Li-Jung Juan

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p53, the most commonly mutated gene in cancer cells, directs cell cycle arrest or induces programmed cell death (apoptosis) in response to stress. It has been demonstrated that p53 activity is up-regulated in part by posttranslational acetylation. In agreement with these observations, here we show that mammalian histone deacetylase (HDAC)-1, -2, and -3 are(More)
Hypermethylation-mediated tumor suppressor gene silencing plays a crucial role in tumorigenesis. Understanding its underlying mechanism is essential for cancer treatment. Previous studies on human N-alpha-acetyltransferase 10, NatA catalytic subunit (hNaa10p; also known as human arrest-defective 1 [hARD1]), have generated conflicting results with regard to(More)
Tumor suppressor gene silencing through cytosine methylation contributes to cancer formation. Whether DNA demethylation enzymes counteract this oncogenic effect is unknown. Here, we show that TET1, a dioxygenase involved in cytosine demethylation, is downregulated in prostate and breast cancer tissues. TET1 depletion facilitates cell invasion, tumor growth,(More)
In order to investigate the interrelated roles of nucleosome cores and histone H1 in transcription repression, we have employed a purified system to analyze the function of H1 in the repression of transcription factor binding to nucleosomes. H1 binding to nucleosome cores resulted in the repression of USF binding to nucleosomes. By contrast, H1 only(More)
The retinoblastoma binding protein RBP2 (KDM5A) is a histone demethylase that promotes gastric cancer cell growth and is enriched in drug-resistant lung cancer cells. In tumor-prone mice lacking the tumor suppressor gene RB or MEN1, genetic ablation of RBP2 can suppress tumor initiation, but the pathogenic breadth and mechanistic aspects of this effect(More)
Hepatitis delta virus (HDV) is a single-stranded RNA virus that encodes two viral nucleocapsid proteins named small and large form hepatitis delta antigen (S-HDAg and L-HDAg). The S-HDAg is essential for viral RNA replication while the L-HDAg is required for viral assembly. In this study, we demonstrated that HDAg are acetylated proteins. Metabolic labeling(More)
Facilitated, "cooperative" binding of GAL4-AH to nucleosomal DNA occurred in response to inhibition from the core histone amino termini. The binding of GAL4-AH (which contains the DNA-binding and dimerization domains of GAL4) to nucleosome cores containing multiple binding sites initiated at the end of a nucleosome core and proceeded in a cooperative manner(More)
Overexpression of DNA 5'-cytosine-methyltransferases (DNMT), which are enzymes that methylate the cytosine residue of CpGs, is involved in many cancers. However, the mechanism of DNMT overexpression remains unclear. Here, we showed that wild-type p53 negatively regulated DNMT1 expression by forming a complex with specificity protein 1 (Sp1) protein and(More)
Microenvironment plays an important role in cancer development. We have reported that the cancer-associated stromal cells exhibit phenotypic and functional changes compared to stromal cells neighboring to normal tissues. However, the molecular mechanisms as well as the maintenance of these changes remain elusive. Here we showed that through co-culture with(More)
Targeting of cellular histone acetyltransferases (HATs) by viral proteins is important in the development of virus-associated diseases. The immediate-early 2 protein (IE2) of human cytomegalovirus (HCMV) binds to the tumor suppressor, p53, and inactivates its functions by unknown mechanisms. Here, we show that IE2 binds to the HAT domain of the p53(More)