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41.
Yang Bin Zhou Jiatao Zhao Hui Wang Anling Lei Yuanjun Xie Qiuling Xiong Sheng 《Bioprocess and biosystems engineering》2019,42(5):799-806
Bioprocess and Biosystems Engineering - Stable transfection of mammalian cells using various expression cassettes for exogenous gene expression has been well established. The impact of critical... 相似文献
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An Overview of the Biology of Reaction Wood Formation 总被引:1,自引:0,他引:1
Sheng Du Fukuju Yamamoto 《植物学报(英文版)》2007,49(2):131-143
Reaction wood possesses altered properties and performs the function of regulating a tree's form, but it is a serious defect in wood utility. Trees usually develop reaction wood in response to a gravistimulus. Reaction wood in gymnosperms is referred to as compression wood and develops on the lower side of leaning stems or branches. In arboreal, dicotyledonous angiosperms, however, it is called tension wood and is formed on the upper side of the leaning. Exploring the biology of reaction wood formation is of great value for the understanding of the wood differentiation mechanisms, cambial activity, gravitropism, and the systematics and evolution of plants. After giving an outline of the variety of wood and properties of reaction wood, this review lays emphasis on various stimuli for reaction wood induction and the extensive studies carried out so far on the roles of plant hormones in reaction wood formation. Inconsistent results have been reported for the effects of plant hormones. Both auxin and ethylene regulate the formation of compression wood in gymnosperms. However, the role of ethylene may be indirect as exogenous ethylene cannot induce compression wood formation. Tension wood formation is mainly regulated by auxin and gibberellin. Interactions among hormones and other substances may play important parts in the regulation of reaction wood formation. 相似文献
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One major challenge in the bioconversion of lignocelluloses into ethanol is to develop Saccharomyces cerevisiae strains that can utilize all available sugars in biomass hydrolysates, especially the d -xylose and l -arabinose that cannot be fermented by the S. cerevisiae strain naturally. Here, we integrated an l -arabinose utilization cassette (AUC) into the genome of an efficient d -xylose fermenting industrial diploid S. cerevisiae strain CIBTS0735 to make strain CIBTS1972. After evolving on arabinose, CIBTS1974 with excellent fermentation capacity was obtained. A comparison between genome sequences of strains CIBTS1974 and CIBTS1972 revealed that the copy number of the AUC had increased from 1 to 12. We then constructed the AUC null-mutant CIBTS1975 and gradually rescued the l -arabinose utilization defect by integrating AUC iteratively. On the other hand, the parental strain CIBTS0735 was able to acquire the same performance as CIBTS1974 by the direct introduction of 12 copies of the AUC; the performance was further improved by adding two more copies. Besides, we found that not the two transporters present in the AUC were both needed during l -arabinose utilization, GAL2 was necessary and STP2 was not essential. We have described for the first time that a high copy number of AUC is sufficient for the strain to metabolize l -arabinose efficiently independent of evolution. 相似文献
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Daniel Duran Xue Zeng Sheng Chih Jin Jungmin Choi Carol Nelson-Williams Bogdan Yatsula Jonathan Gaillard Charuta Gavankar Furey Qiongshi Lu Andrew T. Timberlake Weilai Dong Michelle A. Sorscher Erin Loring Jennifer Klein August Allocco Ava Hunt Sierra Conine Jason K. Karimy Kristopher T. Kahle 《Neuron》2019,101(3):429-443.e4
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Jinping Huang Xiao Sheng Zhangpeng Zhuo Danqing Xiao Kun Wu Gang Wan Haiyang Chen 《Cell proliferation》2022,55(1)
ObjectivesAdult stem cells uphold a delicate balance between quiescent and active states, which is crucial for tissue homeostasis. Whereas many signalling pathways that regulate epithelial stem cells have been reported, many regulators remain unidentified.Materials and MethodsFlies were used to generate tissue‐specific gene knockdown and gene knockout. qRT‐PCR was used to assess the relative mRNA levels. Immunofluorescence was used to determine protein localization and expression patterns. Clonal analyses were used to observe the phenotype. RNA‐seq was used to screen downstream mechanisms.ResultsHere, we report a member of the chloride channel family, ClC‐c, which is specifically expressed in Drosophila intestinal stem/progenitor cells and regulates intestinal stem cell (ISC) proliferation under physiological conditions and upon tissue damage. Mechanistically, we found that the ISC loss induced by the depletion of ClC‐c in intestinal stem/progenitor cells is due to inhibition of the EGFR signalling pathway.ConclusionOur findings reveal an ISC‐specific function of ClC‐c in regulating stem cell maintenance and proliferation, thereby providing new insights into the functional links among the chloride channel family, ISC proliferation and tissue homeostasis. 相似文献
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Libin Ni Jian Xiao Di Zhang Zhenxuan Shao Chongan Huang Sheng Wang Yaosen Wu Naifeng Tian Liaojun Sun Aimin Wu Yifei Zhou Xiangyang Wang Xiaolei Zhang 《Cell death & disease》2022,13(2)
The pathophysiology of spinal cord injury (SCI) involves primary injury and secondary injury. Secondary injury is a major target for SCI therapy, whereas microglia play an important role in secondary injury. The immunoresponsive gene 1 (Irg-1) has been recorded as one of the most significantly upregulated genes in SCI tissues in gene chip data; however, its role in SCI remains unclear. This study aims to illustrate the role of Irg-1 as well as its regulated metabolite itaconate in SCI. It was demonstrated that the expression of Irg-1 was increased in spinal cord tissues in mice as well as in microglia stimulated by lipopolysaccharides (LPS). It was also shown that overexpression of Irg-1 may suppress LPS-induced inflammation in microglia, while these protective effects were attenuated by Nrf2 silencing. In vivo, overexpression of Irg-1 was shown to suppress neuroinflammation and improve motor function recovery. Furthermore, treatment of microglia with itaconate demonstrated similar inflammation suppressive effects as Irg-1 overexpression in vitro and improved motor function recovery in vivo. In conclusion, the current study shows that Irg-1 and itaconate are involved in the recovery process of SCI, either Irg-1 overexpression or itaconate treatment may provide a promising strategy for the treatment of SCI.Subject terms: Apoptosis, Cell death in the nervous system, Microglia, Trauma 相似文献