Specific inhibition of gene expression using a stably integrated, inducible small‐interfering‐RNA vector

The c-Jun/Sp1 interaction is essential for growth factor- and phorbol 12-myristate 13-acetate (PMA)-induced genes expression, including human 12(S)-lipoxygenase, keratin 16, cytosolic phospholipase A2, p21WAF1/CIP1, and neuronal nicotinic acetylcholine receptor β4. Here, we examined the mechanism underlying the PMA-induced regulation on the interaction between c-Jun and Sp1. We found that treatment of cells with PMA induced a dephosphorylation at the C terminus of c-Jun at Ser-243 and a concomitant inhibition of PP2B by using PP2B small interfering RNA, resulting in reduction of PMA-induced gene expression as well as the c-Jun/Sp1 interaction. The c-Jun mutant TAM-67-3A, which contains three substitute alanines at Thr-231, Ser-243, and Ser-249 compared with TAM-67, binds more efficaciously with Sp1 and is about twice as efficacious as TAM-67 in inhibiting the PMA-induced activation of the 12(S)-lipoxygenase promoter. Importantly, PP2B not only dephosphorylates the c-Jun at Ser-243 but also interacts with c-Jun in PMA-treated cells. PMA stimulates the association of the PP2B/c-Jun/Sp1 complex with the promoter. These findings indicate the dephosphorylation of c-Jun C terminus is required for the c-Jun/Sp1 interaction and reveal that PP2B plays an important role in regulating c-Jun/Sp1 interaction in PMA-induced gene expression.

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49. Modulation of Gene Expression by Lentiviral-Mediated Delivery of Small Interfering RNA

Molecular Therapy ◽

10.1016/s1525-0016(16)40491-0 ◽

2003 ◽

Vol 7 (5) ◽

pp. S19

Keyword(s):

Gene Expression ◽

Small Interfering Rna ◽

Modulation Of Gene Expression ◽

Interfering Rna

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Inhibition of Hepatitis B virus gene expression by single and dual small interfering RNA treatment

Virus Research ◽

10.1016/j.virusres.2005.04.001 ◽

2005 ◽

Vol 112 (1-2) ◽

pp. 100-107 ◽

Cited By ~ 37

Author(s):

Kai-Lang Wu ◽

Xue Zhang ◽

Jianlin Zhang ◽

Yongbo Yang ◽

Yong-Xin Mu ◽

...

Keyword(s):

Gene Expression ◽

Hepatitis B Virus ◽

Hepatitis B ◽

Small Interfering Rna ◽

Virus Gene ◽

Virus Gene Expression ◽

B Virus ◽

Interfering Rna

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Down-regulation of Human DAB2IP Gene Expression Mediated by Polycomb Ezh2 Complex and Histone Deacetylase in Prostate Cancer

Journal of Biological Chemistry ◽

10.1074/jbc.m501379200 ◽

2005 ◽

Vol 280 (23) ◽

pp. 22437-22444 ◽

Cited By ~ 161

Author(s):

Hong Chen ◽

Szu-wei Tu ◽

Jer-Tsong Hsieh

Keyword(s):

Gene Expression ◽

Prostate Cancer ◽

Epithelial Cells ◽

Histone Deacetylase ◽

Promoter Region ◽

Small Interfering Rna ◽

Gene Promoter ◽

Down Regulation ◽

Ezh2 Expression ◽

Interfering Rna

Human DAB2IP (hDAB2IP), a novel GTPase-activating protein modulating the Ras-mediated signaling and tumor necrosis factor-mediated apoptosis, is a potent growth inhibitor in human prostate cancer (PCa). Loss of hDAB2IP expression in PCa is due to altered epigenetic regulation (i.e. DNA methylation and histone modification) of its promoter region. The elevated polycomb Ezh2, a histone methyltransferase, has been associated with PCa progression. In this study, we have demonstrated that an increased Ezh2 expression in normal prostatic epithelial cells can suppress hDAB2IP gene expression. In contrast, knocking down the endogenous Ezh2 levels in PCa by a specific small interfering RNA can increase hDAB2IP expression. The association of Ezh2 complex (including Eed and Suz12) with hDAB2IP gene promoter is also detected in PCa cells but not in normal prostatic epithelial cells. Increased Ezh2 expression in normal prostatic epithelial cells by cDNA transfection facilitates the recruitment of other components of Ezh2 complex to the hDAB2IP promoter region accompanied with the increased levels of methyl histone H3 (H3) and histone deacetylase (HDAC1). Consistently, data from PCa cells transfected with Ezh2 small interfering RNA demonstrated that reduced Ezh2 levels resulted in the dissociation of Ezh2 complex accompanied with decreased levels of both methyl H3 and HDAC1 from hDAB2IP gene promoter. We further unveiled that the methylation status of Lys-27 but not Lys-9 of H3 in hDAB2IP promoter region is consistent with the hDAB2IP levels in both normal prostatic epithelial cells and PCa cells. Together, we conclude that hDAB2IP gene is a target gene of Ezh2 in prostatic epithelium, which provides an underlying mechanism of the down-regulation of hDAB2IP gene in PCa.

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Knockdown of Survivin and Upregulation of p53 Gene Expression by Small Interfering RNA Induces Apoptosis in Human Gastric Carcinoma Cell Line SGC-823

Cancer Biotherapy & Radiopharmaceuticals ◽

10.1089/cbr.2008.0503 ◽

2008 ◽

Vol 23 (6) ◽

pp. 727-734 ◽

Cited By ~ 6

Author(s):

Yun-Hua Lu ◽

Kai Wang ◽

Rui He ◽

Tao Xi

Keyword(s):

Gene Expression ◽

Gastric Carcinoma ◽

Cell Line ◽

Small Interfering Rna ◽

Carcinoma Cell ◽

P53 Gene ◽

Gastric Carcinoma Cell ◽

Gastric Carcinoma Cell Line ◽

Human Gastric Carcinoma ◽

Interfering Rna

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Protein Kinase C Alpha Acting Through Phorbol-12-Myristate 13-Acetate Regulates Nephronectin Gene Expression Via c-Jun and c-Fos Transcription Factors

10.21203/rs.3.rs-579583/v1 ◽

2021 ◽

Author(s):

Mitsuhiro Kinoshita ◽

Atsushi Yamada ◽

Kiyohito Sasa ◽

Kaori Ikezaki ◽

Tatsuo Shirota ◽

...

Keyword(s):

Gene Expression ◽

Protein Kinase C ◽

Protein Kinase ◽

Small Interfering Rna ◽

Matrix Protein ◽

Extracellular Matrix Protein ◽

Down Regulation ◽

Kinase C ◽

Interfering Rna ◽

Dose Dependent

Abstract Nephronectin (Npnt) is an extracellular matrix protein and ligand of integrin α8β1 known to promote differentiation of osteoblasts. A search for factors that regulate Npnt gene expression in osteoblasts revealed that phorbol 12-myristate 13-acetate (PMA), which activates protein kinase C (PKC), had a strong effect to suppress that expression. Research was then conducted to elucidate the signaling pathway responsible for regulation of Npnt gene expression by PMA in osteoblasts. Treatment of MC3T3-E1 cells with PMA suppressed cell differentiation and Npnt gene expression. Effects were noted at a low concentration of PMA, and were time- and dose-dependent. Furthermore, treatment with the PKC signal inhibitor Gö6983 inhibited down-regulation of Npnt expression, while transfection with small interfering RNA (siRNA) of PKCα, c-Jun, and c-Fos suppressed that down-regulation. The present results suggest regulation of Npnt gene expression via the PKCα and c-Jun/c-Fos pathway.

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