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951.
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Paul C.M. Fogg Sean Colloms Susan Rosser Marshall Stark Margaret C.M. Smith 《Journal of molecular biology》2014
Within the last 25 years, bacteriophage integrases have rapidly risen to prominence as genetic tools for a wide range of applications from basic cloning to genome engineering. Serine integrases such as that from ?C31 and its relatives have found an especially wide range of applications within diverse micro-organisms right through to multi-cellular eukaryotes. Here, we review the mechanisms of the two major families of integrases, the tyrosine and serine integrases, and the advantages and disadvantages of each type as they are applied in genome engineering and synthetic biology. In particular, we focus on the new areas of metabolic pathway construction and optimization, biocomputing, heterologous expression and multiplexed assembly techniques. Integrases are versatile and efficient tools that can be used in conjunction with the various extant molecular biology tools to streamline the synthetic biology production line. 相似文献
954.
955.
Rafael Guerrero-Preston Christina Michailidi Luigi Marchionni Curtis R Pickering Mitchell J Frederick Jeffrey N Myers Srinivasan Yegnasubramanian Tal Hadar Maartje G Noordhuis Veronika Zizkova Elana Fertig Nishant Agrawal William Westra Wayne Koch Joseph Califano Victor E Velculescu David Sidransky 《Epigenetics》2014,9(7):1031-1046
956.
Antony Kaspi Mark Ziemann Samuel T Keating Ishant Khurana Timothy Connor Briana Spolding Adrian Cooper Ross Lazarus Ken Walder Paul Zimmet Assam El-Osta 《Epigenetics》2014,9(10):1329-1338
Current computational methods used to analyze changes in DNA methylation and chromatin modification rely on sequenced genomes. Here we describe a pipeline for the detection of these changes from short-read sequence data that does not require a reference genome. Open source software packages were used for sequence assembly, alignment, and measurement of differential enrichment. The method was evaluated by comparing results with reference-based results showing a strong correlation between chromatin modification and gene expression. We then used our de novo sequence assembly to build the DNA methylation profile for the non-referenced Psammomys obesus genome. The pipeline described uses open source software for fast annotation and visualization of unreferenced genomic regions from short-read data. 相似文献
957.
958.
Trembling aspen (Populus tremuloides) is a clonal tree species, which regenerates mostly through root suckering. In spite of vegetative propagation, aspen maintains high levels of clonal diversity. We hypothesized that the maintenance of clonal diversity in this species can be facilitated by integrating different clones through natural root grafts into aspen's communal root system. To verify this hypothesis, we analyzed root systems of three pure aspen stands where clones had been delineated with the help of molecular markers. Grafting between roots was frequent regardless of their genotypes. Root system excavations revealed that many roots were still living below trees that had been dead for several years. Some of these roots had no root connections other than grafts to living ramets of different clones. The uncovered root systems did not include any unique genotypes that would not occur among stems. Nevertheless, acquiring roots of dead trees helps to maintain extensive root systems, which increases the chances of clone survival. Substantial interconnectivity within clones as well as between clones via interclonal grafts results in formation of large genetically diverse physiological units. Such a clonal structure can significantly affect interpretations of diverse ecophysiological processes in forests of trembling aspen. 相似文献
959.
Charles Q. Cai Yannick Doyon W. Michael Ainley Jeffrey C. Miller Russell C. DeKelver Erica A. Moehle Jeremy M. Rock Ya-Li Lee Robbi Garrison Lisa Schulenberg Ryan Blue Andrew Worden Lisa Baker Farhoud Faraji Lei Zhang Michael C. Holmes Edward J. Rebar Trevor N. Collingwood Beth Rubin-Wilson Philip D. Gregory Fyodor D. Urnov Joseph F. Petolino 《Plant molecular biology》2009,69(6):699-709
Targeted transgene integration in plants remains a significant technical challenge for both basic and applied research. Here
it is reported that designed zinc finger nucleases (ZFNs) can drive site-directed DNA integration into transgenic and native
gene loci. A dimer of designed 4-finger ZFNs enabled intra-chromosomal reconstitution of a disabled gfp reporter gene and site-specific transgene integration into chromosomal reporter loci following co-transformation of tobacco
cell cultures with a donor construct comprised of sequences necessary to complement a non-functional pat herbicide resistance gene. In addition, a yeast-based assay was used to identify ZFNs capable of cleaving a native endochitinase
gene. Agrobacterium delivery of a Ti plasmid harboring both the ZFNs and a donor DNA construct comprising a pat herbicide resistance gene cassette flanked by short stretches of homology to the endochitinase locus yielded up to 10% targeted,
homology-directed transgene integration precisely into the ZFN cleavage site. Given that ZFNs can be designed to recognize
a wide range of target sequences, these data point toward a novel approach for targeted gene addition, replacement and trait
stacking in plants. 相似文献
960.
We have characterised genetically and phenotypically a T-DNA insertion mutant line of A. thaliana (L.) Heynh. selected for Cs resistance when germinating and growing on Cs concentrations up to 600microM, lethal for the wild type. Measures of concentration and localisation of Cs, K, and Ca have been conducted on plants grown in vivo also utilising synchrotron light-based techniques as micro-SRXF (synchrotron radiation induced X-ray micro-fluorescence) and micro-XANES (micro X-ray absorption near edge structure) spectroscopy. We report here an attempt to apply micro-XANES to investigate Cs speciation and to measure the Cs content of living plants. The results obtained with micro-SRXF and micro-XANES spectroscopy complemented the genetic and physiological analyses: a comparison between wild type and mutant plants led to the conclusion that in our case a single gene mutation impairs Cs uptake and translocation, K and Ca homeostasis and plant biomass production. 相似文献