Difference between revisions of "Part:BBa K1997025"

 
(Functional Test)
 
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This part codes a fusion protein of sHRP-C and dCas9
 
This part codes a fusion protein of sHRP-C and dCas9
  
<!-- Add more about the biology of this part here
 
 
===Usage and Biology===
 
===Usage and Biology===
  
 +
A catalytically dead Cas9 (dCas9) formed a DNA recognition complex which can bind any sequence when co-expressed with a guide RNA. <sup>1 </sup>
 +
 +
HRP was used as a reporter,the enzymatic activity of split fragments would be reconstituted when they were reassembled. <sup>2 </sup>
 +
 +
In our project, we used engineered E.coli to produce the fusion protein of dCas9 and split-HRP fragments.
 +
 +
 +
===Sequence and Features===
 
<!-- -->
 
<!-- -->
 
<span class='h3bb'>Sequence and Features</span>
 
<span class='h3bb'>Sequence and Features</span>
 
<partinfo>BBa_K1997025 SequenceAndFeatures</partinfo>
 
<partinfo>BBa_K1997025 SequenceAndFeatures</partinfo>
  
 +
==Experimental Validation==
  
<!-- Uncomment this to enable Functional Parameter display
+
This part is validated through two ways:  PCR and functional testing
===Functional Parameters===
+
 
<partinfo>BBa_K1997025 parameters</partinfo>
+
===PCR===
<!-- -->
+
 
 +
'''Methods'''
 +
 
 +
The PCR is performed with Premix EX Taq by Takara.
 +
 
 +
F-Prime: 5’- GAATTCGCGGCCGCTTCTAGAATGC-3’
 +
 
 +
R-Prime: 5’- GGACTAGTATTATTGTTTGTCTGCC-3’
 +
 
 +
The PCR protocol is selected based on the Users Manuel.
 +
The Electrophoresis was performed on a 1% Agarose glu.
 +
The result of the agarose electrophoresis was shown on the picture below.
 +
 
 +
[[File:NUDT-025-1.jpg|300px|]]
 +
 
 +
 
 +
===Functional Test===
 +
 
 +
The plasmid was transformed into the E.coli BL21 (DE3) competent cells. After a overnight culture with (or without, as control group) 0.5mM IPTG induction, cells were collected and lysed by high pressure homogenizer. Subsequent purification was performed by nickel-nitrilotriacetic acid agarose affinity chromatography according to the standard protocol. As examined by SDS-PAGE and Western blots (probed with an anti-His-tag antibody), both of these proteins were successfully expressed and purified as a high degree of purity up to 90%.
 +
 
 +
[[File:NUDT-024-2.jpg|700px|]]
 +
 
 +
Figure 1. Prokaryotic expression and protein purification of split-HRP-dCas9 fusion proteins.
 +
 
 +
(A) Expression and purification of sHRP-C-dCas9 protein. (B) Expression and purification of sHRP-N-dCas9 protein. Western blots were probed with an anti-His-tag antibody. “-” represents the un-induced control group, “+” represents the induced group.
 +
 
 +
===References===
 +
 
 +
1. Lei S. Qi, Matthew H. Larson, Luke A. Gilbert et al. Repurposing CRISPR as an RNA-guided platform for sequence-specific control of gene expression. Cell, 2013, 152: 1173-1183.
 +
2. Kathryn E. Luker, Matthew C. P. Smith, et al. Kinetics of regulated protein–protein interactions revealed with firefly luciferase complementation imaging in cells and living animals. PNAS, 2004, 101: 12288-12293.

Latest revision as of 01:14, 21 October 2016


P+R->sHRP-C->dCas9->Ter

This part codes a fusion protein of sHRP-C and dCas9

Usage and Biology

A catalytically dead Cas9 (dCas9) formed a DNA recognition complex which can bind any sequence when co-expressed with a guide RNA. 1

HRP was used as a reporter,the enzymatic activity of split fragments would be reconstituted when they were reassembled. 2

In our project, we used engineered E.coli to produce the fusion protein of dCas9 and split-HRP fragments.


Sequence and Features

Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    INCOMPATIBLE WITH RFC[12]
    Illegal NheI site found at 1681
  • 21
    INCOMPATIBLE WITH RFC[21]
    Illegal BamHI site found at 3960
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    INCOMPATIBLE WITH RFC[1000]
    Illegal SapI.rc site found at 334

Experimental Validation

This part is validated through two ways: PCR and functional testing

PCR

Methods

The PCR is performed with Premix EX Taq by Takara.

F-Prime: 5’- GAATTCGCGGCCGCTTCTAGAATGC-3’

R-Prime: 5’- GGACTAGTATTATTGTTTGTCTGCC-3’

The PCR protocol is selected based on the Users Manuel. The Electrophoresis was performed on a 1% Agarose glu. The result of the agarose electrophoresis was shown on the picture below.

NUDT-025-1.jpg


Functional Test

The plasmid was transformed into the E.coli BL21 (DE3) competent cells. After a overnight culture with (or without, as control group) 0.5mM IPTG induction, cells were collected and lysed by high pressure homogenizer. Subsequent purification was performed by nickel-nitrilotriacetic acid agarose affinity chromatography according to the standard protocol. As examined by SDS-PAGE and Western blots (probed with an anti-His-tag antibody), both of these proteins were successfully expressed and purified as a high degree of purity up to 90%.

NUDT-024-2.jpg

Figure 1. Prokaryotic expression and protein purification of split-HRP-dCas9 fusion proteins.

(A) Expression and purification of sHRP-C-dCas9 protein. (B) Expression and purification of sHRP-N-dCas9 protein. Western blots were probed with an anti-His-tag antibody. “-” represents the un-induced control group, “+” represents the induced group.

References

1. Lei S. Qi, Matthew H. Larson, Luke A. Gilbert et al. Repurposing CRISPR as an RNA-guided platform for sequence-specific control of gene expression. Cell, 2013, 152: 1173-1183. 2. Kathryn E. Luker, Matthew C. P. Smith, et al. Kinetics of regulated protein–protein interactions revealed with firefly luciferase complementation imaging in cells and living animals. PNAS, 2004, 101: 12288-12293.