[Effects of LIMK2 RNA interference on the mechanosensitivity of c-fos gene in osteoblast].
OBJECTIVE
To study the effects of cytoskeleton reorganization inhibition with LIMK2 RNAi upon the mechanosensitivity of c-fos gene in osteoblast.


METHODS
Mouse primary osteoblast was treated with LIMK2 specific siRNA (RNAi Group), negative control siRNA (NC Group), and then were loaded or unloaded by fluid shear stress. Real-time PCR and immunofluorescence were used to detect the c-fos expression levels and statistics analysis was performed.


RESULTS
When the cytoskeleton reorganization was inhibited with RNAi only, the c-fos mRNA (0.0108 +/- 0.0074 and 0.0042 +/- 0.0018, t = -1.86, P > 0.05) and protein (121 +/- 7 and 119 +/- 6, t = -1.272, P > 0.05) expression levels of each unloaded group had no significant difference; Fluid shear stress could up-regulate the c-fos mRNA (0.2203 +/- 0.1532 vs 0.0042 +/- 0.0018, t = -707.35, P < 0.05)and protein (178 +/- 12 vs 119 +/- 6, t = -30.761, P < 0.05) expression; After the cytoskeleton reorganization was inhibited with RNAi, the c-fos mRNA (0.5280 +/- 0.0879 vs 0.2203 +/- 0.1532, t = -1007.00, P < 0.05) and protein (224 +/- 46 vs 178 +/- 12, t = -6.853, P < 0.05) expression induced by fluid shear stress had significant difference. Cytoskeleton reorganization inhibition with RNAi had synergistic effect upon the expression of c-fos mRNA (F = 84.388, P < 0.05) and protein (F = 42.409, P < 0.05) induced by fluid shear stress.


CONCLUSIONS
Using RNAi against LIMK2 to inhibit the cytoskeleton reorganization can promote the expression of c-fos gene and thus enhance the mechanosensitivity of c-fos gene in osteoblast.
Zhang
Yi-ping
YP
Department of Prosthodontics, Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China.
Qin
Feng
F
Wu
Chang-jing
CJ
Li
You-rui
YR
Chen
Rui
R
Shao
Min-feng
MF
Fu
Qiang
Q
D000818:Animals; D002478:Cells, Cultured; D003599:Cytoskeleton / Q000378:metabolism*; D015870:Gene Expression; D054461:Lim Kinases / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics*; D034622:RNA Interference; D034741:RNA, Small Interfering; D013314:Stress, Mechanical
D016760:Proto-Oncogene Proteins c-fos; D034741:RNA, Small Interfering; D054461:Lim Kinases; C095325:Limk2 protein, mouse