Compositional Distribution of Binary Living Copolymers and Their End Sequences

ABSTRACT Transposition (the movement of discrete segments of DNA, resulting in rearrangement of genomic DNA) initiates when transposase forms a dimeric DNA-protein synaptic complex with transposon DNA end sequences. The synaptic complex is a prerequisite for catalytic reactions that occur during the transposition process. The transposase-DNA interactions involved in the synaptic complex have been of great interest. Here we undertook a study to verify the protein-DNA interactions that lead to synapsis in the Tn5 system. Specifically, we studied (i) Arg342, Glu344, and Asn348 and (ii) Ser438, Lys439, and Ser445, which, based on the previously published cocrystal structure of Tn5 transposase bound to a precleaved transposon end sequence, make cis and trans contacts with transposon end sequence DNA, respectively. By using genetic and biochemical assays, we showed that in all cases except one, each of these residues plays an important role in synaptic complex formation, as predicted by the cocrystal structure.

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Strain distribution of Si thin film grown on multicrystalline-SiGe with microscopic compositional distribution

Journal of Applied Physics ◽

10.1063/1.1520724 ◽

2002 ◽

Vol 92 (12) ◽

pp. 7098-7101 ◽

Cited By ~ 1

Author(s):

Noritaka Usami ◽

Tatsuya Takahashi ◽

Kozo Fujiwara ◽

Toru Ujihara ◽

Gen Sazaki ◽

...

Keyword(s):

Thin Film ◽

Strain Distribution ◽

Compositional Distribution ◽

Si Thin Film

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The integration preference of Sleeping Beauty at non-TA site is related to the transposon end sequences

10.21203/rs.2.19101/v1 ◽

2019 ◽

Author(s):

Yiting Zhou ◽

Guangwei Ma ◽

Jiawen Yang ◽

Yabin Guo

Keyword(s):

Site Selection ◽

Genomic Dna ◽

Consensus Sequence ◽

Mouse Cell ◽

Sleeping Beauty ◽

Consensus Sequences ◽

Target Site Selection ◽

Target Sites ◽

End Sequences ◽

Selection Of

Abstract Background: Sleeping Beauty (SB) transposon had been thought to strictly integrate into TA dinucleotides. Recently, we found that SB also integrates into non-TA sites at a lower frequency. Here we performed further study on the non-TA integration of SB. Results: 1) SB can integrate into non-TA sites in HEK293T cells as well as in mouse cell lines. 2) Both the hyperactive transposase SB100X and the traditional SB11 catalyze integrations at non-TA sites. 3) The consensus sequence of the non-TA target sites only occur at the opposite side of the sequenced junction between transposon end and the genomic sequences, indicating that the integrations at non-TA sites are mainly aberrant integrations. 4) The consensus sequence of the non-TA target sites is corresponding to the transposon end sequence. When the transposon end sequence is mutated, the consensus sequences changed too. Conclusion: The interaction between the SB transposon end and genomic DNA may be involved in the target site selection of the SB integrations at non-TA sites.

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Thermal Analysis of Butadiene Styrene Block Copolymers

Rubber Chemistry and Technology ◽

10.5254/1.3539268 ◽

1969 ◽

Vol 42 (3) ◽

pp. 918-923 ◽

Cited By ~ 2

Author(s):

J. N. Anderson ◽

F. C. Weissert ◽

C. J. Hunter

Keyword(s):

Thermal Analysis ◽

Osmium Tetroxide ◽

Polymer Degradation ◽

Glass Temperature ◽

Index Method ◽

K Value ◽

Styrene Copolymers ◽

Compositional Distribution ◽

Composition Graph ◽

Butadiene Styrene

Abstract The Gordon—Taylor—Wood relationship between composition and glass temperature has been used as the basis of a DTA method for block styrene analysis in butadiene styrene copolymers having the same microstructure and a similar compositional distribution. The determined K value of the Gordon—Taylor—Wood equation for these polymers prepared with a butyllithium catalyst is in fair agreement with values previously determined for emulsion butadiene styrene copolymers. The total styrene content of the copolymer was determined using the refractive index method, and the composition of the “non-block” segment of the copolymer was obtained from DTA measurement using a Tg as a function of composition graph The amount of block styrene can then be obtained by difference. Evidence is presented supporting the validity of the method, and the results are compared with those obtained by a chemical method which involved polymer degradation by a hydroperoxide in the presence of osmium tetroxide. The thermal analysis requires approximately one-half hour. All measurements are made on the dry polymer eliminating the necessity of redissolving the polymer as required by most other methods of analysis.

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