Homocysteine-induced neural tube defects in chick embryos via oxidative stress and DNA methylation associated transcriptional down-regulation of miR-124.

Although moderate homocysteine (HCY) elevation is associated with neural tube defects (NTDs), the underlying mechanisms have not been elucidated. In this study, we aimed to investigate that whether HCY-induced NTDs were associated with oxidative stress and methyl metabolism in chick embryos. The potential role of miR-124 in neurogenesis was also investigated.

The CXCL12-CXCR4 signaling promotes oocyte maturation by regulating cumulus expansion in sheep.

Gonadotropins and growth factors synergistically regulate folliculogenesis and oocyte development. C-X-C motif chemokine 12 (CXCL12) and its receptor CXCR4 are expressed in ovaries of sheep, cattle and other species, however, roles of this multifunctional signal axis in oocyte maturation are not defined. Using sheep as a model, we examined the expression patterns and functions of the CXCL12-CXCR4 axis during oocyte maturation.

Effects of choline on sodium arsenite-induced neural tube defects in chick embryos.

Arsenic passes through the placenta and accumulates in the neuroepithelium of embryo, whereby inducing congenital malformations such as neural tube defects (NTDs) in animals. Choline (CHO), a methyl-rich nutrient, functions as a methyl donor to participate in methyl group metabolism. Arsenic methylation has been regarded as a detoxification process and choline (CHO) is the major source of methyl-groups.

Oxidative stress is implicated in arsenic-induced neural tube defects in chick embryos.

The potential of arsenic to induce neural tube defects (NTDs) remains a topic of controversy. In our previous study, oxidative stress and altered DNA methylation were observed in arsenic-exposed animal models. However, the correlation between these conditions was not fully understood.

WITHDRAWN: Effects of choline on sodium arsenite-induced neural tube defects in chick embryos.

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.

Protective effects of N-acetylcysteine on homocysteine induced injury in chick embryos.

Protective effects of N-acetylcysteine (NAC) on homocysteine (Hcy)-induced injury have been reported in vitro. However, it is not known whether NAC has a similar effect in Hcy-induced injury during embryonic development. In this study, we tested the hypothesis that exogenous NAC can attenuate Hcy-induced injury in chick embryos.

Genome-scale mutagenesis and phenotypic characterization of two-component signal transduction systems in Xanthomonas campestris pv. campestris ATCC 33913.

The gram-negative bacterium Xanthomonas campestris pv. campestris is the causal agent of black rot disease of cruciferous plants. Its genome encodes a large repertoire of two-component signal transduction systems (TCSTSs), which consist of histidine kinases and response regulators (RR) to monitor and respond to environmental stimuli.

Two-component signal transduction systems of Xanthomonas spp.: a lesson from genomics.

The two-component signal transduction systems (TCSTSs), consisting of a histidine kinase sensor (HK) and a response regulator (RR), are the dominant molecular mechanisms by which prokaryotes sense and respond to environmental stimuli. Genomes of Xanthomonas generally contain a large repertoire of TCSTS genes (approximately 92 to 121 for each genome), which encode diverse structural groups of HKs and RRs. Among them, although a core set of 70 TCSTS genes (about two-thirds in total) which accumulates point mutations with a slow rate are shared by these genomes, the other genes, especially hybrid HKs, experienced extensive genetic recombination, including genomic rearrangement, gene duplication, addition or deletion, and fusion or fission.