Background The cellular repressor of ElA-stimulated genes(CREG) is a secreted glycoprotein that inhibits cell proliferation and/or enhances differentiation.CREG is widely expressed in adult tissues such as the brain,h...Background The cellular repressor of ElA-stimulated genes(CREG) is a secreted glycoprotein that inhibits cell proliferation and/or enhances differentiation.CREG is widely expressed in adult tissues such as the brain,heart, lungs,liver,intestines and kidneys in mice.We investigated the level of CREG expression during mouse embryogenesis and its distribution at 18.5 days post coitus(dpc).Methods Immunohistochemical staining with diaminobenzidine,western blotting and reverse transcription-polymerase chain reaction were used.Results CREG expression was rst detected in mouse embryos at 4.5 dpc.It was expressed at almost all stages up to 18.5 dpc.The level of CREG was found to increase gradually and was highest at 18.5 dpc.Western blotting showed that the CREG protein was expressed at higher levels in the brain,heart,intestines and kidneys than in the lungs and liver at 18.5 dpc.In 9.5 dpc embryos,CREG was expressed only in the endothelial cells of blood vessels,after the vascular lumen had formed.With advanced differentiation, vascular smooth muscle cells developed in the embryonic vascular structures;the expression of smooth muscle a-actin protein and CREG were positive and increased gradually in 10.5 dpc embryonic vessels.CREG expression in the embryonic blood vessels peaked at 15.5 dpc and was reduced slightly at 18.5 dpc.Conclusions These results indicate that CREG is expressed during mouse embryogenesis and might participate in the differentiation of these organs during embryogenesis.展开更多
文摘Background The cellular repressor of ElA-stimulated genes(CREG) is a secreted glycoprotein that inhibits cell proliferation and/or enhances differentiation.CREG is widely expressed in adult tissues such as the brain,heart, lungs,liver,intestines and kidneys in mice.We investigated the level of CREG expression during mouse embryogenesis and its distribution at 18.5 days post coitus(dpc).Methods Immunohistochemical staining with diaminobenzidine,western blotting and reverse transcription-polymerase chain reaction were used.Results CREG expression was rst detected in mouse embryos at 4.5 dpc.It was expressed at almost all stages up to 18.5 dpc.The level of CREG was found to increase gradually and was highest at 18.5 dpc.Western blotting showed that the CREG protein was expressed at higher levels in the brain,heart,intestines and kidneys than in the lungs and liver at 18.5 dpc.In 9.5 dpc embryos,CREG was expressed only in the endothelial cells of blood vessels,after the vascular lumen had formed.With advanced differentiation, vascular smooth muscle cells developed in the embryonic vascular structures;the expression of smooth muscle a-actin protein and CREG were positive and increased gradually in 10.5 dpc embryonic vessels.CREG expression in the embryonic blood vessels peaked at 15.5 dpc and was reduced slightly at 18.5 dpc.Conclusions These results indicate that CREG is expressed during mouse embryogenesis and might participate in the differentiation of these organs during embryogenesis.
