DHRS4L2非编码RNA调控CPNE6基因表达（英文）

DHRS4/NRDR基因编码一种属于SDR家族的酶,在维甲酸合成、类固醇代谢和苯甲基代谢中发挥生物合成催化作用.DHRS4基因定位于14q11.2,有两个相似的拷贝基因,分别为DHRS4L2和DHRS4L1.我们前期发现了DHRS4L2基因一个上游转录起始位点,命名为DHRS4L2-Ea.在本研究中,我们用RT-PCR和双脱氧测序法发现一个新的从DHRS4L2-Ea转录的选择性剪接亚型DHRS4L2-900a(KC237374).同时RT-PCR结果显示在SK-N-SH细胞DHRS4L2-Ea选择性剪接亚型中DHRS4L2-iso(AY616183)表达最多,为主要亚型.在SK-N-SH细胞过表达DHRS4L2-800a(AY920361)使DHRS4L2-Ea基因下游CPNE6 mRNA表达下调.在HeLa细胞过表达DHRS4L2-800a(AY920361)或DHRS4L2-900a(KC237374)进一步表明DHRS4L2-Ea抑制CPNE6表达的作用.定量PCR结果显示si-RNA抑制DHRS4L2-Ea表达使CPNE6 mRNA表达上调.亚硫酸盐测序结果显示在SK-N-SH转染DHRS4L2-800a(AY920361)的样本中CPNE6基因DNA CpG甲基化增加.综上所述,本研究揭示DHRS4L2表达的非编码RNA抑制其下游基因CPNE6的表达.     

反义核酸真核表达载体的构建及其对重组HeLa细胞H654中IVS-2-654C→T突变β-珠蛋白基因剪接缺陷的抑制作用

在原工作的基础上 ,将非细胞系统中证明有效的反义片段通过高效真核表达载体 pCDNA3导入能稳定表达IVS -2 -6 5 4C→T突变 β 珠蛋白基因的重组HeLa细胞 (H6 5 4)中 .结果显示 ,转染后第 3天 ,H6 5 4细胞内正常剪接的β -珠蛋白mRNA水平 ( β/( β + β *) )明显上升 ,从 0 0 7上升到 0 2 2 ,并维持到第 1 5天 ,最高达到0 43.实验表明构建的反义片段真核表达载体在细胞中能稳定转录反义RNA并有效抑制IVS -2 -6 5 4C→T突变β 珠蛋白基因的异常剪接 ,为开展反义核酸治疗剪接缺陷型遗传性疾病提供了更直接的科学依据     

辐射诱导转录子RIGb cDNA对HeLa细胞增殖的抑制作用

核酸序列同源性分析和RT -PCR确定辐射诱导转录子RIGb是染色质重构基因CHD6表达的一个剪接转录子.Northern杂交结果表明,0 . 5Gyγ射线诱导RIGbmRNA表达增加,但4Gy大剂量照射对其表达无明显的影响.正常成人组织Northern杂交结果显示,RIGb基因在心脏、肝脏和睾丸中有高表达.细胞生长曲线分析结果表明,转染和稳定表达RIGb的人宫颈癌细胞(HeLa)的增殖生长受到明显抑制,细胞周期分析发现G1/S期阻滞.     

p16INK4a基因的功能及其调控

p16INK4a蛋白能抑制CDK4和CDK6的活性,使pRb处于非磷酸化或低磷酸化状态而能与转录因子E2Fs结合,从而抑制DNA 的合成,阻止细胞由G1期进入S期.p16INK4a的表达受Ets1和Ets2的正调控,受Bmi-1的负调控.p16INK4a基因缺失、突变、甲基化、RNA剪接加工错误可导致细胞周期失控和癌变.应用p16INK4a对某些肿瘤进行基因治疗的研究正在进行中.     

草菇葡萄糖‐6‐磷酸脱氢酶基因及其可变剪接体的克隆与表达量分析

葡萄糖-6-磷酸脱氢酶是戊糖磷酸途径的限速酶,影响着细胞生命活动所需要的NADPH的产生。本研究从草菇中克隆到该基因的2个转录本,并测定了它们在两个同核体和形成的异核体菌株中的表达量。结果表明,草菇葡萄糖-6-磷酸脱氢酶基因(g6pdh)的g DNA序列长1 954bp,有7个内含子,可产生两个转录本:一个是内含子全部剪切的转录本(g6pdh ID),编码515个氨基酸且有完整结构域的蛋白质;另一个是第5个内含子保留的可变剪接变体(g6pdh IR),预测编码316个氨基酸但没有完整结构域的蛋白质。定量PCR结果显示,可变剪接变体g6pdh IR在草菇同核体与异核体中的表达量均很低,因此转录本g6pdh ID为g6pdh基因的主要剪接体;并且g6pdh基因在生长旺盛的异核体中的表达量远远高于在生长较弱的两个同核体中的任何一个。研究结论说明,糖代谢活动的强弱与食用真菌的生长与发育有密切关系。     

转录因子HBP1调控H2O2诱导的骨肉瘤细胞生长阻滞过程

为探讨氧化应激对人骨肉瘤细胞增殖的影响及其作用机理,首先用H2O2处理U2OS细 胞,采用Western印迹和real-time PCR检测HMG盒转录因子1 (HBP1)及其下游靶基因 DNMT1和p16表达水平的变化. 用荧光素酶报告基因实验检测在H2O2诱导下, HBP1对于DNMT1 和p16启动子的影响. 用细胞增殖试验（BrdU掺入,细胞生长曲线）检测 H2O2对细胞增殖的影响以及HBP1的作用. 用衰老相关β半乳糖苷酶(SA-β-Gal)染色 检测在H2O2诱导的细胞衰老中HBP1所起的作用. Western 印迹, real-time PCR及荧光素酶报告基因实验结果显示,细胞经H2O2处理后,明显增高HBP1表达水平,转录抑制DNMT1的表达, 促进p16蛋白的表达. 细胞增殖实验结果显示, H2O2显著抑制了细胞的增殖,HBP1 knockdown可部分逆转这种抑制作用. SA-β-Gal染色实验说明, H2O2可诱导HBP1表达正常的U2OS细胞衰老,而HBP1 knockdown使这种促衰老作用减弱. 研究结果说明, H2O2可抑制人骨肉瘤细胞增殖,诱导细胞衰老. 其作用机制是通过上调转录因子HBP1的表达,转录抑制或促进其下游靶基因DNMT1或p16的表达来抑制细胞增殖,促进细胞衰老.     

用于前体mRNA剪接机制研究的小基因模型的建立和研究应用

建立可用于选择性前体mRNA剪接分析的小基因模型. 以人或小鼠基因组DNA为模板, 通过PCR扩增获得GluR-B, FGF-2R和Zis小基因片段, 并将其克隆至真核表达载体中, 构建了小基因的质粒. 在此基础上, 将上述3个小基因模型和剪接因子Tra2β1或Zis2表达质粒共转染HeLa细胞, 并用RT-PCR进行了被剪接的小基因产物的半定量检测. 结果表明, 这些小基因可用于细胞水平的基因剪接分析, 利用该技术平台, 发现了Zis2亚型可以促进Zis小基因选择性剪接.     

人肌原纤维生成调节因子-1的研究进展

人肌原纤维生成调节因子-1(myofibrillogenesis regulator 1, MR-1)是一个新近报道的人类功能基因,定位于2q35,mRNA全长755bp,编码一段142个氨基酸组成的蛋白质,在心肌、骨骼肌、肾和肝中高表达.该基因与稍迟报道的发作性非运动源性运动障碍(paroxysmal nonkinesigenic dyskinesia, PNKD)基因三条转录剪接异构体中最短的PNKD-3在定位和序列上几乎完全一致.较长的剪接异构体MR-1L(PNKD-1)只在中枢神经系统中特异性表达,位于该亚型1号外显子上的碱基突变是导致PNKD的直接原因;MR-1S(PNKD-3)则被发现参与了心肌肥大的发生,其机制可能与调节肌肉收缩相关装置有关.     

lncRNA ROR1-AS1通过靶向miR-758-3p调控神经母细胞瘤SK-N-SH细胞的增殖、迁移、侵袭和凋亡

该研究旨在探讨ROR1-AS1对神经母细胞瘤细胞SK-N-SH增殖、迁移、侵袭和凋亡的影响及作用机制。收集67例神经母细胞瘤组织和瘤旁组织,实时荧光定量PCR(RT-qPCR)检测组织中ROR1-AS1和miR-758-3p的表达情况。转染ROR1-AS1小干扰RNA、miR-758-3p模拟物或共转染ROR1-AS1小干扰RNA与miR-758-3p抑制剂至SK-N-SH细胞,细胞计数试剂盒-8(CCK-8)法检测细胞增殖,Transwell检测细胞迁移和侵袭,流式细胞术检测细胞凋亡,蛋白质印迹法检测CyclinD1、p21、Bcl-2、Bax、MMP-2和MMP-9的蛋白表达情况。双荧光素酶报告基因实验验证ROR1-AS1和miR-758-3p的调控关系。结果显示,神经母细胞瘤组织中ROR1-AS1的表达明显高于瘤旁组织,而miR-758-3p表达明显低于瘤旁组织。抑制ROR1-AS1表达或过表达miR-758-3p降低了SK-N-SH细胞活性、迁移数和侵袭数及CyclinD1、Bcl-2、MMP-2和MMP-9蛋白表达水平,而提高了细胞凋亡率及p21和Bax蛋白表达水平。ROR1-AS1在SK-N-SH细胞中靶向负调控miR-758-3p表达,干扰miR-758-3p可逆转抑制ROR1-AS1对SK-N-SH细胞增殖、迁移、侵袭和凋亡的影响。这提示抑制ROR1-AS1表达可能通过靶向上调miR-758-3p阻碍SK-N-SH细胞增殖、迁移和侵袭,并促进细胞凋亡,ROR1-AS1有可能成为神经母细胞瘤治疗的分子靶点。     

维甲酸对SK-N-SH细胞增殖和相关基因表达的影响

目的:研究维甲酸对SK-N-SH细胞的增殖和相关基因表达的影响.方法:通过苔盼蓝排除法绘制细胞生长曲线、流式细胞技术测定细胞周期、HE染色光镜观察细胞形态改变以及SABC免疫细胞化学梁色法观察维甲酸对SK-N-SH相关癌基因、抑癌基因表达的影响.结果:1μmol/LRA处理后,SK-N-SH细胞的增殖活动受到明显的抑制,处理第7天抑制率达36.16%;周期测定显示处理后出现明显的G0/G1期阻滞,由对照组的49.7%增加至62.7%,增加了26.2%;免疫细胞化学染色结果显示,处理后细胞癌基因c-myc、c-fos的表达较对照组明显降低,而抑癌基因p53、p27的表达则有所加强.结论:维甲酸能有效抑制SK-N-SH细胞的增殖活动,其对细胞的增殖抑制作用与RA下调c-myc、c-fos等癌基因以及上调p53、p27等抑癌基因的表达有关.     

Epstein-Barr virus lytic infection induces retinoic acid-responsive genes through induction of a retinol-metabolizing enzyme, DHRS9

Lytic Epstein-Barr virus (EBV) replication occurs in differentiated, but not undifferentiated, epithelial cells. Retinoic acid (RA) induces epithelial cell differentiation. The conversion of retinol into its active form, retinoic acid, requires retinol dehydrogenase enzymes. Here we show that AGS gastric carcinoma cells containing the lytic form of EBV infection have enhanced expression of a gene (DHRS9) encoding an enzyme that mediates conversion of retinol into RA. DHRS9 expression is also increased following induction of lytic viral infection in EBV-positive Burkitt lymphoma cells. We demonstrate that the EBV immediate-early protein, BZLF1, activates the DHRS9 promoter through a direct DNA binding mechanism. Furthermore, BZLF1 expression in AGS cells is sufficient to activate DHRS9 gene expression and increases the ability of retinol to induce the RA-responsive gene, CYP26A1. Production of RA during the lytic form of EBV infection may enhance viral replication by promoting keratinocyte differentiation.     

STAMBPL1 promotes the progression of lung adenocarcinoma by inhibiting DHRS2 expression

BackgroundLung cancer is responsible for the majority of cancer deaths in the world. We found a significant increase of STAMBPL1 expression in lung adenocarcinoma (LUAD) tissues and cells. However, its mechanism has not been clarified.MethodsLUAD tissues and adjacent normal tissues were collected from 62 patients treated in the First Affiliated Hospital of Wenzhou Medical University from August 2018 to August 2021. In vivo, the clinical data and STAMBPL1 expression of 62 patients with LUAD were analyzed by qPCR. In vitro, cell experiments were carried out after STAMBPL1 knockdown in A549 and H1299 cells to determine cell growth, migration rate, evasiveness, colony-forming ability, and apoptosis. Gene sequencing was used to explore the expression of various genes in A549 and H1299 cells to verify that DHRS2 was up-regulated after STAMBPL1 knockdown; cell experiments further detected the role of the DHRS2 gene after DHRS2 overexpression in A549 and H1299 cells. A rescue experiment was conducted to certify that STAMBPL1 promotes NSCLC progression by regulating DHRS2 expression.ResultsAfter STAMBPL1 knockdown by siRNA. Migration, invasion, colony formation, and proliferation of siRNA groups were suppressed than those of NC groups in A549 and H1299 cells, while the cell apoptosis rate of siRNA groups increased significantly. By using gene-sequence analysis, we found that the expression level of the DHRS2 gene was up-regulated in STAMBPL1 siRNA groups, compared with STAMBPL1 NC (negative control) groups in A549 and H1299, which was verified by qPCR and WB. Further experiments showed that the DHRS2 OE group was suppressed in cell proliferation, migration, and invasion in the A549 and H1299 cell lines compared to the DHRS2 NC group, while DHRS2 OE group was significantly enhanced in the cell apoptosis in the A549 and H1299 cell lines. According to the rescue experiment, cell proliferation, migration, and invasion of the STAMBPL1 SI+DHRS2 SI group were enhanced compared with the STAMBPL1 SI+DHRS2 NC group in A549 and H1299 cells, while the STAMBPL1 SI+DHRS2 OE group were further decreased.ConclusionsThe expression of STAMBPL1 mRNA is significantly up-regulated in LUAD, promoting the progression of LUAD by down-regulating the expression of DHRS2 and acting as a potential biomarker of LUAD.     

A comparative proteomic analysis for capsaicin-induced apoptosis between human hepatocarcinoma (HepG2) and human neuroblastoma (SK-N-SH) cells

The endogenous ROS levels were increased during HepG2 apoptosis, whereas they were decreased during SK-N-SH apoptosis in response to capsaicin treatments. We used 2-DE-based proteomics to analyze the altered protein levels in both cells, with special attention on oxidative stress proteins before and after capsaicin treatments. The 2-DE analysis demonstrated that 23 proteins were increased and 26 proteins were decreased significantly (fold change>1.4) in capsaicin-treated apoptotic HepG2 and SK-N-SH cells, respectively. The distinct effect of capsaicin-induced apoptosis on the expression pattern of HepG2 proteins includes the downregulation of some antioxidant enzymes including aldose reductase (AR), catalase, enolase 1, peroxiredoxin 1, but upregulation of peroxiredoxin 6, cytochrome c oxidase, and SOD2. In contrast, most antioxidant enzymes were increased in SK-N-SH cells in response to capsaicin, where catalase might play a pivotal role in maintenance of low ROS levels in the course of apoptosis. The global gene expression for oxidative stress and antioxidant defense genes revealed that 84 gene expressions were not significantly different in HepG2 cells between control and capsaicin-treated cells. In contrast, a number of oxidative genes were downregulated in SK-N-SH cells, supporting the evidence of low ROS environment in apoptotic SK-N-SH cells after capsaicin treatment. It was concluded that the different relationship between endogenous ROS levels and apoptosis of two cancer cells presumably resulted from complicated expression patterns of many oxidative stress and antioxidant genes, rather than the individual role of some classical antioxidant enzymes such as SOD and catalase.     

维甲酸对人神经母细胞瘤SK—N—SH细胞形态结构和分化标志物表达的影响

目的：观察维甲酸对人神经母细胞瘤SK-N-SH细胞形态与超微结构及其相关标志物表达的影响,以鉴定其对神经母细胞瘤细胞终末分化的诱导作用。方法：1μmol／L维甲酸处理SK—N—SH细胞,光镜、电镜和免疫细胞化学检测研究SK—N—SH细胞处理前后细胞形态、超微结构变化和神经元相关标志物的表达变化。结果：光镜与电镜观察结果显示,SK—N—SH细胞经1μmol／LRA处理后,细胞形态和超微结构产生了细胞呈极性状、伸出多个轴突树突状突起、细胞逐渐变小变圆并融合在一起形成类似神经节样结构、细胞表面微绒毛减少、核仁变少变小、常染色质增多、细胞器丰富发达等显著变化;免疫细胞化学检测显示经RA处理后SK-N-SH细胞NSE、MAP2、Synaptophysin的表达较对照组细胞明显加强。结论：维甲酸能改变SK—N—SH细胞形态和超微结构恶性表型特征,并促进与神经细胞相关的终末分化指标的表达,从而对人神经母细胞瘤细胞的终末分化具有显著的诱导作用。     

Molecular and functional evolution of human DHRS2 and DHRS4 duplicated genes

Human DHRS2 and DHRS4 genes code for similar NADP-dependent short-chain carbonyl-reductase enzymes having different substrate specificity. Human DHRS2 and DHRS4 enzymes share several common sequence motives including residues responsible for coenzyme binding as well as for the intimate catalytic oxido-reductase mechanism, while their substrate-binding sequences have very low similarity. We found that DHRS2 and DHRS4 genes are syntenic outparalogues originated from a duplication of the DHRS4 gene that took place before the formation of the mammalian clade. DHRS2 gene evolved more rapidly and underwent positive selection on more sites than the DHRS4 gene. DHRS2 sites under positive selection were mainly located on the enzyme active site thus showing that substrate specificity drove the divergence from the DHRS4 enzyme. Rapid divergent evolution brought the human DHRS2 enzyme to have subcellular localization, synthesis regulation and specialized cellular functions very different from those of the human DHRS4 enzyme.     

Antibody Fragments Directed against Different Portions of the Human Neural Cell Adhesion Molecule L1 Act as Inhibitors or Activators of L1 Function

The neural cell adhesion molecule L1 plays important roles in neuronal migration and survival, neuritogenesis and synaptogenesis. L1 has also been found in tumors of different origins, with levels of L1 expression correlating positively with the metastatic potential of tumors. To select antibodies targeting the varied functions of L1, we screened the Tomlinson library of recombinant human antibody fragments to identify antibodies binding to recombinant human L1 protein comprising the entire extracellular domain of human L1. We obtained four L1 binding single-chain variable fragment antibodies (scFvs), named I4, I6, I13, and I27 and showed by enzyme-linked immunosorbent assay (ELISA) that scFvs I4 and I6 have high affinity to the immunoglobulin-like (Ig) domains 1–4 of L1, while scFvs I13 and I27 bind strongly to the fibronectin type III homologous (Fn) domains 1–3 of L1. Application of scFvs I4 and I6 to human SK-N-SH neuroblastoma cells reduced proliferation and transmigration of these cells. Treatment of SK-N-SH cells with scFvs I13 and I27 enhanced cell proliferation and migration, neurite outgrowth, and protected against the toxic effects of H₂O₂ by increasing the ratio of Bcl-2/Bax. In addition, scFvs I4 and I6 inhibited and scFvs I13 and I27 promoted phosphorylation of src and Erk. Our findings indicate that scFvs reacting with the immunoglobulin-like domains 1–4 inhibit L1 functions, whereas scFvs interacting with the fibronectin type III domains 1–3 trigger L1 functions of cultured neuroblastoma cells.