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鱼腥藻7120遗传转化的研究进展 总被引:1,自引:0,他引:1
鱼腥藻7120作为模式生物被广泛用于光合、固氮、进化、代谢等基本生命现象的研究。近几年, 对其基因工程的研究使人们看到它在医药、环保、能源等方面的应用潜力, 但表达效率低是其发展的瓶颈。为了提高其表达效率, 研究者从鱼腥藻7120的载体(包括启动子、复制子、选择标记基因等)的改进、目的基因的优化(密码子和SD序列)、宿主的改善、转化方法的改变等方面进行了大量探索, 除了用于功能基因的研究, 已经有几十个外源基因在鱼腥藻7120中表达。除了研究载体, 诱变鱼腥藻7120形成有利于外源基因表达的突变体和摸索转基因蓝藻最佳生长条件和表达条件, 可能是新的发展方向。 相似文献
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Andrew L. Chang Judah D. Grossman Teresa Sabol Spezio Heidi W. Weiskel Julia C. Blum Jennifer W. Burt Adrianna A. Muir Jonah Piovia-Scott Kari E. Veblen Edwin D. Grosholz 《Biological invasions》2009,11(4):773-785
The aquarium trade is an important and rapidly growing vector for introduced species in the United States. We examined this
vector by surveying pet stores in the San Francisco Bay–Delta region to compile a list of aquarium fish species commonly stocked.
We identified which of these species might be able to survive in the Bay–Delta, and investigated store representatives’ knowledge
and attitudes about biological invasions. A restrictive analysis using conservative estimates of fish temperature tolerances
and environmental conditions found that the local aquarium trade includes 5 fish species that can survive in a temperate system
such as the Bay–Delta. Under more inclusive parameters, up to 27 fish species met the criteria for survival in the Bay–Delta.
We further explored these results by comparing potential invader incidence between different types of stores. In the more
restrictive analysis, three national retail chains stocked significantly more potentially invasive species than independent
aquarium stores, but there was no difference in the more inclusive analysis. A significantly higher percentage of fish taxa
were easily identifiable and well-labeled in chain stores than in independent stores. Most aquarium store representatives
indicated willingness to take action to reduce the threat of trade-related introductions, although chain store employees were
more willing to assign responsibility for reducing this threat to the aquarium industry than were independent store employees.
Management efforts for this vector should focus on (a) improving labeling and identification of fish species in stores, (b)
expanding the often spotty data on fish physiological tolerances, especially for saltwater species, (c) educating customers
and store employees about the risks posed by pet release, and (d) providing better options for responsible disposal of unwanted
fish.
Electronic Supplementary Material
The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Gijsbers R Vets S De Rijck J Ocwieja KE Ronen K Malani N Bushman FD Debyser Z 《The Journal of biological chemistry》2011,286(48):41812-41825
LEDGF/p75 is a chromatin-interacting, cellular cofactor of HIV integrase that dictates lentiviral integration site preference. In this study we determined the role of the PWWP domain of LEDGF/p75 in tethering and targeting of the lentiviral pre-integration complex, employing potent knockdown cell lines allowing analysis in the absence of endogenous LEDGF/p75. Deletion of the PWWP domain resulted in a diffuse subnuclear distribution pattern, loss of interaction with condensed chromatin, and failure to rescue proviral integration, integration site distribution, and productive virus replication. Substitution of the PWWP domain of LEDGF/p75 with that of hepatoma-derived growth factor or HDGF-related protein-2 rescued viral replication and lentiviral integration site distribution in LEDGF/p75-depleted cells. Replacing all chromatin binding elements of LEDGF/p75 with full-length hepatoma-derived growth factor resulted in more integration in genes combined with a preference for CpG islands. In addition, we showed that any PWWP domain targets SMYD1-like sequences. Analysis of integration preferences of lentiviral vectors for epigenetic marks indicates that the PWWP domain is critical for interactions specifying the relationship of integration sites to regions enriched in specific histone post-translational modifications. 相似文献
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Philip F. Ganter William T. Starmer Marc-Andre Lachance Herman J. Phaff 《Oecologia》1986,70(3):386-392
Summary The yeast communities from slime fluxes of three deciduous trees (Prosopis juliflora, Populus fremontii and Quercus emoryi) and the necroses of two cacti (Opuntia phaeacantha and Carnegiea gigantea) were surveyed in the region of Tucson, Arizona. In addition, the yeasts carried by dipterans associated with the fluxes or necroses (Drosophila carbonaria, D. brooksae, D. nigrospiracula, D. mettleri, and Aulacigaster leucopeza) were sampled. The results indicate that each host sampled had a distinct community of yeasts associated with it. The dipterans, which can act as vectors of the yeasts, deposited yeasts from other sources in addition to those found on their associated hosts. It is argued that host plant physiology is relatively more important than the activity of the vector in determining yeast community composition. Furthermore, the average number of yeast species per flux or necrosis is not different from the average number of yeast species per fly. It is hypothesized that the vector may affect the number of species per individual flux or not, and that the number is lower than the rot or necrosis could potentially support. 相似文献
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W. Zillig Hans Peter Arnold Ingelore Holz David Prangishvili Anja Schweier Kenneth Stedman Qunxin She Hien Phan Roger Garrett Jakob K. Kristjansson 《Extremophiles : life under extreme conditions》1998,2(3):131-140
This minireview summarizes what is known about genetic elements in the archaeal crenarchaeotal genus Sulfolobus, including recent work on viruses, cryptic plasmids, a novel type of virus satellite plasmids or satellite viruses, and conjugative
plasmids (CPs), mostly from our laboratory. It does not discuss IS elements and transposons.
Received: January 22, 1998 / Accepted: February 16, 1998 相似文献
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目的:探讨降低TGFβ1的表达后,对大鼠糖尿病模型病症的改变情况,为研究TGFβ1与糖尿病发病之间提供实验数据。方法:采用腹腔注射链脲佐菌素,建立糖尿病大鼠模型,慢病毒包装TGFβ1-shRNA干扰载体,优选后皮下注射大鼠模型,以慢病毒空载shRNA注射大鼠模型作对照;检测1-5周左右两组大鼠体重和血糖变化;摘取大鼠胰腺,HE染色光学镜下观察组织形态学改变情况。结果:用RNAi沉默TGFβ1表达后,与对照组相比,干扰组大鼠体重下降较缓,血糖持续下降;HE染色可见干扰组大鼠胰岛形态较空载组稍好,分泌细胞数量稍多。结论:TGFβ1对糖尿病的发病和进展起促进作用,当抑制TGFβ1表达后,可延缓糖尿病的进展。 相似文献