Objective:Epidermal growth factor receptor variant III(EGFRvIII)is a constitutively-activated mutation of EGFR that contributes to the malignant progression of glioblastoma multiforme(GBM).Temozolomide(TMZ)is a standa...Objective:Epidermal growth factor receptor variant III(EGFRvIII)is a constitutively-activated mutation of EGFR that contributes to the malignant progression of glioblastoma multiforme(GBM).Temozolomide(TMZ)is a standard chemotherapeutic for GBM,but TMZ treatment benefits are compromised by chemoresistance.This study aimed to elucidate the crucial mechanisms leading to EGFRvIII and TMZ resistance.Methods:CRISPR-Cas13a single-cell RNA-seq was performed to thoroughly mine EGFRvIII function in GBM.Western blot,realtime PCR,flow cytometry,and immunofluorescence were used to determine the chemoresistance role of E2F1 and RAD51-associated protein 1(RAD51AP1).Results:Bioinformatic analysis identified E2F1 as the key transcription factor in EGFRvIII-positive living cells.Bulk RNA-seq analysis revealed that E2F1 is a crucial transcription factor under TMZ treatment.Western blot suggested enhanced expression of E2F1 in EGFRvIII-positive and TMZ-treated glioma cells.Knockdown of E2F1 increased sensitivity to TMZ.Venn diagram profiling showed that RAD51AP1 is positively correlated with E2F1,mediates TMZ resistance,and has a potential E2F1 binding site on the promoter.Knockdown of RAD51AP1 enhanced the sensitivity of TMZ;however,overexpression of RAD51AP1 was not sufficient to cause chemotherapy resistance in glioma cells.Furthermore,RAD51AP1 did not impact TMZ sensitivity in GBM cells with high O6-methylguanine-DNA methyltransferase(MGMT)expression.The level of RAD51AP1 expression correlated with the survival rate in MGMT-methylated,but not MGMT-unmethylated TMZ-treated GBM patients.Conclusions:Our results suggest that E2F1 is a key transcription factor in EGFRvIII-positive glioma cells and quickly responds to TMZ treatment.RAD51AP1 was shown to be upregulated by E2F1 for DNA double strand break repair.Targeting RAD51AP1 could facilitate achieving an ideal therapeutic effect in MGMT-methylated GBM cells.展开更多
AP2/ERF(APETALA2/ethylene-responsive factor)是植物中最大的转录因子家族之一,至少含有1个由60~70个高度保守的氨基酸组成的特有的AP2结构域,根据AP2结构域数量和相似性可划分为5个亚家族:AP2(APETALA2)、DREB(Dehydration-responsiv...AP2/ERF(APETALA2/ethylene-responsive factor)是植物中最大的转录因子家族之一,至少含有1个由60~70个高度保守的氨基酸组成的特有的AP2结构域,根据AP2结构域数量和相似性可划分为5个亚家族:AP2(APETALA2)、DREB(Dehydration-responsive element binding proteins)、ERF(Ethylene-responsive factor)、RAV(Related to AB13/VP)和Soloist。AP2/ERF转录因子通过AP2结构域中的YRG和RAYD保守元件与靶基因结合,实现对相关基因的转录调控功能。目前,AP2/ERF已成为研究植物抗逆机制和活性成分生物合成的热点候选基因,越来越多植物AP2/ERF家族及其成员被报道。本研究对近年来有关AP2/ERF家族的最新研究成果进行了总结,综述了AP2/ERF家族转录因子的结构特征与分类,重点介绍了该类转录因子调控植物次生代谢产物的合成以及参与生物、非生物胁迫应答等方面的研究进展,并展望了AP2/ERF转录因子可能的研究热点和领域,以期为今后进一步挖掘和利用该类转录因子基因进行植物遗传改良以及种质创新提供参考。展开更多
基金supported by the Science and Technology Project of Tianjin Municipal Health Commission(Grant Nos.TJWJ2022MS003 and TJWJ2021ZD008)the Tianjin Science and Technology Plan Project(Grant Nos.21JCYBJC01520 and 20JCYBJC01070)。
文摘Objective:Epidermal growth factor receptor variant III(EGFRvIII)is a constitutively-activated mutation of EGFR that contributes to the malignant progression of glioblastoma multiforme(GBM).Temozolomide(TMZ)is a standard chemotherapeutic for GBM,but TMZ treatment benefits are compromised by chemoresistance.This study aimed to elucidate the crucial mechanisms leading to EGFRvIII and TMZ resistance.Methods:CRISPR-Cas13a single-cell RNA-seq was performed to thoroughly mine EGFRvIII function in GBM.Western blot,realtime PCR,flow cytometry,and immunofluorescence were used to determine the chemoresistance role of E2F1 and RAD51-associated protein 1(RAD51AP1).Results:Bioinformatic analysis identified E2F1 as the key transcription factor in EGFRvIII-positive living cells.Bulk RNA-seq analysis revealed that E2F1 is a crucial transcription factor under TMZ treatment.Western blot suggested enhanced expression of E2F1 in EGFRvIII-positive and TMZ-treated glioma cells.Knockdown of E2F1 increased sensitivity to TMZ.Venn diagram profiling showed that RAD51AP1 is positively correlated with E2F1,mediates TMZ resistance,and has a potential E2F1 binding site on the promoter.Knockdown of RAD51AP1 enhanced the sensitivity of TMZ;however,overexpression of RAD51AP1 was not sufficient to cause chemotherapy resistance in glioma cells.Furthermore,RAD51AP1 did not impact TMZ sensitivity in GBM cells with high O6-methylguanine-DNA methyltransferase(MGMT)expression.The level of RAD51AP1 expression correlated with the survival rate in MGMT-methylated,but not MGMT-unmethylated TMZ-treated GBM patients.Conclusions:Our results suggest that E2F1 is a key transcription factor in EGFRvIII-positive glioma cells and quickly responds to TMZ treatment.RAD51AP1 was shown to be upregulated by E2F1 for DNA double strand break repair.Targeting RAD51AP1 could facilitate achieving an ideal therapeutic effect in MGMT-methylated GBM cells.
文摘AP2/ERF(APETALA2/ethylene-responsive factor)是植物中最大的转录因子家族之一,至少含有1个由60~70个高度保守的氨基酸组成的特有的AP2结构域,根据AP2结构域数量和相似性可划分为5个亚家族:AP2(APETALA2)、DREB(Dehydration-responsive element binding proteins)、ERF(Ethylene-responsive factor)、RAV(Related to AB13/VP)和Soloist。AP2/ERF转录因子通过AP2结构域中的YRG和RAYD保守元件与靶基因结合,实现对相关基因的转录调控功能。目前,AP2/ERF已成为研究植物抗逆机制和活性成分生物合成的热点候选基因,越来越多植物AP2/ERF家族及其成员被报道。本研究对近年来有关AP2/ERF家族的最新研究成果进行了总结,综述了AP2/ERF家族转录因子的结构特征与分类,重点介绍了该类转录因子调控植物次生代谢产物的合成以及参与生物、非生物胁迫应答等方面的研究进展,并展望了AP2/ERF转录因子可能的研究热点和领域,以期为今后进一步挖掘和利用该类转录因子基因进行植物遗传改良以及种质创新提供参考。
