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81.
Ying Wang Yunjing Zhang Xinwan Su Qiongzi Qiu Yuan Yuan Chunhua Weng Sailan Zou Yan Tian Weidong Han Pengyuan Liu Xingyi Guo Jianhua Mao Xianghui Fu Ping Wang Weiqiang Lin 《International journal of biological sciences》2022,18(4):1491
Clear cell renal cell carcinoma (ccRCC) is a primary kidney cancer with high aggressive phenotype and extremely poor prognosis. Accumulating evidence suggests that circular RNAs (circRNAs) play pivotal roles in the occurrence and development of various human cancers. However, the expression, clinical significance and regulatory role of circRNAs in ccRCC remain largely unclear. Here we report that circDVL1 to be reduced in the serums and tissues from ccRCC patients, and to negatively correlate with ccRCC malignant features. Overexpression of circDVL1 inhibits proliferation, induces G1/S arrest, triggers apoptosis, and reduces migration and invasion in different ccRCC cells in vitro. Correspondingly, circDVL1 overexpression suppresses ccRCC tumorigenicity in a mouse xenograft model. Mechanistically, circDVL1 serves as a sponge for oncogenic miR-412-3p, thereby preventing miR-412-3p-mediated repression of its target protocadherin 7 (PCDH7) in ccRCC cells. Collectively, our results demonstrate that circDVL1 exerts tumor-suppressive function during ccRCC progression through circDVL1/miR-412-3p/PCDH7 axis, and suggest that circDVL1 could be a novel diagnostic and prognositc marker and therapeutic target for ccRCC. 相似文献
82.
Lei Yang Lingqian Tian Leshan Li Qiuhong Liu Xiang Guo Yuan Zhou Rongjuan Pei Xinwen Chen Yun Wang 《中国病毒学》2022,37(3):341-347
Transformation-associated recombination (TAR) has been widely used to assemble large DNA constructs. One of the significant obstacles hindering assembly efficiency is the presence of error-prone DNA repair pathways in yeast, which results in vector backbone recircularization or illegitimate recombination products. To increase TAR assembly efficiency, we prepared a dual-selective TAR vector, pGFCS, by adding a PADH1-URA3 cassette to a previously described yeast-bacteria shuttle vector, pGF, harboring a PHIS3-HIS3 cassette as a positive selection marker. This new cassette works as a negative selection marker to ensure that yeast harboring a recircularized vector cannot propagate in the presence of 5-fluoroorotic acid. To prevent pGFCS bearing ura3 from recombining with endogenous ura3-52 in the yeast genome, a highly transformable Saccharomyces cerevisiae strain, VL6-48B, was prepared by chromosomal substitution of ura3-52 with a transgene conferring resistance to blasticidin. A 55-kb genomic fragment of monkeypox virus encompassing primary detection targets for quantitative PCR was assembled by TAR using pGFCS in VL6-48B. The pGFCS-mediated TAR assembly showed a zero rate of vector recircularization and an average correct assembly yield of 79% indicating that the dual-selection strategy provides an efficient approach to optimizing TAR assembly. 相似文献
83.
Hang Yang Huijun Yuan Xiaohui Zhao Meng Xun Shangrui Guo Nan Wang Bing Liu Hongliang Wang 《中国病毒学》2022,37(3):380-389
The recent COVID-19 pandemic poses a global health emergency. Cellular entry of the causative agent SARS-CoV-2 is mediated by its spike protein interacting with cellular receptor-human angiotensin converting enzyme 2 (ACE2). Here, by using lentivirus based pseudotypes bearing spike protein, we demonstrated that entry of SARS-CoV-2 into host cells was dependent on clathrin-mediated endocytosis, and phosphoinositides played essential roles during this process. In addition, we showed that the intracellular domain and the catalytic activity of ACE2 were not required for efficient virus entry. Finally, we showed that the current predominant Delta variant, although with high infectivity and high syncytium formation, also entered cells through clathrin-mediated endocytosis. These results provide new insights into SARS-CoV-2 cellular entry and present proof of principle that targeting viral entry could be an effective way to treat different variant infections. 相似文献
84.
Dan Chen Satoko Ito Hong Yuan Toshinori Hyodo Kenji Kadomatsu Michinari Hamaguchi Takeshi Senga 《Cell cycle (Georgetown, Tex.)》2015,14(10):1529-1539
Echinoderm microtubule-associated protein (EMAP)-like (EML) family proteins are microtubule-associated proteins that have a conserved hydrophobic EMAP-like protein (HELP) domain and multiple WD40 domains. In this study, we examined the role of EML4, which is a member of the EML family, in cell division. Time-lapse microscopy analysis demonstrated that EML4 depletion induced chromosome misalignment during metaphase and delayed anaphase initiation. Further analysis by immunofluorescence showed that EML4 was required for the organization of the mitotic spindle and for the proper attachment of kinetochores to microtubules. We searched for EML4-associating proteins by mass spectrometry analysis and found that the nuclear distribution gene C (NUDC) protein, which is a critical factor for the progression of mitosis, was associated with EML4. This interaction was mediated by the WD40 repeat of EML4 and by the C-terminus of NUDC. In the absence of EML4, NUDC was no longer able to localize to the mitotic spindle, whereas NUDC was dispensable for EML4 localization. Our results show that EML4 is critical for the loading of NUDC onto the mitotic spindle for mitotic progression. 相似文献
85.
Miao Liu Yanfei Ru Yihua Gu Jianan Tang Tiancheng Zhang Jun Wu Fudong Yu Yao Yuan Chen Xu Jian Wang Huijuan Shi 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(3):660-668
Background
We previously cloned the Ssp411 gene. We found that the Ssp411 protein is predominantly expressed in elongated spermatids in the rat testis in a stage-dependent manner. Although our findings strongly suggested that Ssp411 might play an important role in mammalian spermatogenesis, this hypothesis has not been studied.Methods
We first used real-time PCR, Western blotting and immunohistochemistry to confirm that the expression pattern of Ssp411 in several murine tissues is similar to its expression pattern in corresponding rat tissues. To better understand the roles of Ssp411 in male reproduction in vivo, we identified and characterized an Ssp411 expression-disrupted murine strain (Ssp411PB/PB) that was generated by piggyBac (PB) transposon insertion. We studied Ssp411-interacting proteins using proteome microarray, co-IP and GST pull-down assay.Results
Both Ssp411 mRNA and protein were detected exclusively in spermatids after step 9 during spermiogenesis in testis. Phenotypic analysis suggested that only Ssp411PB/PB males are sterile. These males have smaller testes, reduced sperm counts, decreased sperm motility and deformed spermatozoa. Microscopy analysis indicated that the manchette, a structurally reshaped sperm head, is aberrant in Ssp411PB/PB spermatids. The results of proteome microarray analysis and GST pull-down assays suggested that Ssp411 participates the ubiquitin-proteasome system by interacting with PSMC3. This has been reported to be manchette-associated and important for the head shaping of spermatids.Conclusions
Our study suggested that Ssp411 is required for spermiogenesis. It seems to play a role in sperm head shaping. The lack of Ssp411 causes sperm deformation and results in male infertility.General significance
Ssp411PB/PB mouse strain is an animal model of idiopathic oligoasthenoteratozoospermia (iOAT), and the gene may represent a therapeutic target for iOAT patients. 相似文献86.
Yuan Xu Chen Shao Xinpeng Fan Alan Warren Khaled A. S. Al-Rasheid Weibo Song Norbert Wilbert 《Polar Biology》2016,39(8):1439-1453
Antarctica is a remote and isolated biotope which makes it an ideal location for studying new and endemic species. Since there is little literature available on the diversity of ciliates in this area, a taxonomic survey of ciliates from melt-water of Collins glacier, King George Island, was carried out from January to March 2006. As a result, the morphology and infraciliature of five ciliates, including one new species, are described using live observations and silver staining: Gastronauta multistriata nov. spec., Neokeronopsis asiatica Foissner et al., 2010, Paraholosticha muscicola Kahl, 1932, Oxytricha sp., and Cyclidium glaucoma Müller, 1786. Gastronauta multistriata nov. spec. is distinguished from its congeners by the following combination of characters: cell size in vivo on average 80 × 40 μm; 5–9 kineties in left ciliary field; 18–23 kineties in right ciliary field, including 10–12 postoral kineties; 7–10 preoral kineties; dorsal brush along anterior dorsal margin, consisting of 5–8 groups of basal bodies. The only minor differences between the current population of N. asiatica and a previously described Antarctic population are the numbers of caudal cirri (6–10 vs. 8–15) and dorsal kineties (11–13 vs. 12–18). Paraholosticha sterkii is synonymised with P. muscicola. The Antarctic population of C. glaucoma corresponds well with a former population from China, the only difference being the number of kinetids in SK n (11–17 vs. 9–11). This work will contribute to the understanding of ciliate diversity in this little studied area. 相似文献
87.
Construction of a high density integrated genetic map for cucumber (Cucumis sativus L.) 总被引:1,自引:0,他引:1
Zhang WW Pan JS He HL Zhang C Li Z Zhao JL Yuan XJ Zhu LH Huang SW Cai R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(2):249-259
The high-density consensus map was constructed based on the GY14 × PI 183967 map from an inter-subspecific cross and the extended
S94 × S06 map from an intra-subspecific cross. The consensus map was composed of 1,369 loci, including 1,152 SSR loci, 192
SRAP loci, 21 SCAR loci and one STS locus as well as three gene loci of fruit external quality traits in seven chromosomes,
and spanned 700.5 cM, of which 682.7 cM (97.5%) were covered by SSR markers. The average genetic distance and physical interval
between loci were 0.51 cM and ~268 kbp, respectively. Additionally, the physical position of the sequence-associated markers
aligned along the assembled cucumber genome sequence established a relationship between genetic maps and cucumber genome sequence
and to a great extent validated the order of markers in individual maps and consensus map. This consensus map with a high
marker density and well-ordered markers is a saturated and reliable linkage map for genetic analysis of cucumber or the Cucurbitaceae
family of plants. 相似文献
88.
ITMSQ: A software tool for N‐ and C‐terminal fragment ion pairs based isobaric tandem mass spectrometry quantification 下载免费PDF全文
Li‐Qi Xie Lei Zhang Ai‐Ying Nie Guo‐Quan Yan Jun Yao Yang Zhang Peng‐Yuan Yang Hao‐Jie Lu 《Proteomics》2015,15(22):3755-3764
Tandem MS (MS2) quantification using the series of N‐ and C‐terminal fragment ion pairs generated from isobaric‐labelled peptides was recently considered an accurate strategy in quantitative proteomics. However, the presence of multiplexed terminal fragment ion in MS2 spectra may reduce the efficiency of peptide identification, resulting in lower identification scores or even incorrect assignments. To address this issue, we developed a quantitative software tool, denoted isobaric tandem MS quantification (ITMSQ), to improve N‐ and C‐terminal fragment ion pairs based isobaric MS2 quantification. A spectrum splitting module was designed to separate the MS2 spectra from different samples, increasing the accuracy of both identification and quantification. ITMSQ offers a convenient interface through which parameters can be changed along with the labelling method, and the result files and all of the intermediate files can be exported. We performed an analysis of in vivo terminal amino acid labelling labelled HeLa samples and found that the numbers of quantified proteins and peptides increased by 13.64 and 27.52% after spectrum splitting, respectively. In conclusion, ITMSQ provides an accurate and reliable quantitative solutionfor N‐ and C‐terminal fragment ion pairs based isobaric MS2 quantitative methods. 相似文献
89.
Yuanyuan Yu Lei Hou Xu Shi Xiaoru Sun Xinhui Liu Yifan Yu Zhongshang Yuan Hongkai Li Fuzhong Xue 《PLoS genetics》2022,18(3)
Nonrandom selection in one-sample Mendelian Randomization (MR) results in biased estimates and inflated type I error rates only when the selection effects are sufficiently large. In two-sample MR, the different selection mechanisms in two samples may more seriously affect the causal effect estimation. Firstly, we propose sufficient conditions for causal effect invariance under different selection mechanisms using two-sample MR methods. In the simulation study, we consider 49 possible selection mechanisms in two-sample MR, which depend on genetic variants (G), exposures (X), outcomes (Y) and their combination. We further compare eight pleiotropy-robust methods under different selection mechanisms. Results of simulation reveal that nonrandom selection in sample II has a larger influence on biases and type I error rates than those in sample I. Furthermore, selections depending on X+Y, G+Y, or G+X+Y in sample II lead to larger biases than other selection mechanisms. Notably, when selection depends on Y, bias of causal estimation for non-zero causal effect is larger than that for null causal effect. Especially, the mode based estimate has the largest standard errors among the eight methods. In the absence of pleiotropy, selections depending on Y or G in sample II show nearly unbiased causal effect estimations when the casual effect is null. In the scenarios of balanced pleiotropy, all eight MR methods, especially MR-Egger, demonstrate large biases because the nonrandom selections result in the violation of the Instrument Strength Independent of Direct Effect (InSIDE) assumption. When directional pleiotropy exists, nonrandom selections have a severe impact on the eight MR methods. Application demonstrates that the nonrandom selection in sample II (coronary heart disease patients) can magnify the causal effect estimation of obesity on HbA1c levels. In conclusion, nonrandom selection in two-sample MR exacerbates the bias of causal effect estimation for pleiotropy-robust MR methods. 相似文献
90.