast to obtain zygotes for analysis of mitochondrial heterogeneity. Wild-type x petite zygotes contained about 40% noncristate mitochondria when immediate mating mixtures were examined. The frequency of defective mitochondria had decreased to an average of 9.2% in 1-week-old zygote isolate cultures, and to 4....

STUDY QUESTION What is the intracellular concentration of cryoprotectant (ICCP) in mouse zygotes during vitrification (VIT) and slow-freezing (SLF) cryopreservation procedures? SUMMARY ANSWER Contrary to common beliefs, it was observed that the ICCP in vitrified zygotes is lower than after SLF, although the solutions used in VIT contain higher concentrations of cryoprotectants (CPs). WHAT I...

The controlled release of well-defined radical species under mild conditions for subsequent use in selective reactions is an important and challenging task synthetic chemistry. We show here that simple bismuth amide [Bi(NAr2)3] readily aminyl radicals [NAr2]. at ambient temperature solution. These yield the corresponding hydrazines, Ar2N?NAr2, as a result highly N?N coupling. exploitation facil...

Transcription activator-like effector nuclease (TALEN) and zinc finger nuclease (ZFN) genome editing technology enables site directed engineering of the genome. Here we demonstrate for the first time that both TALEN and ZFN injected directly into pig zygotes can produce live genome edited pigs. Monoallelic as well as heterozygous and homozygous biallelic events were identified, significantly br...

studying crustal and upper mantel structures has been limited in the iranian plateau and there has been little work done in this field. in this paper we have a primary motive to map pn and sn velocities beneath most of the iranian plateau in order to test 3-d mantle models and to develop and test a method to produce pn and sn travel time correction surfaces that are the 3-d analogue of travel t...