[Sudy on the activation of early growth response factor-1 by silica dioxide and its signal pathway].
OBJECTIVE
To discuss the role of early growth response factor (Egr)-1 and it's upstream signaling pathway in the development of silicosis.


METHODS
The expression and localization of Egr-1 were analyzed by immunofluorescence and in-situ hybridization. The activity of Egr-1 was observed in treated cells by using a reporter plasmid and EMSA, the activity of ERK1/2 in RAW264.7 incubated with SiO(2) by using a kinase assay, and further by using a kinase inhibitor assay to investigate the role of upstream kinase in the signal pathway of the activation of Egr-1.


RESULTS
The obvious increase of expression and transcription of Egr-1 was observed shortly after being treated by silica and its activity increased abruptly. There was an increase of the activity of ERK1/2 in RAW264.7 cells treated, which reached a peak at 30 minutes. The expression and transcription of Egr-1 decreased maniferstly after using kinase inhibitors.


CONCLUSIONS
Egr-1 expression can be induced by silica dioxide in RAW264.7 cells, and the ERK1/2, p38 kinases may take part in this process which suggest the pathway of SiO(2), ERK1/2, p38 and Egr-1 may play an important role in the development of silicosis.
Chu
Ling
L
Department of pathology, Xiangya Medical School, Central South University, Changsha 410078, China.
Jin
Zhong-yuan
ZY
Jiang
Hai-ying
HY
Hu
Yong-bin
YB
Zeng
Qing-fu
QF
D000818:Animals; D002070:Butadienes / Q000494:pharmacology; D002478:Cells, Cultured; D051766:Early Growth Response Protein 1 / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005786:Gene Expression Regulation; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009570:Nitriles / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D015398:Signal Transduction; D012822:Silicon Dioxide / Q000494:pharmacology*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
D002070:Butadienes; C497325:EGR1 protein, human; D051766:Early Growth Response Protein 1; D004791:Enzyme Inhibitors; D009570:Nitriles; D012333:RNA, Messenger; C113580:U 0126; D012822:Silicon Dioxide; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D048051:p38 Mitogen-Activated Protein Kinases