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51.
以中油四号油桃(Prunus persica var. nectarina)为研究对象, 利用MEGA 6.0、MEME、GSDS和DNAMAN 6.0等软件对桃ERF家族数据进行生物信息学分析, 鉴定得到102个ERF转录因子家族基因, 并通过构建系统进化树将这102个基因分为10个子家族(I-X)。基因结构分析表明, 有81个基因不含内含子, 20个基因含有1个内含子, 有1个基因与其它成员差异较大, 含有5个内含子。保守元件分析表明, ERF家族包含20个保守元件, 其中Motif 1、Motif 2和Motif 4都属于AP2/ERF结构域, 同一个保守元件主要出现在同一个子家族中, 并且大部分保守元件的功能未知。VIII子家族基因的荧光定量PCR分析表明, 在桃叶芽处于不同的发育状态时, PpeERF068的表达量存在较大差异, 光照培养箱中培养的桃芽在萌发过程中各时期表达量变化趋势进一步表明该基因可能与叶芽萌发有关, 将其命名为PpeEBB1。该研究为进一步揭示PpeEBB1的分子机制奠定了基础, 并为桃树的栽培管理和熟期调控了提供理论指导。 相似文献
52.
Jun Sun Wei Wu Xiaofeng Tang Feifei Zhang Cheng Ju Renfeng Liu Yiping Liang Bo Yu Bin Lv Yuhong Guo Duo Zeng Xuchang Tao Min Wang Zhiping Zhang Changhua Zhang Xiao-Bin Lv 《Bioscience reports》2021,41(4)
Background: WT161, as a selective HDAC6 inhibitor, has been shown to play anti-tumor effects on several kinds of cancers. The aim of the present study is to explore the roles of WT161 in osteosarcoma and its underlying mechanisms.Methods: The anti-proliferative effect of WT161 on osteosarcoma cells was examined using MTT assay and colony formation assay. Cell apoptosis was analyzed using flow cytometer. The synergistic effect was evaluated by isobologram analysis using CompuSyn software. The osteosarcoma xenograft models were established to evaluate the anti-proliferative effect of WT161 in vivo.Results: WT161 suppressed the cell growth and induced apoptosis of osteosarcoma cells in a dose- and time-dependent manner. Mechanistically, we found that WT161 treatment obviously increased the protein level of PTEN and decreased the phosphorylation level of protein kinase-B (AKT). More importantly, WT161 showed synergistic inhibition with 5-FU on osteosarcoma cells in vitro and in vivo.Conclusions: These results indicate that WT161 inhibits the growth of osteosarcoma through PTEN and has a synergistic efficiency with 5-FU. 相似文献
53.
Hengdao Liu Hong Xiang Shaoli Zhao Haiqiang Sang Fenghua Lv Ruifang Chen Zhihao Shu Alex F. Chen Shuhua Chen Hongwei Lu 《Journal of cellular and molecular medicine》2019,23(2):798-810
The dipeptidyl peptidase 4 inhibitor vildagliptin (VLD), a widely used anti‐diabetic drug, exerts favourable effects on vascular endothelium in diabetes. We determined for the first time the improving effects of VLD on mitochondrial dysfunction in diabetic mice and human umbilical vein endothelial cells (HUVECs) cultured under hyperglycaemic conditions, and further explored the mechanism behind the anti‐diabetic activity. Mitochondrial ROS (mtROS) production was detected by fluorescent microscope and flow cytometry. Mitochondrial DNA damage and ATP synthesis were analysed by real time PCR and ATPlite assay, respectively. Mitochondrial network stained with MitoTracker Red to identify mitochondrial fragmentation was visualized under confocal microscopy. The expression levels of dynamin‐related proteins (Drp1 and Fis1) were determined by immunoblotting. We found that VLD significantly reduced mtROS production and mitochondrial DNA damage, but enhanced ATP synthesis in endothelium under diabetic conditions. Moreover, VLD reduced the expression of Drp1 and Fis1, blocked Drp1 translocation into mitochondria, and blunted mitochondrial fragmentation induced by hyperglycaemia. As a result, mitochondrial dysfunction was alleviated and mitochondrial morphology was restored by VLD. Additionally, VLD promoted the phosphorylation of AMPK and its target acetyl‐CoA carboxylase in the setting of high glucose, and AMPK activation led to a decreased expression and activation of Drp1. In conclusion, VLD improves endothelial mitochondrial dysfunction in diabetes, possibly through inhibiting Drp1‐mediated mitochondrial fission in an AMPK‐dependent manner. 相似文献
54.
Fangjiao Lv Yang Xu Dean W. Gabriel Xue Wang Ning Zhang Wenxing Liang 《Molecular & cellular proteomics : MCP》2022,21(5):100231
Fusarium oxysporum is one of the most abundant and diverse fungal species found in soils and includes nonpathogenic, endophytic, and pathogenic strains affecting a broad range of plant and animal hosts. Conidiation is the major mode of reproduction in many filamentous fungi, but the regulation of this process is largely unknown. Lysine acetylation (Kac) is an evolutionarily conserved and widespread posttranslational modification implicated in regulation of multiple metabolic processes. A total of 62 upregulated and 49 downregulated Kac proteins were identified in sporulating mycelia versus nonsporulating mycelia of F. oxysporum. Diverse cellular proteins, including glycolytic enzymes, ribosomal proteins, and endoplasmic reticulum–resident molecular chaperones, were differentially acetylated in the sporulation process. Altered Kac levels of three endoplasmic reticulum–resident molecular chaperones, PDIK70, HSP70K604, and HSP40K32 were identified that with important roles in F. oxysporum conidiation. Specifically, K70 acetylation (K70ac) was found to be crucial for maintaining stability and activity of protein disulphide isomerase and the K604ac of HSP70 and K32ac of HSP40 suppressed the detoxification ability of these heat shock proteins, resulting in higher levels of protein aggregation. During conidial formation, an increased level of PDIK70ac and decreased levels of HSP70K604ac and HSP40K32ac contributed to the proper processing of unfolded proteins and eliminated protein aggregation, which is beneficial for dramatic cell biological remodeling during conidiation in F. oxysporum. 相似文献
55.
Feng Xiei ;Wei Liu ;Fen Feng ;Xin Li ;Li Yang ;Deguan Lv ;Xuping Qin ;Lanfang Li ;Linxi Chen 《Acta biochimica et biophysica Sinica》2014,(8):699-708
This study is designed to investigate whether APJ receptor acts as a sensor in static pressure-induced cardiomyocyte hypertrophy and to investigate the mechanism of PI3K- autophagy pathway. The left ventricular hypertrophy rat model was established by coarctation of abdominal aorta. H9c2 rat cardiomyocytes were cultured in the presence of static pressure which was given by a custom-made pressure in- cubator. The results revealed that the expression of apelin/ APJ system, PI3K, Akt and their phosphorylation were sig- nificantly increased in the operation group. Static pressure up-regulated the APJ expression, PI3K phosphorylation, Akt phosphorylation, LC3-Ⅱ/Ⅰ and beclin-1 expression in cardio- myocytes. APJ shRNA pGPU6/Neo-rat-399, PI3K inhibitor LY294002, Akt inhibitor 1701-1 blocked the up-regulation of APJ, PI3K phosphorylation, Akt phosphorylation, LC3-H/I and beclin-1 expression, respectively. Moreover, static pres- sure increased the diameter, volume, protein content of cells, and these could be reversed when the cells were treated with pGPU6/Neo-rat-399, LY294002, and autop- hagy inhibitor 3-methyladenine, respectively. These results suggested that static pressure up-regulates APJ expression to promote cardiomyocyte hypertrophy by a PI3K-autop- hagy pathway. 相似文献
56.
57.
Lin‐Li Lv Ye Feng Tao‐Tao Tang Bi‐Cheng Liu 《Journal of cellular and molecular medicine》2019,23(2):731-739
Extracellular vesicles (EVs) are released to maintain cellular homeostasis as well as to mediate cell communication by spreading protective or injury signals to neighbour or remote cells. In kidney, increasing evidence support that EVs are signalling vesicles for different segments of tubules, intra‐glomerular, glomerular‐tubule and tubule‐interstitial communication. EVs released by kidney resident and infiltrating cells can be isolated from urine and were found to be promising biomarkers for kidney disease, reflecting deterioration of renal function and histological change. We have here summarized the recent progress about the functional role of EVs in kidney disease as well as challenges and future directions involved. 相似文献
58.
It has been known that Rho-associated protein kinase (ROCK) signaling regulates the migration of vascular smooth muscle cells (VSMCs). However, the isoform-specific roles of ROCK and its underlying mechanism in VSMC migration are not well understood. The current study thus aimed to investigate the roles of ROCK1/2 and their relationship to the MAPK signaling pathway in platelet-derived growth factor (PDGF)-induced rat aorta VSMC migration by manipulating ROCK gene expression. The results revealed that ROCK1 small interfering ribonucleic acid (siRNA) rather than ROCK2 siRNA decreased PDGF-BB-generated VSMC migration, and upregulation of ROCK1 expression via transfection of constructed pEGFP-C1/ROCK1 plasmid further increased the migration of PDGF-BB-treated VSMCs. In PDGF-treated VSMCs, ROCK1 siRNA did not affect the phosphorylation levels of ERK and p38 in the cytoplasm, but decreased the level of ERK phosphorylation in the nucleus. These findings demonstrate that activated ROCK1 can promote VSMC migration through facilitating phosphorylation and nuclear translocation of ERK protein. 相似文献
59.
The aim of the present study is to investigate the expression of a novel estrogen receptor, G protein-coupled receptor 30 (GPR30) and its correlation with matrix metalloproteinases-9 (MMP-9) in epithelial ovarian cancer (EOC). Ovary tissues were obtained from 39 female patients, including 30 cases of EOC and 9 cases of benign ovarian tumor. Four normal ovary tissues were used as control. Immunohistochemical staining was used to detect the expressions of GPR30 and MMP-9. Chi square test, Fisher's exact test and Spearman's rank correlation analysis were used for statistical analysis. The results showed that GPR30 overexpression rate in EOC cases was significantly higher than those in benign ovarian tumor and normal ovary cases. Whereas MMP-9 overexpression rate in EOC cases was significantly higher than that in normal ovary cases, without any difference to that in benign ovarian tumor cases. To demonstrate the relationship between GPR30 and clinicopathological variables of EOC, we further analyzed the pathology type, FIGO stage and age of patients sampled in our study. The analysis showed there were significant differences of GPR30 overexpression rate among various pathology types and different FIGO stages (P<0.05), and no significant difference of both GPR30 and MMP-9 among three age groups (P>0.05). Moreover, GPR30 expression was positively correlated with MMP-9 (r(s)=1.000, P=0.002). These results suggest that GPR30 may be involved in the invasion and metastasis of EOC, being a potential index of EOC early diagnosis and malignancy grade prediction. 相似文献
60.
Differential role of microenvironment in microencapsulation for improved cell tolerance to stress 总被引:6,自引:0,他引:6
Sun ZJ Lv GJ Li SY Yu WT Wang W Xie YB Ma X 《Applied microbiology and biotechnology》2007,75(6):1419-1427
The effect of the microenvironment in alginate–chitosan–alginate (ACA) microcapsules with liquid core (LCM) and solid core
(SCM) on the physiology and stress tolerance of Sacchromyces cerevisiae was studied. The suspended cells were used as control. Cells cultured in liquid core microcapsules showed a nearly twofold
increase in the intracellular glycerol content, trehalose content, and the superoxide dismutase (SOD) activity, which are
stress tolerance substances, while SCM did not cause the significant physiological variation. In accordance with the physiological
modification after being challenged with osmotic stress (NaCl), oxidative stress (H2O2), ethanol stress, and heat shock stress, the cell survival in LCM was increased. However, SCM can only protect the cells
from damaging under ethanol stress. Cells released from LCM were more resistant to hyperosmotic stress, oxidative stress,
and heat shock stress than cells liberated from SCM. Based on reasonable analysis, a method was established to estimate the
effect of microenvironment of LCM and SCM on the protection of cells against stress factors. It was found that the resistance
of LCM to hyperosmotic stress, oxidative stress, and heat shock stress mainly depend on the domestication effect of LCM’s
microenvironment. The physical barrier of LCM constituted by alginate–chitosan membrane and liquid alginate matrix separated
the cells from the damage of oxidative stress and ethanol stress. The significant tolerance against ethanol stress of SCM
attributed to the physical barrier consists of solid alginate–calcium matrix and alginate–chitosan membrane. 相似文献