Difference between revisions of "Part:BBa K2406079"

 
 
Line 2: Line 2:
 
__NOTOC__
 
__NOTOC__
 
<partinfo>BBa_K2406079 short</partinfo>
 
<partinfo>BBa_K2406079 short</partinfo>
 
+
==Introduction==
This part was designed to test if Lox and Rox Target sites were orthogonal. If either Cre or Dre recombinase could recognise both sites, it would catalyse recombination leading to expression of RFP. If the target sites were orthogonal, no RFP would be produced
+
This measurement construct was used to test the cross-reactivity of Lox and Rox (<partinfo>BBa_K1680005</partinfo>, <partinfo>BBa_K2406000</partinfo>). The theory behind the function of this measurement construct is summarised in the adjacent figure. Essentially, when two recombination sites cannot be recognised by a single recombinase, the terminator (represented as parallel lines in the diagram) will not be excised and there will be no RFP reporter outlook. This part is useful because it tests the cross-reactivity of the target sites in question. In order to catalyse two independent, distinct recombination events in one cell with two recombinase systems, it is vital that there is no cross-reactivity. Thus, this measurement construct tests the suitability for using Cre/LoxP and Dre/Rox in one cell.
 
+
[[File:Edinburgh UG measurement constructs.png |200px|thumb|left| Schematic outlining principle of all measurement constructs used by Edinburgh_UG 2017]]
 +
==Results==
 +
All assays performed using this measurement construct are summarised to the right. For reference, cross-reactivity and fluorescence output is compared to other measurement constructs in the context of Dre <partinfo>BBa_K2406081</partinfo> and Rox <partinfo>BBa_K2406000</partinfo>. We observed no cross-reactivity within this construct, as fluorescence output was negligible when Dre waspresent and not present. 
 +
[[File:Rox Assays.png |200px|thumb|left|All measurements performed involving Rox target sites]]
 +
[[File:Dre measurements.png|200px|thumb|left|All measurements performed involving Dre]]
 +
==Discussion==
 +
The target sites involved in this construct were previously discovered as being potentially orthogonal to other recombinases [1]. It is therefore important to test their cross-reactivity extensively to fully understand what recombinases can be used within one cell. This had not been done extensively before. Our results demonstrate no cross reactivity between the two target sites, <partinfo>BBa_K1680005</partinfo>, <partinfo>BBa_K2406000</partinfo>. This is because negligible RFP output was seen compared to control. Therefore, the Cre/LoxP and Dre/Rox can be used in an orthogonal manner within a single cell.
 +
==References==
 +
[1]Anastassiadis, K., Fu, J., Patsch, C., Hu, S., Weidlich, S., Duerschke, K., Buchholz, F., Edenhofer, F., and Stewart A.F. 2009. “Dre recombinase, like Cre, is a highly efficient site-specific recombinase in E. coli, mammalian cells and mice.” Disease Models and Mechanisms: Sep-Oct; 2(9-10):508-515.
 +
==Sequences==
 +
File below confirms sequence of all target sites, generators and measurement constructs used.
 +
[[Media:File:Sequencing Results Edinburgh UG.zip]]
 
<!-- Add more about the biology of this part here
 
<!-- Add more about the biology of this part here
 
===Usage and Biology===
 
===Usage and Biology===

Latest revision as of 11:44, 29 October 2017


Lox-Term-Rox Measurement Construct

Introduction

This measurement construct was used to test the cross-reactivity of Lox and Rox (BBa_K1680005, BBa_K2406000). The theory behind the function of this measurement construct is summarised in the adjacent figure. Essentially, when two recombination sites cannot be recognised by a single recombinase, the terminator (represented as parallel lines in the diagram) will not be excised and there will be no RFP reporter outlook. This part is useful because it tests the cross-reactivity of the target sites in question. In order to catalyse two independent, distinct recombination events in one cell with two recombinase systems, it is vital that there is no cross-reactivity. Thus, this measurement construct tests the suitability for using Cre/LoxP and Dre/Rox in one cell.

Schematic outlining principle of all measurement constructs used by Edinburgh_UG 2017

Results

All assays performed using this measurement construct are summarised to the right. For reference, cross-reactivity and fluorescence output is compared to other measurement constructs in the context of Dre BBa_K2406081 and Rox BBa_K2406000. We observed no cross-reactivity within this construct, as fluorescence output was negligible when Dre waspresent and not present.

All measurements performed involving Rox target sites
All measurements performed involving Dre

Discussion

The target sites involved in this construct were previously discovered as being potentially orthogonal to other recombinases [1]. It is therefore important to test their cross-reactivity extensively to fully understand what recombinases can be used within one cell. This had not been done extensively before. Our results demonstrate no cross reactivity between the two target sites, BBa_K1680005, BBa_K2406000. This is because negligible RFP output was seen compared to control. Therefore, the Cre/LoxP and Dre/Rox can be used in an orthogonal manner within a single cell.

References

[1]Anastassiadis, K., Fu, J., Patsch, C., Hu, S., Weidlich, S., Duerschke, K., Buchholz, F., Edenhofer, F., and Stewart A.F. 2009. “Dre recombinase, like Cre, is a highly efficient site-specific recombinase in E. coli, mammalian cells and mice.” Disease Models and Mechanisms: Sep-Oct; 2(9-10):508-515.

Sequences

File below confirms sequence of all target sites, generators and measurement constructs used. Media:File:Sequencing Results Edinburgh UG.zip Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    INCOMPATIBLE WITH RFC[25]
    Illegal AgeI site found at 886
    Illegal AgeI site found at 998
  • 1000
    COMPATIBLE WITH RFC[1000]