Biallelic inactivation of fumarate hydratase (FH) causes type 2 papillary renal cell carcinoma (PRCC2), uterine fibroids, and cutaneous leimyomas, a condition known as hereditary leiomyomatosis and renal cell cancer (...Biallelic inactivation of fumarate hydratase (FH) causes type 2 papillary renal cell carcinoma (PRCC2), uterine fibroids, and cutaneous leimyomas, a condition known as hereditary leiomyomatosis and renal cell cancer (HLRCC). The most direct effect of FH inactivation is intracellular fumarate accumulation. A majority of studies on FH inactivation over the past decade have focused on the theory that intracellular fumarate stabilizes hypoxia-inducible factor 1α (HIF1A) through competitive inhibition of HIF prolyl hydroxylases. Recently, a competing theory that intracellular fumarate activates nuclear factor (erythroid-derived 2)-like 2 (NRF2) through post-translational modification of its negative regulator. Kelch-like ECH-associated protein 1 (KEAP1) has emerged from a computational modeling study and mouse model studies. This review dissects the origin of these two governing theories and highlights the presence of chromatin-structure-regulated targets of transcription factors, which we refer to as "cryptic targets" of transcription factors. One such cryptic target is heme oxygenase I (HMOX1), the expression of which is known to be modulated by the gene product of SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily a, member 4 (SMARCA4, also known as BRG1).展开更多
It remains uncovered yet how the common gastric pathogen,Helicobacter pylori,survives through the acidic barrier and the immune response simultaneously in the stomach.Herein we report a unique GroES chaperonin that ef...It remains uncovered yet how the common gastric pathogen,Helicobacter pylori,survives through the acidic barrier and the immune response simultaneously in the stomach.Herein we report a unique GroES chaperonin that effectively inactivates Helicobacter pylori urease in Escherichia coli model.Such a function depends on the quaternary structure as well as the metal binding at the C terminus.Surprisingly,the C-terminal metal capacity seems not closely relevant to the apparent urease inactivation.Our findings have possibly revealed a survival strategy of Helicobacter pylori after its gastric localization.展开更多
文摘Biallelic inactivation of fumarate hydratase (FH) causes type 2 papillary renal cell carcinoma (PRCC2), uterine fibroids, and cutaneous leimyomas, a condition known as hereditary leiomyomatosis and renal cell cancer (HLRCC). The most direct effect of FH inactivation is intracellular fumarate accumulation. A majority of studies on FH inactivation over the past decade have focused on the theory that intracellular fumarate stabilizes hypoxia-inducible factor 1α (HIF1A) through competitive inhibition of HIF prolyl hydroxylases. Recently, a competing theory that intracellular fumarate activates nuclear factor (erythroid-derived 2)-like 2 (NRF2) through post-translational modification of its negative regulator. Kelch-like ECH-associated protein 1 (KEAP1) has emerged from a computational modeling study and mouse model studies. This review dissects the origin of these two governing theories and highlights the presence of chromatin-structure-regulated targets of transcription factors, which we refer to as "cryptic targets" of transcription factors. One such cryptic target is heme oxygenase I (HMOX1), the expression of which is known to be modulated by the gene product of SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily a, member 4 (SMARCA4, also known as BRG1).
基金supported by Research Grants Council of Hong Kong (HKU7042/07P,HKU7049/09P and HKU7046/12P)
文摘It remains uncovered yet how the common gastric pathogen,Helicobacter pylori,survives through the acidic barrier and the immune response simultaneously in the stomach.Herein we report a unique GroES chaperonin that effectively inactivates Helicobacter pylori urease in Escherichia coli model.Such a function depends on the quaternary structure as well as the metal binding at the C terminus.Surprisingly,the C-terminal metal capacity seems not closely relevant to the apparent urease inactivation.Our findings have possibly revealed a survival strategy of Helicobacter pylori after its gastric localization.
