Difference between revisions of "Team:Jilin China/Construction"

 
(19 intermediate revisions by 3 users not shown)
Line 66: Line 66:
 
   <table>
 
   <table>
 
   <tr>
 
   <tr>
     <td><a href="#paragraph_1" class="clickwave">Enzyme</a></td>
+
     <td><a href="#paragraph_1" class="clickwave">Golden Gate</a></td>
     <td><a href="#paragraph_2" class="clickwave">Golden Gate</a></td>
+
     <td><a href="#paragraph_2" class="clickwave">Design</a></td>
     <td><a href="#paragraph_3" class="clickwave">Intermediate</a></td>
+
     <td><a href="#paragraph_3" class="clickwave">Construction</a></td>
 
+
    <td><a href="#paragraph_4" class="clickwave">Procedure</a></td>
 
+
 
   </tr>
 
   </tr>
 
   </table>
 
   </table>
Line 80: Line 79:
 
   <!--<section class="s0"></section>-->
 
   <!--<section class="s0"></section>-->
 
   <ul class="sidenav">
 
   <ul class="sidenav">
   <li><a href="#paragraph_1">Enzyme</a></li>
+
   <li><a href="#paragraph_1">Golden Gate</a></li>
   <li><a href="#paragraph_2">Golden Gate</a></li>
+
   <li><a href="#paragraph_2">Design</a></li>
   <li><a href="#paragraph_3">Intermediate</a></li>
+
   <li><a href="#paragraph_3">Construction</a></li>
 
+
  <li><a href="#paragraph_4">Procedure</a></li>
 
   </ul>
 
   </ul>
 
   <section class="s2">
 
   <section class="s2">
Line 89: Line 88:
 
     <li class="paragraph_1 start" id="paragraph_1">
 
     <li class="paragraph_1 start" id="paragraph_1">
 
     <div>
 
     <div>
       <h2>Type IIS Restriction Endonuclease</h2>
+
       <h2>Golden Gate Assembly</h2>
<p>Restriction enzymes are traditionally classified into four types on the basis of subunit composition, cleavage position, sequence specificity and cofactor requirements<sup>[1]</sup>. Our commonly used restriction endonucleases, such as EcoRI, belong to type II restriction endonucleases, which recognize specific 4 to 8 base-pairs. The recognized sequence is inverted repeats and the cleavage site is located in the recognition site. After enzymatic cleavage and the sticky end or blunt end is produced. The cleavage diagram is as follows:</p>
+
<p>This year, we had hundreds of measurement devices to construct, which means that we need a efficient method to reduce the time and cost of construction. To address this issue, we chose the <b>Golden Gate assembly</b> , which has the advantages of short time-consuming, simple operation and high success rate<sup>[1]</sup>. </p>
 
+
<p>This assembly method is based on the <b>Type IIS restriction endonucleases</b> such as BsaI and BbsI, which differ from Type II restriction enzymes in several ways( figure 1). There are several advantages to use Type IIS restriction endonucleases.</p>
 +
<p>1. The recognition sequences of Type IIS restriction endonucleases comprise two distinct sites, one for DNA binding, the other for DNA cleavage. DNA would be cleaved at a defined distance from their non-palindromic asymmetric recognition sites, creating 4-base overhangs. Therefore, if the Type IIS recognition site is placed outside, 5' to the cleaved end, it will be lost, leading to a <b>‘scar-less’ assembly</b>. This characteristic is widely used to perform in Golden Gate assembly.</p>
 +
<p>2. Type IIS cleavage sites have no inherent sequence-specificity, so the sequence of the overhang they generate varies from one recognition site to another. Fragments produced by Type IIS-digestion of DNA molecules generally have different overhangs, therefore, and will not anneal to one another. However, if the sequences of the overhang are predetermined, by designing them into oligos, then it can be made to complement another and to be directional. Then the DNA fragments can be stitched together in the correct order and orientation in a single ligation<sup>[2]</sup>.</p>
 
<!--高能预警[Warning:Long Pieces of Codes!]-->
 
<!--高能预警[Warning:Long Pieces of Codes!]-->
  
Line 553: Line 554:
 
<!--预警结束[Warning End]-->
 
<!--预警结束[Warning End]-->
  
 +
      <p class="figure">Figure 1. The difference between the Type II restriction edonuclease and Type IIs restriction edonuclease.</p>
  
  
<p>Type IIS restriction enzymes differ from other Type II restriction enzymes in several ways.These enzymes recognize sequences comprise two distinct sites, one for DNA binding, the other for DNA cleavage. Type IIS restriction endonucleases cleave DNA at a defined distance from their non-palindromic asymmetric recognition sites, creating 4-base overhangs.</p>
 
<p>Type IIS cleavage sites have no inherent sequence-specificity, so the sequence of the overhang they generate varies from one recognition site to another. Fragments produced by Type IIS-digestion of natural DNA molecules generally have different overhangs, therefore, and will not anneal to one another. </p>
 
<p>However, if the sequence of the overhang is predetermined, by designing it into a PCR primer, for example, then it can be made to complement another and to be directional. This feature is used to great advantage in 'Golden Gate' assembly where multiple fragments can be stitched together in the correct order and orientation in a single ligation. The advantage of using Type IIS enzymes for assembly is that the recognition sequence can be placed in the primer on either side of cleavage site. If placed inside, 3' to the cleaved end, it will be retained in the construct and can be re-used subsequently. If placed outside, 5' to the cleaved end, it will be lost, leading to a ‘scar-less’ assembly. This characteristic is widely used to perform in-vitro cloning techniques such as Golden Gate cloning<sup>[2]</sup>.</p>
 
 
     </div>
 
     </div>
 
     </li>
 
     </li>
Line 564: Line 563:
 
     <li class="paragraph_2" id="paragraph_2">
 
     <li class="paragraph_2" id="paragraph_2">
 
     <div>
 
     <div>
       <h2>Golden Gate Assembly</h2>
+
       <h2>Design of the construction immediate and inserts</h2>
<p>Golden Gate Assembly is a one-tube efficient cloning method based on Type IIS restriction enzymes that cleave outside their recognition sites and leave 4-base overhangs<sup>[3]</sup>. By adding the recognition site of type IIS enzyme on the plasmid, it will be digested by enzyme and will not appear at the end constructs. The fragment gene of interest contains complementary sticky ends can ultimately be assembled by ligation<sup>[4]</sup>.</p>
+
<p>Firstly, in order to get the measurement device with suitable promoters and different RNA-based thermosensors, we designed the construction immediate (figure 2) in plasmid backbone pSB1C3, which are used to be ligated with many different gene fragments of interest. For the ‘scar-less’ assembly, we add the recognition sites of type IIS enzymes on the construction immediate, which will be digested by enzyme and will not appear at the end constructs. The gene fragments of interest contain complementary sticky ends can ultimately be assembled by simple ligation.</p>
<p>Commonly used IIS type restriction enzymes are as follows:</p>
+
<center><img src="https://static.igem.org/mediawiki/2018/f/f5/T--Jilin_China--Construction--CONSDEV.svg" width="64%" /></center>
<table width="200" border="1">
+
<p class="figure">Figure 2. The construction immediate.</p>
  <tbody>
+
<p>Secondly, our gene fragments of interest such as the DNA fragments of promoters and RNA-based thermosensors contain complementary sticky ends, whitch can ultimately be assembled into the construction immediate by simple ligation.</p>                    
    <tr>
+
      <td>Enzyme</td>
+
      <td>Recognition Sequence</td>
+
    </tr>
+
    <tr>
+
      <td>BbsI</td>
+
      <td>GAAGAC (2/6)</td>
+
    </tr>
+
    <tr>
+
      <td>BsaI</td>
+
      <td>GGTCTC (1/5)</td>
+
    </tr>
+
    <tr>
+
      <td>BtgZI</td>
+
      <td>CGTCTC (1/5)</td>
+
    </tr>
+
    <tr>
+
      <td>BsmBI</td>
+
      <td>GCGATG (10/14)</td>
+
    </tr>
+
    <tr>
+
      <td>Esp3I</td>
+
      <td>CGTCTC (1/5)</td>
+
    </tr>
+
    <tr>
+
      <td>SapI</td>
+
      <td>GCTCTTC (1/4)</td>
+
    </tr>
+
  </tbody>
+
</table>
+
<p>We chose <b>BbsI</b> and <b>BsaI</b> type IIS restriction enzymes this year.</p>
+
<p>The procedure of construction is annealed DNA oligos, phosphorylation and Golden Gate assembly:</p>
+
<h3>1. Annealed oligos</h3>
+
<p>Oligos annealing can be use to add any short stretch of DNA to a plasmid. Most of the thermosensors we designed are 40~80bp, so we can design a forward oligo with the sequence of thermosensor and with the reverse oligo being the reverse compliment so that they could anneal. We also need to make sure our annealing products contain the cohesive end bases to complement the overhangs on the plasmid. The cohesive end bases could be a part of thermosensor, because we use the Golden Gate assembly, which has no-scar products.</p>
+
                <center><img src="https://static.igem.org/mediawiki/2018/0/0a/T--Jilin_China--Construction-anneal.svg" width="70%" /></center>
+
                <p class="figure">Figure 1. Diagram of Annealed oligos</p>
+
<h3>2. Phosphorylation</h3>
+
<p>After annealing, we do the 5' phosphorylation of DNA for the subsequent ligation. Because all ligations require a 5' phosphate, which is generated through restriction dgestions or kinase treatment of fragments. Oligos ordered from a supplier would not come with a 5' phosphate unless you specify that modification is necessary. If oligos were not phosphorylated, we need to phosphorylate fragments with T4 Polynucleotide kinase prior to ligation. The T4 polynucleotide kinase can catalyze the transfer and exchange of P from the γ position of ATP to the 5'-hydroxyl terminus of polynucleotides and 3'-monophosphates.</p>
+
                <center><img src="https://static.igem.org/mediawiki/2018/c/c0/T--Jilin_China--Construction-phosphorylation.svg" width="70%" /></center>
+
                <p class="figure">Figure 2. Diagram of Phosphorylation</p>
+
<h3>3.Golden Gate assembly</h3>
+
<p>We use Type IIS restriction enzyme to digest the plasmid and use T4 DNA ligase to assemble DNA fragments we have phosphorylated before.</p>
+
                <center><img src="https://static.igem.org/mediawiki/2018/e/e7/T--Jilin_China--Construction-GG.svg" width="70%" /></center>
+
                <p class="figure">Figure 3. Diagram of Golden Gate assembly</p>
+
<p>We have recorded the detailed protocol of the Golden Gate assembly on the protocol page. Other users can refer to our protocol to design their own experiments (the amount of each added reagent in the protocol has been reduced to a minimum, it is not recommended to continue to reduce the amount. At the same time, when selecting other types of Type IIS restriction endonucleases, you should test whether the enzyme can work normally in T4 buffer. We have tested BsaI and BbsI with T4 buffer from NEB and Takara, which works well. But others hasn't been tested yet.) .</p>
+
 
</div>
 
</div>
 
</li>
 
</li>
 
<li class="paragraph_3" id="paragraph_3">
 
<li class="paragraph_3" id="paragraph_3">
 
<div>
 
<div>
<h2>Construction Intermediate</h2>
+
<h2>The workflow of the construction and selection</h2>
<p>Since we need to build more than 400 components, if we use the traditional assembly method, it will be a huge amount of work. Due to the low efficiency and success rate of traditional assembly, which will seriously delay our experimental process. We finally decide to use Golden Gate Assembly after discussion. However, the selection of the correct construct is also a problem, hence we designed the following Construction Intermediate to select the correct constructs by visible color changes of the colonies.</p>
+
<p>There are <b>stage A</b>, <b>stage B</b> and <b>stage C</b> to construct the measurement devices and selected them by the difference in color. </p>    
                <center><img src="https://static.igem.org/mediawiki/2018/6/64/T--Jilin_China--Construction-Construction_procedure.svg" width="64%" /></center>
+
<p>In stage A, the construction immediate will express chromoprotein cjBlue(BBa_K592011) in <i>E.coli</i>. We used Type IIS restriction enzyme BbsI to cut the Part I that contains the sequences of original promoter, cjBlue and double terminator (<b>figure 3, (1)</b>). Then we ligated the inserts of promoters with different expression strength on the plasmid and got the Stage B (<b>figure 3, (2)</b>).</p>
                <p class="figure">Figure 4. Diagram of Construction procedure</p>
+
<p>The Construction Intermediate includes a promoter J23104, a pigment protein tsPurple (BBa_K1033906), a pigment protein cjBlue (BBa_K592011), a BbsI site, and a BsaI site. Our Construction Intermediate has three stages of Open Reading Frame (ORF). Promoter (J23104)+cjblue in Part I can be replaced with other promoter sequences by using BbsI restriction enzymes, and the tsPurple in Part II can be replaced with RNA thermosensor sequences by using BsaI restriction endonuclease. At the first stage of OFR, the colonies are in blue due to the expression of cjBlue. After the first replacement of the promotor, the colonies in Stage B are in purple. After the second replacement, the colonies with the correct constructs show their own milky white. Color changes can refer to the following table:</p>
+
 
<div align="center">
 
<div align="center">
<img src="https://static.igem.org/mediawiki/2018/a/a3/T--Jilin_China--Construction-stage.svg"width="50%" /></center>
 
 
</div>
 
</div>
<p>We can successfully construct more than <b>200 plasmids</b> in one day. And the assembly success rate is <b>over 95%</b>, which is a very exciting result.</p>
+
<p>If the previous steps were successful conducted, the plasmid could express chromoprotein tsPurple(BBa_K1033906) rather than cjBlue in stage B. At this time, we chose the purple monocolony and extracted its plasmids. After the correct sequencing, then we conducted the next step.</p>
 +
    <p>In the next step, we used Type IIS restriction enzyme BsaI to cut the Part II that contains the sequences of RBS, tsPurple and double terminator (<b>figure 3, (3)</b>), and replaced this region with the inserts of different RNA-based thermosensors (<b>figure 3, (4)</b>).</p>
 +
    <p>If the previous steps were successful conducted, the plasmid could express superfold GFP rather than tsPurple. After the correct sequencing, we got different measurement devices. If they did not have expression intensity that is easy to detect, we would replace the promoter until the appropriate intensity was reached.</p>
 +
                <center><img src="https://static.igem.org/mediawiki/2018/6/64/T--Jilin_China--Construction-Construction_procedure.svg" width="64%" /></center>
 +
<p class="figure">Figure 3. The steps of construction of measurement devices.</p>
 
     </div>
 
     </div>
 
     </li>
 
     </li>
 
+
     <li id="paragraph_4">
     <li class="references" id="references">
+
    <div>
 +
      <h2>The procedure of Golden Gate assembly</h2>
 +
      <p>We followed three steps to assemble many measurement devices as follows:</p>
 +
      <h3>1.Annealed oligos</h3>
 +
      <p>This step could be used to add any short DNA fragment to a plasmid. Most of the thermosensors we designed are 40~80bp, so we designed top oligos with the sequences of thermosensors and with the bottom oligos, which would be the reverse compliments so that they could anneal. We made sure our annealing products contain the cohesive end bases to complement the overhangs on the construction device (Figure 4).</p>
 +
      <center><img src="https://static.igem.org/mediawiki/2018/0/0a/T--Jilin_China--Construction-anneal.svg" width="70%" /></center>
 +
                <p class="figure">Figure 4. Diagram of Annealed oligos</p>
 +
      <h3>2. Phosphorylation</h3>
 +
      <p>After annealing, the 5' phosphorylation of DNA was required for the subsequent ligation. We phosphorylated fragments with T4 Polynucleotide kinase, which could catalyze the transfer and exchange of P from the γ position of ATP to the 5'-hydroxyl terminus of polynucleotides and 3'-monophosphates (Figure 5).</p>
 +
      <center><img src="https://static.igem.org/mediawiki/2018/c/c0/T--Jilin_China--Construction-phosphorylation.svg" width="70%" /></center>
 +
                <p class="figure">Figure 5. Diagram of Phosphorylation</p>
 +
      <h3>3.Digestion and Ligation</h3>
 +
      <p>We chose Type IIS restriction enzyme to digest the plasmid and used T4 DNA ligase to assemble DNA fragments we had phosphorylated before (figure 6).</p>
 +
      <center><img src="https://static.igem.org/mediawiki/2018/e/e7/T--Jilin_China--Construction-GG.svg" width="70%" /></center>
 +
                <p class="figure">Figure 6. Diagram of Digestion and Ligation</p>    </div>
 +
    </li>
 +
    <li class="reference">
 
     <div>
 
     <div>
 
       <h2>References</h2>
 
       <h2>References</h2>
 
       <ul>
 
       <ul>
       <li id="r1">[1]NEB. Types of Restriction Endonucleases[EB/OL]. https://international.neb.com/products/restriction-endonucleases/restriction-endonucleases/types-of-restriction-endonucleases </li>
+
       <li id="r1">[1]Engler C, Kandzia R, Marillonnet S. A one pot, one step, precision cloning method with high throughput capability[J]. PloS one, 2008, 3(11): e3647.</li>
      <li>[2]NEB. Everything You Ever Wanted to Know About Type II Restriction Enzymes[EB/OL]. https://international.neb.com/tools-and-resources/feature-articles/everything-you-ever-wanted-to-know-about-type-ii-restriction-enzymes</li>
+
      <li>[2]Weber E, Gruetzner R, Werner S, et al. Assembly of designer TAL effectors by Golden Gate cloning[J]. PloS one, 2011, 6(5): e19722.</li>
      <li>[3]NEB. FAQ: Which restriction enzymes are used in Golden Gate Assembly?[EB/OL]. https://international.neb.com/faqs/2017/07/17/which-restriction-enzymes-are-used-in-golden-gate-assembly</li><li>[4]Engler C, Kandzia R, Marillonnet S. A one pot, one step, precision cloning method with high throughput capability[J]. Plos One, 2008, 3(11):e3647.</li>
+
      <li>
 
       </ul>
 
       </ul>
 
     </div>
 
     </div>

Latest revision as of 03:05, 18 October 2018

Construction

  • Golden Gate Assembly

    This year, we had hundreds of measurement devices to construct, which means that we need a efficient method to reduce the time and cost of construction. To address this issue, we chose the Golden Gate assembly , which has the advantages of short time-consuming, simple operation and high success rate[1].

    This assembly method is based on the Type IIS restriction endonucleases such as BsaI and BbsI, which differ from Type II restriction enzymes in several ways( figure 1). There are several advantages to use Type IIS restriction endonucleases.

    1. The recognition sequences of Type IIS restriction endonucleases comprise two distinct sites, one for DNA binding, the other for DNA cleavage. DNA would be cleaved at a defined distance from their non-palindromic asymmetric recognition sites, creating 4-base overhangs. Therefore, if the Type IIS recognition site is placed outside, 5' to the cleaved end, it will be lost, leading to a ‘scar-less’ assembly. This characteristic is widely used to perform in Golden Gate assembly.

    2. Type IIS cleavage sites have no inherent sequence-specificity, so the sequence of the overhang they generate varies from one recognition site to another. Fragments produced by Type IIS-digestion of DNA molecules generally have different overhangs, therefore, and will not anneal to one another. However, if the sequences of the overhang are predetermined, by designing them into oligos, then it can be made to complement another and to be directional. Then the DNA fragments can be stitched together in the correct order and orientation in a single ligation[2].

    R II

    R IIS

    R IIs

    Figure 1. The difference between the Type II restriction edonuclease and Type IIs restriction edonuclease.

  • Design of the construction immediate and inserts

    Firstly, in order to get the measurement device with suitable promoters and different RNA-based thermosensors, we designed the construction immediate (figure 2) in plasmid backbone pSB1C3, which are used to be ligated with many different gene fragments of interest. For the ‘scar-less’ assembly, we add the recognition sites of type IIS enzymes on the construction immediate, which will be digested by enzyme and will not appear at the end constructs. The gene fragments of interest contain complementary sticky ends can ultimately be assembled by simple ligation.

    Figure 2. The construction immediate.

    Secondly, our gene fragments of interest such as the DNA fragments of promoters and RNA-based thermosensors contain complementary sticky ends, whitch can ultimately be assembled into the construction immediate by simple ligation.

  • The workflow of the construction and selection

    There are stage A, stage B and stage C to construct the measurement devices and selected them by the difference in color.

    In stage A, the construction immediate will express chromoprotein cjBlue(BBa_K592011) in E.coli. We used Type IIS restriction enzyme BbsI to cut the Part I that contains the sequences of original promoter, cjBlue and double terminator (figure 3, (1)). Then we ligated the inserts of promoters with different expression strength on the plasmid and got the Stage B (figure 3, (2)).

    If the previous steps were successful conducted, the plasmid could express chromoprotein tsPurple(BBa_K1033906) rather than cjBlue in stage B. At this time, we chose the purple monocolony and extracted its plasmids. After the correct sequencing, then we conducted the next step.

    In the next step, we used Type IIS restriction enzyme BsaI to cut the Part II that contains the sequences of RBS, tsPurple and double terminator (figure 3, (3)), and replaced this region with the inserts of different RNA-based thermosensors (figure 3, (4)).

    If the previous steps were successful conducted, the plasmid could express superfold GFP rather than tsPurple. After the correct sequencing, we got different measurement devices. If they did not have expression intensity that is easy to detect, we would replace the promoter until the appropriate intensity was reached.

    Figure 3. The steps of construction of measurement devices.

  • The procedure of Golden Gate assembly

    We followed three steps to assemble many measurement devices as follows:

    1.Annealed oligos

    This step could be used to add any short DNA fragment to a plasmid. Most of the thermosensors we designed are 40~80bp, so we designed top oligos with the sequences of thermosensors and with the bottom oligos, which would be the reverse compliments so that they could anneal. We made sure our annealing products contain the cohesive end bases to complement the overhangs on the construction device (Figure 4).

    Figure 4. Diagram of Annealed oligos

    2. Phosphorylation

    After annealing, the 5' phosphorylation of DNA was required for the subsequent ligation. We phosphorylated fragments with T4 Polynucleotide kinase, which could catalyze the transfer and exchange of P from the γ position of ATP to the 5'-hydroxyl terminus of polynucleotides and 3'-monophosphates (Figure 5).

    Figure 5. Diagram of Phosphorylation

    3.Digestion and Ligation

    We chose Type IIS restriction enzyme to digest the plasmid and used T4 DNA ligase to assemble DNA fragments we had phosphorylated before (figure 6).

    Figure 6. Diagram of Digestion and Ligation

  • References

    • [1]Engler C, Kandzia R, Marillonnet S. A one pot, one step, precision cloning method with high throughput capability[J]. PloS one, 2008, 3(11): e3647.
    • [2]Weber E, Gruetzner R, Werner S, et al. Assembly of designer TAL effectors by Golden Gate cloning[J]. PloS one, 2011, 6(5): e19722.