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Liangjie Niu Huiying Ding Ruiqi Hao Hui Liu Xiaolin Wu Xiuli Hu Wei Wang 《Plant, cell & environment》2019,42(12):3355-3371
Starch is the major form of carbohydrate storage in plants and exists as discrete starch granules (SGs). Isolation of high‐quality SGs in different plant tissues is a prerequisite for studying the roles of SGs during plant growth, development, and responses to abiotic stress. However, it is difficult to isolate transitory SGs from leaves and storage SGs from pollen grains due to their small sizes and low quantities. Herein, we develop a novel method for isolating SGs by using the aqueous two‐phase system (ATS) of ethanol/NaH2PO4. The ATS method efficiently separated SGs from contaminants based on their differences in density, solubility, and polarity. Using this method, we first isolated and purified three kinds of SGs from maize seeds, pollen, and leaves. The biochemical, microscopic, and proteomic analyses demonstrated the high purity of the isolated SGs. Proteomic analysis revealed distinct differences in SG‐bound proteins between seed SGs and pollen SGs. As a simple, rapid, and low‐cost method, the ATS‐based method exhibits highly universal and reproducible results for starch‐containing tissues in various plant species. 相似文献
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Ho-Yeon Oh Xun Jin Jong-Geun Kim Myung-Joo Oh Xumin Pian Jun-Mo Kim Moon-Seok Yoon Chae-Ik Son Young Sik Lee Ki-Chang Hong Hyunggee Kim Yun-Jaie Choi Kwang Youn Whang 《BMC cell biology》2007,8(1):1-8
Background
The pig, Sus scrofa domestica includes both the miniature and commercial domestic breed. These animals have influenced the human life and economies and have been studied throughout history. Although the miniature breeds are more recent and have increasingly been used in a variety of biomedical studies, their cell lines have rarely been established. Therefore, we sought to establish primary and immortal cell lines derived from both the miniature and domestic pig to better enable insight into possible in vivo growth differences.Results
The in vitro lifespan of primary domestic pig fibroblast (PF) and miniature pig fibroblast (MPF) cells using a standard 3T3 protocol was determined. Both of the primary PF and MPF cells were shown to have a two-step replicative senescence barrier. Primary MPF cells exhibited a relatively shorter lifespan and slower proliferation rate compared to those of primary PF cells. Beyond senescence barriers, lifespan-extended PF and MPF cells were eventually established and indicated spontaneous cellular immortalization. In contrast to the immortalized PF cells, immortal MPF cells showed a transformed phenotype and possessed more frequent chromosomal abnormalities and loss of p53 regulatory function. The lifespan of primary MPF and PF cells was extended by inactivation of the p53 function using transduction by SV40LT without any detectable senescent phenotype.Conclusion
These results suggest that p53 signaling might be a major determinant for the replicative senescence in the MPF cells that have the shorter lifespan and slower growth rate compared to PF cells in vitro. 相似文献75.
Jung JE Kim TK Lee JS Oh SY Kwak S Jin X Sohn JY Song MK Sohn YW Lee SY Pian X Lee JB Chung YG Choi YK You S Kim H 《Biochemical and biophysical research communications》2005,336(4):1164-1171
Genomic instability and apoptosis evasion are hallmarks of cancer, but the molecular mechanisms governing these processes remain elusive. Here, we found that survivin, a member of the apoptosis-inhibiting gene family, and aurora B kinase, a chromosomal passenger protein, were co-overexpressed in the various glioblastoma cell lines and tumors. Notably, exogenous introduction of the aurora B in human BJ cells was shown to decrease cell growth and increase the senescence-associated beta-galactosidase activity by activation of p53 tumor suppressor. However, aurora B overexpression failed to inhibit cell proliferation in BJ and U87MG cells transduced with dominant-negative p53 as well as in p53(-/-) mouse astrocytes. Aurora B was shown to increase centrosome amplification in the p53(-/-) astrocytes. Survivin was shown to induce anchorage-independent growth and inhibit anti-proliferation and drug-sensitive apoptosis caused by aurora B. Overexpression of both survivin and aurora B further accelerated the proliferation of BJ cells. Taken together, the present study indicates that survivin should accelerate tumorigenesis by inhibiting the anti-proliferative effect of p53 tumor suppressor that is activated by aurora B in normal and glioblastoma cells containing intact p53. 相似文献
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Background
The haematopoietic lineages with leukaemia lineages are considered in this paper. In particular, we mainly consider that haematopoietic lineages are tightly controlled by negative feedback inhibition of end-product. Actually, leukemia has been found 100 years ago. Up to now, the exact mechanism is still unknown, and many factors are thought to be associated with the pathogenesis of leukemia. Nevertheless, it is very necessary to continue the profound study of the pathogenesis of leukemia. Here, we propose a new mathematical model which include some negative feedback inhibition from the terminally differentiated cells of haematopoietic lineages to the haematopoietic stem cells and haematopoietic progenitor cells in order to describe the regulatory mechanisms mentioned above by a set of ordinary differential equations. Afterwards, we carried out detailed dynamical bifurcation analysis of the model, and obtained some meaningful results.Results
In this work, we mainly perform the analysis of the mathematic model by bifurcation theory and numerical simulations. We have not only incorporated some new negative feedback mechanisms to the existing model, but also constructed our own model by using the modeling method of stem cell theory with probability method. Through a series of qualitative analysis and numerical simulations, we obtain that the weak negative feedback for differentiation probability is conducive to the cure of leukemia. However, with the strengthening of negative feedback, leukemia will be more difficult to be cured, and even induce death. In contrast, strong negative feedback for differentiation rate of progenitor cells can promote healthy haematopoiesis and suppress leukaemia.Conclusions
These results demonstrate that healthy progenitor cells are bestowed a competitive advantage over leukaemia stem cells. Weak g1, g2, and h1 enable the system stays in the healthy state. However, strong h2 can promote healthy haematopoiesis and suppress leukaemia.77.
Ruiqi Zhang Yigao Feng Haifeng Li Hongxia Yuan Junli Dai Aizhong Cao Liping Xing Honglian Li 《Molecular breeding : new strategies in plant improvement》2016,36(9):122
Cereal cyst nematodes (CCN) are a global economic problem for cereal production. Heterodera filipjevi is one of the most commonly identified and widespread CCN species found in many wheat production regions of the world. Transferring novel genes for resistance to H. filipjevi from wild relatives of wheat is a promising strategy for protection of wheat crops. A set of wheat–Dasypyrum villosum chromosome addition lines, T6V#4S·6AL translocation lines and their donor parental lines were tested for their response to the nematode. D. villosum and wheat–D. villosum disomic addition line DA6V#4 were resistant. As T6V#4S·6AL translocation lines were susceptible, resistance was presumed to be located on chromosome 6V#4L. The objective of this study was to produce and characterize wheat–6V#4L translocations and confirm the chromosome location of the resistance. Introgression lines T6V#4L·6AS, T6V#4L-4BL·4BS and DT6V#4L were developed and subjected to molecular cytogenetic analysis. These and four additional wheat–6V#4 introgression lines were tested for response to H. filipjevi in the greenhouse. The results indicated that introgression lines DA6V#4, T6V#4L·6AS, T6V#4L-4BL·4BS, T6V#4L·6V#4S-7BS and DT6VL#4 had higher levels of H. filipjevi resistance than their recurrent parent. However, Del6V#4L-1 and translocation line T6V#4S·6AL were equally susceptible to wheat cv. Chinese Spring. The CCN resistance gene, temporarily named CreV, was therefore physically mapped to chromosome arm 6V#4L FL 0.80–1.00. Translocation chromosomes T6V#4L·6AS transferred to a modern wheat cv. Aikang 58 with its co-dominant molecular markers could be utilized as a novel germplasm for CCN resistance breeding in wheat. 相似文献
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He‐Lin Xu Wai‐Geng Yang Pian‐Pian Chen Rui Chen Peng‐Peng Xue Li‐Fen Wang Jian‐Dong Yuan Qing Yao Bin Chen Ying‐Zheng Zhao 《Biotechnology journal》2020,15(8)
Toad bone not only contains the rich cartilage‐like matrix but also presents low immunogenicity. It is inferred that decellularized toad bone matrix (dBECM) may provide the more profitable osteoinductive microenvironment for mesenchymal stem cells (MSCs) to promote the repair of bone defects. Herein, a hollow bone‐inspired tube is first made from hydroxyapatite (HA) and poly (γ‐glutamic acid) (PGA), and then MSCs/dBECM hydrogel is uniformly filled to its central cavity, constructing a biomimetic bone (dBECM + MSCs ? PGA + HA). In vitro scratch and transwell experiments show that dBECM hydrogel not only effectively promotes migration and proliferation of MSCs but also induces their osteogenic differentiation. Moreover, the less inflammatory macrophages infiltrate at rat skin after subcutaneously injecting dBECM hydrogel, indicating its low potential for inflammatory attack. After implanting dBECM + MSCs ? PGA + HA to critical radius defect of rabbit, X‐ray and CT imaging shows that the cortex is effectively regenerated and the medullary cavity recanalization is completed at 20 weeks. Moreover, the expression of Collagen‐II and OCN are obviously increased in the defect after implanting dBECM + MSCs ? PGA + HA. The therapeutic mechanism of dBECM + MSCs ? PGA + HA scaffold are highly associated with the enhanced angiogenesis. Collectively, the biomimetic dBECM + MSCs ? PGA + HA scaffold may be a promising strategy to improve radius defect healing efficiency. 相似文献
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Invertase plays a crucial role in carbohydrate partitioning and plant development as it catalyses the irreversible hydrolysis of sucrose into glucose and fructose. The invertase family in plants is composed of two sub-families: acid invertases, which are targeted to the cell wall and vacuole; and neutral/alkaline invertases, which function in the cytosol. In this study, 5 cell wall invertase genes (PtCWINV1-5), 3 vacuolar invertase genes (PtVINV1-3) and 16 neutral/alkaline invertase genes (PtNINV1-16) were identified in the Populus genome and found to be distributed on 14 chromosomes. A comprehensive analysis of poplar invertase genes was performed, including structures, chromosome location, phylogeny, evolutionary pattern and expression profiles. Phylogenetic analysis indicated that the two sub-families were both divided into two clades. Segmental duplication is contributed to neutral/alkaline sub-family expansion. Furthermore, the Populus invertase genes displayed differential expression in roots, stems, leaves, leaf buds and in response to salt/cold stress and pathogen infection. In addition, the analysis of enzyme activity and sugar content revealed that invertase genes play key roles in the sucrose metabolism of various tissues and organs in poplar. This work lays the foundation for future functional analysis of the invertase genes in Populus and other woody perennials. 相似文献
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Xiaolie He Li Yang Ruiqi Huang Lijuan Lin Yijue Shen Liming Cheng Lingjing Jin Shilong Wang Rongrong Zhu 《Journal of cellular physiology》2020,235(9):6032-6042
Activation of cannabinoid receptor type II (CB2R) by AM1241 has been demonstrated to protect dopaminergic neurons in Parkinson's disease (PD) animals. However, the specific mechanisms of the action of the CB2R agonist AM1241 for PD treatment have not been characterized. Wild-type (WT), CB1R knockout (CB1-KO), and CB2R knockout (CB2-KO) mice were exposed to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) for 1 week to obtain a PD mouse model. The therapeutic effects of AM1241 were evaluated in each group. Behavioral tests, analysis of neurotransmitters, and immunofluorescence results demonstrated that AM1241 ameliorated PD in WT animals and CB1-KO animals. However, AM1241 did not ameliorate PD symptoms in CB2-KO mice. RNA-seq analysis identified the lncRNA Xist as an important regulator of the protective actions of AM1241. Specifically, AM1241 allowed WT and CB1-KO animals treated with MPTP to maintain normal expression of Xist, which affected the expression of miR-133b-3p and Pitx3. In vitro, overexpression of Xist or AM1241 protected neuronal cells from death induced by 6-hydroxydopamine and increased Pitx3 expression. The CB2 receptor agonist AM1241 alleviated PD via regulation of the Xist/miR-133b-3p/Pitx3 axis, and revealed a new approach for PD treatment. 相似文献