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61.
Du  Xuemei  Fang  Ting  Liu  Yan  Huang  Liying  Wang  Xiaoli  Zhang  Jie  Cui  Yangbo  Zang  Maosen  Wang  Guoying  Fu  Junjie  Liu  Yunjun 《In vitro cellular & developmental biology. Plant》2020,56(2):159-168
In Vitro Cellular & Developmental Biology - Plant - Callus induction in plants is similar to pluripotent stem cell induction in animals and can incite global changes in gene expression....  相似文献   
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DNA‐binding protein A (dbpA) is reported to be upregulated in many cancers and associated with tumor progress. The present study aimed to investigate the role of dbpA in 5‐fluorouracil (5‐FU)‐resistant and oxaliplatin (L‐OHP)‐resistant colorectal cancer (CRC) cells. We found that 5‐FU and L‐OPH treatment promoted the expression of dbpA. Enhanced dbpA promoted the drug resistance of SW620 cells to 5‐FU and L‐OHP. DbpA knockdown inhibited cell proliferation, induced cell apoptosis, and cell cycle arrested in SW620/5‐FU and SW620/L‐OHP cells. Besides, dbpA short hairpin RNA (shRNA) enhanced the cytotoxicity of 5‐FU and L‐OHP to SW620/5‐FU and SW620/L‐OHP cells. Meanwhile, dbpA shRNA inhibited the activation of the Wnt/β‐catenin pathway that induced by 5‐FU stimulation in SW620/5‐FU cells. Activation of the Wnt/β‐catenin pathway or overexpression of checkpoint kinase 1 (Chk1) abrogated the promoting effect of dbpA downregulation on 5‐FU sensitivity of CRC cells. Importantly, downregulation of dbpA suppressed tumor growth and promoted CRC cells sensitivity to 5‐FU in vivo. Our study indicated that the knockdown of dbpA enhanced the sensitivity of CRC cells to 5‐FU via Wnt/β‐catenin/Chk1 pathway, and DbpA may be a potential therapeutic target to sensitize drug resistance CRC to 5‐FU and L‐OHP.  相似文献   
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Reticulon and REEP family of proteins stabilize the high curvature of endoplasmic reticulum (ER) tubules. Plasmodium berghei Yop1 (PbYop1) is a REEP5 homolog in Plasmodium. Here, we characterize its function using a gene-knockout (Pbyop1∆). Pbyop1∆ asexual stage parasites display abnormal ER architecture and an enlarged digestive vacuole. The erythrocytic cycle of Pbyop1∆ parasites is severely attenuated and the incidence of experimental cerebral malaria is significantly decreased in Pbyop1∆-infected mice. Pbyop1∆ sporozoites have reduced speed, are slower to invade host cells but give rise to equal numbers of infected HepG2 cells, as WT sporozoites. We propose that PbYOP1’s disruption may lead to defects in trafficking and secretion of a subset of proteins required for parasite development and invasion of erythrocytes. Furthermore, the maintenance of ER morphology in different parasite stages is likely to depend on different proteins.  相似文献   
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Chimonanthus salicifolius, a member of the Calycanthaceae of magnoliids, is one of the most famous medicinal plants in Eastern China. Here, we report a chromosome‐level genome assembly of Csalicifolius, comprising 820.1 Mb of genomic sequence with a contig N50 of 2.3 Mb and containing 36 651 annotated protein‐coding genes. Phylogenetic analyses revealed that magnoliids were sister to the eudicots. Two rounds of ancient whole‐genome duplication were inferred in the Csalicifolious genome. One is shared by Calycanthaceae after its divergence with Lauraceae, and the other is in the ancestry of Magnoliales and Laurales. Notably, long genes with > 20 kb in length were much more prevalent in the magnoliid genomes compared with other angiosperms, which could be caused by the length expansion of introns inserted by transposon elements. Homologous genes within the flavonoid pathway for Csalicifolius were identified, and correlation of the gene expression and the contents of flavonoid metabolites revealed potential critical genes involved in flavonoids biosynthesis. This study not only provides an additional whole‐genome sequence from the magnoliids, but also opens the door to functional genomic research and molecular breeding of Csalicifolius.  相似文献   
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ABC转运蛋白及其在合成生物学中的应用   总被引:1,自引:0,他引:1  
ABC转运蛋白(ATP-binding cassette transporter,ABC transporter)作为一种超大膜转运蛋白家族,在大多数生物体中发挥着重要作用。文中从结构特征、转运机制以及生理功能等方面论述了ABC转运蛋白的研究进展,进而着重综述了近些年来ABC转运蛋白在合成生物学领域中的应用,并为今后进一步的研究提出了展望,希望为扩展其应用提供指导。  相似文献   
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Foraging animals must balance benefits of food acquisition with costs induced by a post-prandial reduction in performance. Eating to satiation can lead to a reduction in locomotor and escape performance, which increases risk should a threat subsequently arises, but limiting feeding behaviour may be maladaptive if food intake is unnecessarily reduced in the prediction of threats that do not arise. The efficacy of the trade-off between continued and interrupted feeding therefore relies on information about the future risk, which is imperfect. Here, we find that black carp (Mylopharyngodon piceus) can balance this trade-off using an a posteriori strategy; by eating to satiation but regurgitating already ingested food when a threat arises. While degrees of satiation (DS) equal to or greater than 60% reduce elements of escape performance (turning angle, angular velocity, distance moved, linear velocity), at 40% DS or lower, performance in these tasks approaches levels comparable to that at 0% satiation. After experiencing a chasing event, we find that fish are able to regurgitate already ingested food, thereby changing the amount of food in their gastrointestinal tract to consistent levels that maintain high escape performance. Remarkably, regurgitation results in degrees of satiation between 40 and 60% DS, regardless of whether they had previously fed to 40, 60 or 100% DS. Using this response, fish are able to maximize food intake, but regurgitate extra food to maintain escape performance when they encounter a threat. This novel strategy may be effective for continual grazers and species with imperfect information about the level of threat in their environment.  相似文献   
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Aidi injection (ADI), a traditional Chinese biomedical preparation, is a promising adjuvant therapy for gynecologic tumors (GTs), including cervical cancer (CC), endometrial cancer (EC), and ovarian cancer (OC). Although studies have reported positively on ADI therapy, its exact effects and safety in GT patients remain controversial. Therefore, a wide-ranging systematic search of electronic databases was performed for this meta-analysis. Data from 38 trials including 3309 GT patients were analyzed. The results indicated that the combination of conventional treatment and ADI markedly improved the patients’ overall response rate (P<0.00001), disease control rate (P<0.00001), and quality of life (P<0.05) compared with conventional treatment alone. Furthermore, patient immunity was enhanced with combined treatment, as indicated by significantly increased percentages of CD3+ (P=0.005) and CD4+ (P<0.00001) and increased CD4+/CD8+ ratio (P=0.001). Most of the adverse events caused by radiochemotherapy such as gastrointestinal issues, leukopenia, thrombocytopenia, and hepatotoxicity, (P<0.05 for all) were significantly alleviated when ADI was used in the GT patients. However, other adverse events such as nephrotoxicity, diarrhea, alopecia, and neurotoxicity did not significantly differ between the two groups. Overall, these results suggest that the combination of conventional and ADI treatment is more effective than conventional treatment alone.  相似文献   
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