人Elp3蛋白(human Elongator protein 3,hElp3)是组蛋白乙酰转移酶(Histone acetyltranferase,HAT)Elongator复合物的催化亚基,可参与组蛋白乙酰化修饰与基因转录延伸,其功能异常与人类多种疾病相关.目前对其羧基末端高度保守的第二功...人Elp3蛋白(human Elongator protein 3,hElp3)是组蛋白乙酰转移酶(Histone acetyltranferase,HAT)Elongator复合物的催化亚基,可参与组蛋白乙酰化修饰与基因转录延伸,其功能异常与人类多种疾病相关.目前对其羧基末端高度保守的第二功能域研究较少.以pYES2hElp3质粒为模板,PCR获hElp3基因全长,插入改造的毕赤酵母表达载体pPIC9KH,转化巴斯德毕赤酵母菌GS115菌株.经表型鉴定、PCR分析和G418筛选得到Mut+型多拷贝整合菌.0.5%的甲醇诱导hElp3高效分泌表达,Ni-NTA纯化及Western印迹证实获目的蛋白.OPA法测得其拥有良好的HAT活性,为体外测定其第二结构域是否拥有催化活性奠定了基础,对筛选抑制其HAT活性的小分子药物用于疾病治疗研究至关重要.展开更多
Autophagy is responsible for maintaining fundamental cellular homeostasis and is,therefore,essential for diverse development processes.This study reported that PoElp3,the putative catalytic subunit of Elongator comple...Autophagy is responsible for maintaining fundamental cellular homeostasis and is,therefore,essential for diverse development processes.This study reported that PoElp3,the putative catalytic subunit of Elongator complex,is involved in the maintenance of autophagy homeostasis to facilitate asexual development and pathogenicity in the rice blast fungus Pyricularia oryzae.It was found that the ΔPoelp3 strains were defective in vegetative growth,conidiation,stress response,and pathogenicity.The mutants exhibited hyper-activated autophagy in the vegetative hyphae under both nutrient-rich and nutrient-deficient conditions.The hyper-activation of autophagy possibly suppressed the production of vegetative hyphae in the ΔPoelp3 strains.Moreover,the ΔPoelp3 strains were found to be more sensitive to rapamycin during vegetative-and invasive-hyphal growth but have no effect on Target-of-Rapamycin(TOR)signaling inhibition.Taken together,these results demonstrated that PoElp3 is involved in asexual development and pathogenicity by regulating autophagy in the rice blast fungus.展开更多
Cell migration is a finely tuned biological process that often involves epithelial-mesenchymal transition(EMT).EMT is typically characterized by the upregulation of mesenchymal markers such as Snail1.This process has ...Cell migration is a finely tuned biological process that often involves epithelial-mesenchymal transition(EMT).EMT is typically characterized by the upregulation of mesenchymal markers such as Snail1.This process has been shown to be of critical importance to normal developmental processes,including neural crest migration and invasion.Interestingly,similar mechanisms are utilized in disease processes,such as tumor metastasis and migration.Notably,EMT and EMT-like processes confer tumor cells with the ability to migrate,invade,and adopt stem cell-like properties that largely account for immunosuppression and tumor recurrence.Therefore,identifying sensitive EMT markers may contribute to cancer prognosis and diagnosis in many facets.Previously,we showed that Elp3 plays an essential role during neural crest migration by stabilizing Snail1.In the current study,we further elucidate the molecular mechanism underlying colorectal cancer migration.We found that mElp3 exerted an identical function to xElp3 in modulating neural crest migration,and both HAT and SAM domains are imperative during this migratory process.Interestingly,overexpression of mElp3 in SW480 cells promoted cell migration and invasion,and we further showed that Elp3 stabilized Snail1 requiring integrity of both SAM and HAT domains.Our findings warrant further exploration of the specific target of Elp3 in cancer cells.展开更多
ELP3,the catalytic subunit of the Elongator complex,is an acetyltransferase and associated with tumor progression.However,the detail of ELP3 oncogenic function remains largely unclear.Here,we found that ELP3 stabilize...ELP3,the catalytic subunit of the Elongator complex,is an acetyltransferase and associated with tumor progression.However,the detail of ELP3 oncogenic function remains largely unclear.Here,we found that ELP3 stabilizes c-Myc to promote tumorigenesis in an acetyltransferase-independent manner.Mechanistically,ELP3 competes with the E3-ligase FBXW7βfor c-Myc binding,resulting in the inhibition of FBXW7β-mediated ubiquitination and proteasomal degradation of c-Myc.ELP3 knockdown diminishes glycolysis and glutaminolysis and dramatically retards cell proliferation and xenograft growth by downregulating c-Myc,and such effects are rescued by the reconstitution of c-Myc expression.Moreover,ELP3 and c-Myc were found overexpressed with a positive correlation in colorectal cancer and hepatocellular carcinoma.Taken together,we elucidate a new function of ELP3 in promoting tumorigenesis by stabilizing c-Myc,suggesting that inhibition of ELP3 is a potential strategy for treating c-Myc-driven carcinomas.展开更多
酵母Elp3（Yeast elongation protein 3,yElp3）是组蛋白乙酰转移酶复合物Elongator的催化亚基,通过组蛋白乙酰化参与基因转录延伸。近来证实胞质中也存在的Elp3还参与胞外分泌、tRNA修饰等重要生物学过程。为深入研究Elp3的复杂功能,PC...酵母Elp3（Yeast elongation protein 3,yElp3）是组蛋白乙酰转移酶复合物Elongator的催化亚基,通过组蛋白乙酰化参与基因转录延伸。近来证实胞质中也存在的Elp3还参与胞外分泌、tRNA修饰等重要生物学过程。为深入研究Elp3的复杂功能,PCR法克隆pYES2-yElp3质粒中编码yElp3N末端亲水区段（22~94aa）,构建原核表达载体pMXB10-yElp3-219,经IPTG诱导表达和几丁质柱纯化后免疫兔制备多克隆抗体。ELISA检测显示该抗体有较高的效价（不低于1：2500）,免疫印迹结果表明该抗体可特异性识别表达纯化及酵母细胞中的Elp3蛋白,运用该抗体进行的染色质免疫沉淀揭示转入elp3？菌株的酵母/人融合的yhElp3之所以可补偿突变株的基因表达延迟缺陷,是因其直接参与SSA3基因的转录延伸。展开更多
文摘人Elp3蛋白(human Elongator protein 3,hElp3)是组蛋白乙酰转移酶(Histone acetyltranferase,HAT)Elongator复合物的催化亚基,可参与组蛋白乙酰化修饰与基因转录延伸,其功能异常与人类多种疾病相关.目前对其羧基末端高度保守的第二功能域研究较少.以pYES2hElp3质粒为模板,PCR获hElp3基因全长,插入改造的毕赤酵母表达载体pPIC9KH,转化巴斯德毕赤酵母菌GS115菌株.经表型鉴定、PCR分析和G418筛选得到Mut+型多拷贝整合菌.0.5%的甲醇诱导hElp3高效分泌表达,Ni-NTA纯化及Western印迹证实获目的蛋白.OPA法测得其拥有良好的HAT活性,为体外测定其第二结构域是否拥有催化活性奠定了基础,对筛选抑制其HAT活性的小分子药物用于疾病治疗研究至关重要.
基金supported by grants from the National Natural Science Foundation of China(31770156 and 2016YFD0300700)the Innovative Research Funding of FAFU,China(CXZX2018051 and CXZX2018052)。
文摘Autophagy is responsible for maintaining fundamental cellular homeostasis and is,therefore,essential for diverse development processes.This study reported that PoElp3,the putative catalytic subunit of Elongator complex,is involved in the maintenance of autophagy homeostasis to facilitate asexual development and pathogenicity in the rice blast fungus Pyricularia oryzae.It was found that the ΔPoelp3 strains were defective in vegetative growth,conidiation,stress response,and pathogenicity.The mutants exhibited hyper-activated autophagy in the vegetative hyphae under both nutrient-rich and nutrient-deficient conditions.The hyper-activation of autophagy possibly suppressed the production of vegetative hyphae in the ΔPoelp3 strains.Moreover,the ΔPoelp3 strains were found to be more sensitive to rapamycin during vegetative-and invasive-hyphal growth but have no effect on Target-of-Rapamycin(TOR)signaling inhibition.Taken together,these results demonstrated that PoElp3 is involved in asexual development and pathogenicity by regulating autophagy in the rice blast fungus.
基金supported by the National Natural Science Foundation of China(Grant Nos.81760503 and 81760660)the Applied Basic Research Key Project of Yunnan(Grant Nos.2018FE001(-318)and 2018FE001(-123))the Yunnan Health Science and Technology Plan Projects(Grant No.2016NS207).
文摘Cell migration is a finely tuned biological process that often involves epithelial-mesenchymal transition(EMT).EMT is typically characterized by the upregulation of mesenchymal markers such as Snail1.This process has been shown to be of critical importance to normal developmental processes,including neural crest migration and invasion.Interestingly,similar mechanisms are utilized in disease processes,such as tumor metastasis and migration.Notably,EMT and EMT-like processes confer tumor cells with the ability to migrate,invade,and adopt stem cell-like properties that largely account for immunosuppression and tumor recurrence.Therefore,identifying sensitive EMT markers may contribute to cancer prognosis and diagnosis in many facets.Previously,we showed that Elp3 plays an essential role during neural crest migration by stabilizing Snail1.In the current study,we further elucidate the molecular mechanism underlying colorectal cancer migration.We found that mElp3 exerted an identical function to xElp3 in modulating neural crest migration,and both HAT and SAM domains are imperative during this migratory process.Interestingly,overexpression of mElp3 in SW480 cells promoted cell migration and invasion,and we further showed that Elp3 stabilized Snail1 requiring integrity of both SAM and HAT domains.Our findings warrant further exploration of the specific target of Elp3 in cancer cells.
基金supported by grants from China Postdoctoral Science Foundation(2022M712672)the National Natural Science Foundation of China(U21A20373 and 32070749).
文摘ELP3,the catalytic subunit of the Elongator complex,is an acetyltransferase and associated with tumor progression.However,the detail of ELP3 oncogenic function remains largely unclear.Here,we found that ELP3 stabilizes c-Myc to promote tumorigenesis in an acetyltransferase-independent manner.Mechanistically,ELP3 competes with the E3-ligase FBXW7βfor c-Myc binding,resulting in the inhibition of FBXW7β-mediated ubiquitination and proteasomal degradation of c-Myc.ELP3 knockdown diminishes glycolysis and glutaminolysis and dramatically retards cell proliferation and xenograft growth by downregulating c-Myc,and such effects are rescued by the reconstitution of c-Myc expression.Moreover,ELP3 and c-Myc were found overexpressed with a positive correlation in colorectal cancer and hepatocellular carcinoma.Taken together,we elucidate a new function of ELP3 in promoting tumorigenesis by stabilizing c-Myc,suggesting that inhibition of ELP3 is a potential strategy for treating c-Myc-driven carcinomas.
文摘酵母Elp3（Yeast elongation protein 3,yElp3）是组蛋白乙酰转移酶复合物Elongator的催化亚基,通过组蛋白乙酰化参与基因转录延伸。近来证实胞质中也存在的Elp3还参与胞外分泌、tRNA修饰等重要生物学过程。为深入研究Elp3的复杂功能,PCR法克隆pYES2-yElp3质粒中编码yElp3N末端亲水区段（22~94aa）,构建原核表达载体pMXB10-yElp3-219,经IPTG诱导表达和几丁质柱纯化后免疫兔制备多克隆抗体。ELISA检测显示该抗体有较高的效价（不低于1：2500）,免疫印迹结果表明该抗体可特异性识别表达纯化及酵母细胞中的Elp3蛋白,运用该抗体进行的染色质免疫沉淀揭示转入elp3？菌株的酵母/人融合的yhElp3之所以可补偿突变株的基因表达延迟缺陷,是因其直接参与SSA3基因的转录延伸。
