Expression pattern of cytosolic glutathione peroxidase (cGPx) mRNA during mouse embryogenesis

Abstract

The selenoprotein cytosolic glutathione peroxidase (cGPx) is ubiquitously distributed in a variety of organs, and its primary function is to protect oxidative damage. To investigate the spatial and temporal expression pattern of cGPx mRNA in embryogenesis, as this has not been studied before, reverse transcription-polymerase chain reaction (RT-PCR) was carried out in a thermal cycler using mouse-specific cGPx primers, and in situ hybridization was performed in whole embryos or embryonic tissues using digoxigenin-labeled mouse cGPx riboprobes. Expression of cGPx mRNA was detected in all the embryos retrieved from embryonic days (EDs) 7.5 to 18.5. On EDs 10.5-12.5, cGPx mRNA was highly expressed in the margin of forelimb and hindlimb buds and dorsally in the cranial neural tube, including the telencephalon, diencephalon, and hindbrain neural tube. On ED 13.5, cGPx mRNA was accumulated especially in vibrissae, forelimb and hindlimb plates, tail, and spinal cord. On EDs 14.5-16.5, cGPx mRNA was found in the developing brain, Rathke's pouch, thymus, lung, and liver. On ED 17.5, the expression of cGPx mRNA was apparent in various tissues such as brain, submandibular gland, vibrissae, heart, lung, liver, stomach, intestine, pancreas, skin, and kidney. In particular, cGPx mRNA was greatly expressed in epithelial linings and metabolically active sites such as whisker follicles, alveolar epithelium of lung, surface epithelium and glandular region of stomach, skin epithelium, and cortex and tubules of kidney. Overall results indicate that cGPx mRNA is expressed in developing embryos, cell-specifically and tissue-specifically, suggesting that cGPx may function to protect the embryo against reactive oxygen species and/or hydroperoxides massively produced by the intracellular or extracellular environment.

Comparative Analysis of Selenocysteine Machinery and Selenoproteome Gene Expression in Mouse Brain Identifies Neurons as Key Functional Sites of Selenium in Mammals

“…Gene targeting of Dio3 disrupted normal thyroid hormone signaling in the hypothalamus, but is probably not required for neuronal function in general (60). The best studied selenoprotein in the brain is probably GPx1 (61). Genetic inactivation of GPx1 increased susceptibility of rodents to neurodegenerative disease, and overexpression of GPx1 mitigated resulting damage (19).…”

Effects of Ginsenosides on Organogenesis and Expression of Glutathione Peroxidase Genes in Cultured Rat Embryos

“…Growth and development of rat embryos exposed to ginsenoside Rc on embryonic day 9.5 for 48 h in vitro protecting the animal against ROS-inducing radiation and can be applied to therapeutic remedies for a variety of ROS-associated diseases [36]. In our previous study, cGPx mRNA was shown to be expressed during mouse embryogenesis, distributed in specific cells and organs, and to be abundantly expressed in active differentiation sites [37]. The mRNA of phGPx is expressed ubiquitously during embryogenesis.…”

Spatiotemporal expression of the selenoprotein P genein postimplantational mouse embryos

“…Recently, we showed that antioxidant enzymes, including GPx1 and superoxide dismutase 1, were expressed throughout all mouse embryonic stages (Baek et al, 2005;Yon et al, 2008).…”

“…The spatial expression patterns were determined by whole mount in situ hybridization (Baek et al, 2005;Yon et al, 2008) using a DIG-labelled antisense probe. An antisense probe for the in situ hybridization was transcribed with T7 from the full length cDNA in the original pGEM-T vector digested with Spe I (sense: SP6).…”

“…For sections, mouse embryos (E 13.5-18.5) were embedded in paraplast and sectioned. In situ hybridization for tissue sections was conducted as previously described protocol (Baek et al, 2005;Yon et al, 2008).…”