RNA

Part:BBa_K5223007

Designed by: Chong Yao   Group: iGEM24_SCU-China   (2024-09-30)


HQT2+4-sgRNA

HQT2+4-sgRNA is used to construct double-knockout lines for NbHQT2 (NbL10g00550.1) and NbHQT4 (NbL16g00540.1). This sgRNA is a crucial component of the CRISPR-Cas9 system, explicitly targeting the HQT2 and HQT4 genes for knockout, achieving gene-editing effects.

Biology and Usage

HQT2+4-sgRNA
Function The double-gene knockout plant of HQT2 and HQT4
Use in Nicotiana benthamiana
Backbone BGFastCas9 SS Plant
Derived from Artificial synthesis

Design and Properties:


Figure 1: Schematic Diagram of Gene Circuit

A

B

C

D

Figure 2: (A) Detection Results of HQT2 (B) Detection Results of HQT4 (C) Sequence Alignment Diagram (D) Electrophoresis Image


The results in Figure 1 demonstrate that tobacco plants successfully underwent gene knockout, achieving the expected outcomes.

Experimental Approach:

We used homologous recombination for vector construction. The gene-editing vector used was the BGFastCas9 SS Plant from BIOGROUND Biotechnology.
(1) Primer Design:
We pre-selected four target sequences corresponding to the genes (about 20 bp, complementary to the gRNA) and incorporated them into primers designed to amplify intermediate sequences from the vector.

Table 1 Primer Design

(2) Vector Construction Process (Homologous Recombination):
Component Volume
2x High-Fidelity Enzyme 25 μL
Forward Primer 2 μL
Reverse Primer 2 μL
Intermediate Vector osgRNA-U6 1 μL
ddH2O Make up to 50 μL

Table 2 PCR System

PCR cycling conditions: 98°C for 3 min; (98°C for 10 s, 50-58°C for 20 s, 72°C for 1 min) for 30 cycles; 72°C for 5 min; stored at 4°C. After PCR amplification, gel recovery was performed.
(3) Homologous Recombination:

Component Volume
5x CE Buffer II 2 μL
Exonuclease II 1 μL
Linearized Vector Fragment 150 ng
Single Target Fragment 70-80 ng
ddH2O Make up to 10 μL

Table 3

Incubate at 37°C for 30 min. The recombinant solution was stored at -20°C.
(4) Transformation and Screening:
1. Thaw competent DH5α cells on ice, add 5 µL of the recombinant product to 50 µL of thawed cells, and incubate on ice for 30 minutes.
2. Heat shock at 42°C for 60 seconds, then place on ice for 5 minutes immediately. Add 0.8 mL of LB medium to the mixture and incubate at 37°C for 1 hour with shaking.
3. Centrifuge at 6000 rpm for 3 minutes, discard approximately 700 µL of the supernatant and resuspend the cell pellet.
4. Spread the cell suspension evenly on LB agar plates containing kanamycin. After 30 minutes of incubation, invert the plates and incubate overnight at 37°C.
5. After overnight incubation, pick colonies for PCR identification of positive clones.For colonies with the correct band, send samples for sequencing. Positive clones were expanded and used for plasmid extraction.

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
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]


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Categories
//chassis/eukaryote/nbenthamiana
Parameters
None