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Liu Yaling Geng Yaping Song Meiling Zhang Pengfei Hou Junling Wang Wenquan 《Plant Molecular Biology Reporter》2019,37(5-6):401-412
Plant Molecular Biology Reporter - Glycyrrhiza is a widely used traditional Chinese herb with medicinal value. Recently, however, Glycyrrhiza biodiversity has faced an unprecedented threat due to... 相似文献
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Pengfei Diao Yue Song Han Ge Yaping Wu Jin Li Wei Zhang Yanling Wang Jie Cheng 《Journal of cellular biochemistry》2019,120(6):10010-10020
Deregulated long noncoding RNAs (lncRNA) have been critically implicated in tumorigenesis and serve as novel diagnostic and prognostic biomarkers. Here we sought to develop a prognostic lncRNA signature in patients with head and neck squamous cell carcinoma (HNSCC). Original RNA-seq data of 499 HNSCC samples were retrieved from The Cancer Genome Atlas database, which was randomly divided into training and testing set. Univariate Cox regression survival analysis, robust likelihood-based survival model and random sampling iterations were applied to identify prognostic lncRNA candidates in the training cohort. A prognostic risk score was developed based on the Cox coefficient of four individual lncRNA imputed as follows: (0.14546 × expression level of RP11-366H4.1) + (0.27106 × expression level of LINC01123) + (0.54316 × expression level of RP11-110I1.14) + (−0.48794 × expression level of CTD-2506J14.1). Kaplan-Meier analysis revealed that patients with high-risk score had significantly reduced overall survival as compared with those with low-risk score when patients in training, testing, and validation cohorts were stratified into high- or low-risk subgroups. Multivariate survival analysis further revealed that this 4-lncRNA signature was a novel and important prognostic factor independent of multiple clinicopathological parameters. Importantly, ROC analyses indicated that predictive accuracy and sensitivity of this 4-lncRNA signature outperformed those previously well-established prognostic factors. Noticeably, prognostic score based on quantification of these 4-lncRNA via qRT-PCR in another independent HNSCC cohort robustly stratified patients into subgroups with high or low survival. Taken together, we developed a robust 4-lncRNA prognostic signature for HNSCC that might provide a novel powerful prognostic biomarker for precision oncology. 相似文献
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Lin Li Yaping Zhang Wanzhi Ma Hui Chen Mengqin Liu Ran An Bingxiao Cheng Xingguo Liang 《Nucleic acids research》2022,50(2):684
In vivo, left-handed DNA duplex (usually refers to Z-DNA) is mainly formed in the region of DNA with alternating purine pyrimidine (APP) sequence and plays significant biological roles. It is well known that d(CG)n sequence can form Z-DNA most easily under negative supercoil conditions, but its essence has not been well clarified. The study on sequence dependence of Z-DNA stability is very difficult without modification or inducers. Here, by the strong topological constraint caused by hybridization of two complementary short circular ssDNAs, left-handed duplex part was generated for various sequences, and their characteristics were investigated by using gel-shift after binding to specific proteins, CD and Tm analysis, and restriction enzyme cleavage. Under the strong topological constraint, non-APP sequences can also form left-handed DNA duplex as stable as that of APP sequences. As compared with non-APP sequences, the thermal stability difference for APP sequences between Z-form and B-form is smaller, which may be the reason that Z-DNA forms preferentially for APP ones. This result can help us to understand why nature selected APP sequences to regulate gene expression by transient Z-DNA formation, as well as why polymer with chirality can usually form both duplexes with left- or right-handed helix. 相似文献
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Yu Ruan Jiaqiao Hu Yaping Che Yanyan Liu Zhenhuan Luo Jin Cheng Qi Han He He Qinghua Zhou 《Cell death & disease》2022,13(2)
Mitochondrial dysfunction is becoming one of the main pathology factors involved in the etiology of neurological disorders. Recently, mutations of the coiled-coil-helix-coiled-coil-helix domain containing 2 (CHCHD2) and 10 (CHCHD10) which encode two homologous proteins that belong to the mitochondrial CHCH domain protein family, are linked to Parkinson’s disease and amyotrophic lateral sclerosis (ALS)/frontotemporal dementia (FTD), respectively. However, the physiological and pathological roles of these twin proteins have not been well elaborated. Here, we show that, in physiological conditions, CHCHD2 and CHCHD10 interact with OMA1 and suppress its enzyme activity, which not only restrains the initiation of the mitochondrial integrated response stress (mtISR), but also suppresses the processing of OPA1 for mitochondrial fusion. Further, during mitochondria stress-induced by carbonyl cyanide m-chlorophenylhydrazone (CCCP) treatment, CHCHD2 and CHCHD10 translocate to the cytosol and interacte with eIF2a, which attenuates mtISR overactivation by suppressing eIF2a phosphorylation and its downstream response. As such, knockdown of CHCHD2 and CHCHD10 triggers mitochondrial ISR, and such cellular response is enhanced by CCCP treatment. Therefore, our findings demonstrate the first “mtISR suppressor” localized in mitochondria for regulating stress responses in mammalian cells, which has a profound pathological impact on the CHCH2/CHCH10-linked neurodegenerative disorder.Subject terms: Stress signalling, Mitochondria 相似文献
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以琼脂粉为基质制备金属螯合载体,并用于固定重组腈水解酶。研究发现:制备金属螯合载体最合适的金属离子为Zn2+。当Zn2+离子浓度0.3 mol/L、给酶量15.6 mg/g、固定化pH 8.0、固定化温度40℃时,制得的固定化酶活性最高。固定化酶最适反应温度为50℃、最适反应pH为7.0。当扁桃腈浓度为10 mmol/L、反应1 h时,固定化酶最大产率为0.041 mmol/(g·h);在反应12 h时,产物e.e.值可达到99%以上。固定化酶重复使用8次以后,酶活力仍保持在45%。 相似文献
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黑叶猴和灰叶猴的线粒体DNA限制性片段长度多态研究 总被引:1,自引:0,他引:1
本文以15种限制性内切酶分析黑叶猴和灰叶猴种内及种间mtDNA多态。从各个样品中分别检出了41—50个酶切位点。综合15种限制内酶的酶切类型,在2只黑叶猴和2只灰叶猴中分别检出了两种限制性类型,并与其4个地理来源相对应。结合恒河猴和红面猴的资料,构建了4种猴科动物的分子系统树。结果表明,黑叶猴和灰叶猴种内的分歧分别始于30和35万年以前,两种叶猴的分离始于190万年以前,猴亚科和疣猴亚科的分离应早于1100万年。叶猴属在中国的扩散不是很晚才发生的。 相似文献
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