Regulation of Gene Expression by SAR of Silkworm Attacus ricini rRNA Gene.
The 1 kb scaffold-attachment region (SAR) at 5' non-transcription region of rRNA gene of silkworm Attacus ricini was cloned into eukaryotic expression vector pLu, which contained luciferase report gene and neo(R) selecting marker. After transfection of constructs into NIH3T3 cell line by using cation liposome, the luciferase activity was monitored to check the SAR's function. The results demonstrated that the SAR could enhance gene expression up to 15-fold in stable transformed cells, but no obvious gene expression was observed in transient transfection. Its effect on gene expression appeared to requirechromosomal integration. Southwestern blotting experiments showed that SAR specifically bound to nuclear matrix proteins of NIH3T3 cells. The binding with nuclear matrix may be necessary for SAR function of transcriptional enhancement.
Wu
Zhen-Yu
ZY
Shanghai Institute of Biochemistry, the Chinese Academy of Sciences the Open Lab of Molecular Cell Biology, the Chinese Academy of Sciences, Shanghai 200031, China. mjzhao@sunm.shcnc.ac.cn
Zhao
Mu-Jun
MJ
Li
Zai-Ping
ZP